Materials Chain News
The Materials Chain is a proactive research network aspiring to share and communicate its scientific work not only amongst its members but with the international materials science community.
Scroll through our news archive to learn more about recent Materials Chain activities.
News Archive
- Three questions for Prof. Dr Christof Schulz
21st September 2023,
HY Summit im Ruhrgebiet. Read original article
© UDE/Frank PreußThe HY Summit brings together the "who's who" from science, politics and business in the hydrogen sector. A very central question at the Hydrogen Summit: How can the hydrogen ramp-up succeed? Materials Chain member Prof. Dr. Christof Schulz explains which technologies science is developing for industrial scale and how this will make hydrogen production independent of expensive precious metals.
The Ruhr region is considered a hydrogen stronghold. What makes the region so interesting and which scientific institutions and cooperations enable excellent hydrogen research?
The Ruhr region understands, can and needs hydrogen. The understanding is continuously developed by a research landscape with a density of universities, Max Planck Institutes and technology-related research institutions that is unique in Europe. The ability results from the interdisciplinary cooperation of the research partners, who quickly implement fundamental findings technologically, often in cooperation with the numerous industrial partners in the region. And this is true both on the side of the production and use of hydrogen and on the side of the development and production of the next generations of the facilities and technologies required for this. The need is obvious for a metropolitan region with energy-intensive industry and 5 million residents, many of whom worry that "business as usual" cannot work.
For the whole interview follow the link below. - Doris Segets researches materials for renewable energies
18th September 2023,
Advancing key technology. Read original article
© UDE/Fabian StrauchTiny nanoparticles promise one thing above all: to make the energy transition possible. To speed up the development of the particles, Materials Chain member Prof. Dr Doris Segets wants to use artificial intelligence. In an interview, the scientist explains how she wants to make the nanomaterials, which work wonderfully in the laboratory environment, usable for industry - for example, for the ramp-up of hydrogen.
Professor Segets, you are a chemical engineer and therefore an expert in a discipline that is considered a key technology for the energy transition. What exactly are you researching?
I work with nanoparticles. That means I focus on the production and processing of materials. Processing means that we not only build the particles according to their necessary properties, but also develop them further. We turn particles into superparticles and ultimately into structured layers, such as electrodes. These are needed for hydrogen electrolysis, for example. So far, the catalysts in electrodes that get hydrogen production going are made of precious metals. These are expensive and difficult to obtain. That's why we're developing precious metal-free catalysts at the UDE. Incidentally, there is a similar resource problem with wind energy, because permanent magnets based on rare earths are installed in the rotors. For this, too, we need cheap and easily available new materials.
To the whole interview (english version): https://www.uni-due.de/2023-09-14-materials-doris-segets
https://www.uni-due.de/2023-09-11-materialien-fuer-die-energiewende
- Making electrodes robust for H2 production
18th September 2023,
Why I do research: Vineetha Vinayakumar. Read original article
© UDE/Melanie Daamen‘We live in a world where energy demand is rising day by day’, says Dr Vineetha Vinayakumar. That’s why the materials scientist focuses on developing efficient and environment-friendly ways to produce hydrogen.
You are an expert on Materials Engineering. Can you explain your current research focus?
Currently, I focus on Green Hydrogen whose climate impact is negligible. One production method is the electrochemical splitting of water molecules into hydrogen and oxygen. Here, my research focuses mainly on the anode developments for alkaline electrolysis. As part of a hydrogen flagship project (H2Giga), I investigate electrodes composed of metal oxides at different stages of processing employing a coherent workflow to optimize each step individually thereby making these electrodes more efficient, stable and scalable. I apply my knowledge and experience in in-depth material characterization and processing using a set of complementary advanced techniques to investigate these electrode materials in their powder, suspension, and thin film form and use the information to further optimize them.
To the whole article (english version): https://www.uni-due.de/2023-09-14-materials-vineetha-vinayakumar
https://www.uni-due.de/2023-09-14-materials-vineetha-vinayakumar
- Catalysts on textiles
7th September 2023,
Federal Ministry for Climate Action promotes UDE project. Read original article
© UDE/Frank Preuß (l.), privat (r.)Hardly anything works in the chemical industry without catalysts. The UDE Faculty of Chemistry and the German Textile Research Center North-West (DTNW) are investigating how their use could be optimized in the "OrgKatTex" project. The German Federal Ministry for Economic Affairs and Climate Action is funding the project with 501,000 euros; the UDE is receiving 229,000 euros of this.
Catalysts are used in about 90 percent of all chemical processes today to accelerate reactions or make them possible at all. These reactions are often carried out in a liquid, such as an organic solvent. In university research, catalysts are usually used that are dissolved in the solvent (homogeneous catalysis). Companies, on the other hand, prefer catalysts fixed to surfaces (heterogeneous catalysis), which do not have to be separated from the product at great expense after the reaction.
https://www.uni-due.de/cenide/en/news-detail.php?id=catalysts-on-textiles
- Materials Science Meets Artificial Intelligence – Advancements in Research and Innovation
31st August 2023,
MCIC 2023: International Conference, Register Now. Read original articleThe 2023 Materials Chain International Conference: Materials Science Meets Artificial Intelligence – Advancements in Research and Innovation (MCIC 2023) brings together scientists from experiments and simulations as well as industry. We will discuss current developments and open questions in data-driven materials science from atomistic to microstructure descriptions and structure-property relationships as well as in research data management. Register now.
MCIC 2023 is now open for registration.https://materials-chain.com/news-events/conferences/mcic-2023/
- Material Design with the Help of Artificial Intelligence
29th August 2023,
MPIE develops a new machine learning model. Read original article
© Compiled from Adobe Stock ImagesScientists at the Max-Planck-Institut für Eisenforschung are developing a new machine learning model for corrosion-resistant alloys and publish their results in the journal Science Advances.
2.5 trillion U.S. dollars annually - that's the amount of economic damage caused by corrosion worldwide. Science and industry have ever since been searching for new alloys that are resistant to corrosion and for coatings that protect alloys from corrosion. In the search, artificial intelligence (AI) is increasingly being applied to predict the corrosion behavior of materials to find optimal alloy compositions. However, the predictive power of previous AI models is limited because not all relevant data can be considered. Scientists at the Max-Planck-Institut für Eisenforschung (MPIE) in Düsseldorf, Germany, have developed a new machine learning model that can predict corrosive failure 15% more accurately than previous models and suggest new resistant alloys. Originally developed for the critical area of pitting corrosion in high-strength alloys, the model can be extended to all alloy properties. The researchers published their findings in the journal Science Advances.
To read the whole article (German) follow the link below:
https://nachrichten.idw-online.de/2023/08/29/materialdesign-mit-hilfe-kuenstlicher-intelligenz
- How do flame retardants affect textiles?
22nd August 2023,
New DFG project. Read original article
© Wael Ali (DTNW)When there's a fire, it quickly spreads to curtains or upholstered furniture. Flame retardants are supposed to prevent this - but many of them are toxic to humans and the environment. In order to be able to produce safer flame retardants in the future, CENIDE member Prof. Dr. Burak Atakan from the Chair of Thermodynamics at UDE is investigating their mode of action together with the German Textile Research Center North-West (DTNW), an affiliated institute of UDE. The German Research Foundation (DFG) will fund the project for the next three years with approximately 612,000 euros.
Flame retardants are used to prevent or delay the spread of fire through highly flammable textiles. However, many of these are harmful to the environment and pose a health hazard. Environmentally compatible alternatives are still being sought. "To do this, we first need to better understand the mechanism of action of flame retardants. So far, however, there has been a lack of simplifying experiments that allow the different steps to be studied separately," explains Prof. Burak Atakan.
https://www.uni-due.de/2023-08-17-dfg-projekt-zu-flammschutzmittel
- Kevinjeorjios Pellumbi optimizes chemical reactions
22nd August 2023,
Why I do research. Read original article
© RUB/Marquard"I want my research to have impact," says PhD student Kevinjeorjios Pellumbi. That's why he prefers to work on topics that help answer the pressing questions of our time. And he does so with great enthusiasm.
Mr. Pellumbi, what do you find most fascinating about materials science?
The most fascinating thing is that you can develop solutions for the pressing questions of our time. I want my research to have an impact, I want to make a difference. For example, by developing a material that is needed to establish a coupling of renewable energies with chemical production. As a materials scientist, I can create tailored solutions to specific problems. But I can also work on completely new things that no one needs today - but that could be helpful for everyone in ten years. One example is lithium-ion batteries for energy storage, which started on a lab scale and are now a household item. The time we spent scaling up the technology felt very short to me.
To the whole interview (english version): https://www.uni-due.de/cenide/en/news-detail.php?id=kevinjeorjios-pellumbi-optimizes-chemical-reactions
https://www.uni-due.de/2023-08-17-Kevinjeorjios-Pellumbi-Materialwissenschaft
- Nanomagnetism at a glance
16th August 2023,
New at UDE: Sabrina Disch. Read original article
© UDE/Bettina Engel-AlbustinMagnetism is in computers, wind turbines, medical devices or other machines that run on motors. How magnetism works on the nanoscale is analyzed by Dr. Sabrina Disch. She is a new professor of inorganic chemistry at the UDE Faculty of Chemistry.
Magnetism in materials is often affected by the smallest structures: nanostructures are on the order of a millionth of a meter. Magnetic nanoparticles produced in the laboratory are good models for nanoscale defects or interfaces, but they also have direct applications, for example in cancer treatment, medical imaging, drug carriers or as catalyst materials. "Understanding magnetism at the nanoscale as well as in higher-level structures is a prerequisite for producing materials with tailored magnetic properties for these highly relevant areas of application for society," says Professor Disch.
After studying chemistry at the University of Cologne, Sabrina Disch conducted research at the Jülich Research Center and received her doctorate with honors from RWTH Aachen University in 2010. This was followed by several years abroad: first as a postdoc at the University of Oregon (USA) and the Université Libre de Bruxelles (Belgium). Then she was a Marie Curie Fellow at the Institut Laue-Langevin, an international research center in Grenoble, France. Back in Germany, she established an independent research group at the University of Cologne starting in 2014, initially funded as the Liebig Group, and from 2015 as the Emmy Noether Group. Disch's research has received several awards, most recently the Wolfram Prandl Prize in 2020 for her neutron research.
https://www.uni-due.de/2023-08-15-nomagnetismus-sabrina-disch
- Developing energy storage systems of the future
20th July 2023,
SPP individual projects on Carnot batteries approved. Read original article
© Burak AtakanSustainable sources provide energy when the natural conditions are right - for example, solar radiation, tides or wind. Supply and demand do not always match, but efficient technologies to store energy on the order of gigawatt hours are still lacking. Carnot batteries offer a possible solution. In April 2022, a corresponding priority program was established, coordinated by UDE. Recently, the German Research Foundation (DFG) approved 17 individual projects with a total funding amount of about 6.5 million euros.
In Priority Program 2403 "Carnot Batteries: Inverse Design from Market to Molecule," scientists are approaching the optimal battery from an unusual angle: using a "top-down methodology," the goal is to develop what is needed - not what is considered feasible with current resources. "Economics provides the necessary targets for future energy markets, on which we then base scientific and technical research," says Materials Chain member Prof. Dr. Burak Atakan, explaining the concept. The head of the "Thermodynamics" department at the UDE Institute for Energy and Material Processes is the coordinator of SPP 2403. Of the 17 individual projects at 15 locations*, two are located at the UDE: Atakan's working group is dedicated to the working fluid of the batteries, which will mainly consist of hydrocarbons. In the coming years, the team wants to find out which mixtures are needed beyond that, and in what composition, to achieve the best possible result. "We are investigating very many parameters: Temperature, pressure or mixture composition are just a few of them - this is a big challenge not only in our subproject," says Atakan.
https://www.uni-due.de/2023-07-10-dfg-bewilligt-projekte-zu-carnot-batterien
- UDE Research Magazine: Materials Chain members Nils Weimann and Harry Hoster in Latest Issue
19th July 2023,
. Read original article
© Bettina Engel-AlbustinIn its latest issue, the research magazine of the University of Duisburg-Essen (UDE) presents articles about the research of Materials Chain members Prof. Dr. Nils Weimann and Prof. Dr. Harry Hoster. The articles in the UDE Research Magazine illustrate the commitment and role they play in researching and developing future-oriented technologies.
The article on Nils Weimann, Professor of Semiconductor Technology at the Faculty of Engineering and Head of the High Frequency Devices Group, is devoted to the establishment of the Terahertz Integration Center, which is unique in Germany. The applications of terahertz (THz) waves are many, from detecting skin cancer to determining the water content of a plant. The new center, supported by more than seven million euros in state and EU funding, will enable researchers to cover the entire technology chain, from the production of the semiconductor material to the fabrication of the chips and the development of specialized THz measurement technology.
The article about Harry Hoster, head of the Chair of Energy Technology and scientific director of the ZBT, is dedicated to the topic of hydrogen, which plays an important role in the current century. As a high school student, Hoster was already fascinated by hydrogen as an alternative energy source and has been working continuously on this topic ever since. Hoster has published widely on the subject and shared his expertise at international conferences. As the new scientific director of ZBT, he continues his research and contributes to the development of innovative energy conversion and storage technologies.
The full articles on Nils Weimann and Harry Hoster can be found in the current research magazine of the University of Duisburg-Essen.https://forschungsmagazin.online/de/endlich-passt-alles-zusammen/
- Chemist seeks talent
19th July 2023,
2nd Henriette Heart Scout at the UDE. Read original article
© UDE/Frank PreußThey are molecules that are not directly - but nevertheless inseparably - connected: Interlocked molecules behave like chain links or a ring on a rod closed on both sides. Materials Chain member Prof. Dr. Jochen Niemeyer is researching how they are applied at the Faculty of Chemistry at the University Duisburg-Essen (UDE). As a scout in the Alexander von Humboldt Foundation's Henriette Herz Program, he is now looking for international scientific support.
The Henriette Herz Scouting Program enables outstanding researchers like Professor Niemeyer to select three international scientists for a Humboldt Fellowship at UDE. Young talents as well as experienced researchers are eligible. The sponsorship period is 24 months for postdocs and 18 months for experienced researchers. In February, Mathematics Professor Irwin Yousept was named the 1st Henriette Heart Scout at UDE (www.uni-due.de/2023-02-16-erster-henriette-herz-scout-der-ude/). The Humboldt Foundation program is funded by the German Federal Ministry of Education and Research.
The research of the Niemeyer group at UDE is part of Organic and Supramolecular Chemistry with a special focus on interlocked molecules. As catalysts, these accelerate chemical reactions while avoiding unwanted by-products.
When selecting the Henriette Herz fellows, Professor Niemeyer believes it is important to have a diverse approach: "Ideally, one of the three people will already be permanently employed at another institution - in industry, for example. In this case, we want to use the funding to highlight the opportunity to enter a scientific career after all," says the UDE researcher. The second talent he is looking for is in Japan. "There are many excellently qualified chemists there, but they are often not drawn to Europe. I want to use my contacts from my research stay in Japan to select fellows." The third decision will be made by Jochen Niemeyer via an anonymous process. "We are launching an ideas competition on a specific question, for which interested researchers can send us a short proposal. In this way, we deliberately focus on the quality of the proposal and look less at the CV."
https://www.uni-due.de/2023-07-13-zweiter-henriette-herz-scout-sucht-talente
- Publication by Materials Chain members
18th July 2023,
New quantum paths for coherent phonons. Read original article
(c) Mayer/CENIDEResearchers at the Max Born Institute in Berlin and the University of Duisburg-Essen have developed a concept for excitation and sensing of coherent phonons in crystals with temporarily broken symmetry. This groundbreaking research has now been published in the prestigious journal Physical Review B. Materials Chain members Prof. Dr. Michael Horn-von Hoegen and Prof. Dr. Klaus Sokolowski-Tinten are also involved in the publication.
The research team presents a novel method for manipulation via the reduction of crystal symmetry by suitable optical excitation, as demonstrated here for the prototypical crystalline semimetal bismuth (Bi). This research demonstrates that the targeted optical induction of symmetry breaking leads to the ability to change the excitation spectrum of a crystal on ultrashort time scales. These findings open promising avenues for transient control of material properties, laying the foundation for innovative applications in optoacoustics and optical switching.
https://www.uni-due.de/cenide/en/news-detail.php?id=publication-by-cenide-members
- Hydrogen hotspot
4th July 2023,
Duisburg. Read original article
© Duisburg ist echt/ Duisburg KontorGermany is to become a hydrogen republic - and the hydrogen and fuel cell center ZBT Gmbh (ZBT) is a linchpin in this. It is not only the economy on the Rhine and Ruhr that benefits.
The innovative research at the ZBT is internationally renowned. Consequently, in the fall of 2021, the German Federal Ministry of Transport selected the university's affiliated institute as one of only four locations nationwide for a national hydrogen center. The TrHy is to receive 60 million euros in federal funding, with the state providing another 50 million euros. By 2025, Duisburg will be a hotspot for the hydrogen industry, with the participation of renowned industrial partners such as Rheinmetall and HKM as well as RWTH Aachen University and the Jülich Research Center. Thus, the Whois Who of hydrogen research and industry will meet in Duisburg in the future. New companies are likely to settle here, and jobs will be created.
Unique test areas
The test field in front of the building is unique in Europe; here, all the technical processes and operations that will occur at hydrogen filling stations in the future can be analyzed and controlled - safety is the priority. Here, for example, dispensers for hydrogen can be tested for their practicality. Different storage tanks operate at different pressures. Up to now, cars can be refueled quickly with the maximum of 900 bar, while the pressure for filling trucks is still less than half that. In the future, the technology is to be improved so that trucks and buses can be supplied with large quantities in a short time.
Work is also to be done on establishing rules and standards for hydrogen in the hall on the HKM site. Training and continuing education are another building block in the concept. After all, the energy carrier has not played a major role so far among many occupational groups that will be dealing with hydrogen in the future. The new hydrogen education center is planned as a joint project right next to TrHy. Partners are ZBT, Kraftwerksschule Essen (KWS), the city and the Port of Duisburg.
https://www.uni-due.de/2023-06-26-wasserstoff-hotspot-duisburg
- Interdisciplinary view of phase transitions
4th July 2023,
Better understanding of material properties. Read original article
© UDE/Melanie DaamenWhen the Titanic collided with the iceberg, it broke apart. One of several reasons for the catastrophe: the steel used was extremely brittle. So-called phase transitions in the solid state explain this brittleness of metals. Triggered by temperature changes, material properties can change, as in the collision with the iceberg. Today, a different steel would be used, because science knows more about these phase transitions. Experts from materials science, physics and engineering are conducting research on them. Under the leadership of University of Duisburg-Essen (UDE) Prof. Gabi Schierning, an article has now appeared in Advanced Energy Materials* that takes an interdisciplinary look at the field and sets out future research goals.
In everyday life, we encounter phase transitions as changes in the state of aggregation, for example from liquid water to water vapor. In a phase transition in a solid, on the other hand, the state of aggregation remains the same. "However, the properties of the solid change, for example due to pressure or temperature changes. A solid can become very brittle or magnetic above a certain temperature by changing its crystal structure," says materials scientist Gabi Schierning.
Materials Chain member Prof. Anna Grünebohm from Ruhr University Bochum (RUB) explains a very concrete application example for the mechanism of the phase transition: "A change in shape during the phase transition can be used specifically in medical technology when using stents. Once inserted in the patient:s body, the medical implants can change their shape due to a temperature pulse and expand in the calcified bloodstream."
Phase transitions are being studied from different angles in various scientific disciplines.
- Tetris for Industry
14th June 2023,
. Read original article
© UDE/CENIDE - eventfotograf.inIt stands like a stacking game in the labs of the NanoEnergieTechnikZentrum (NETZ) – a modular roll-to-roll coater whose individual blocks can be assembled in different ways as required. Typically, such a pilot plant is used by technically oriented institutes or on the spot for preliminary tests in industrial enterprises. At universities, the full-scale plant is a rarity.
Every block stands for a different process in the chain, such as different application or drying processes. The coating system belongs to the research group of Materials Chain member Dr. Doris Segets, professor for the process engineering of electrochemical functional materials and holder of the newly established Chair in Particle Science and Technology. Basically, her team – pictured, Adil Amin and Dr. Fatih Özcan – is working to make scientific developments usable in practice. The researchers are focusing particularly on energy applications and sustainable technologies, including batteries, fuel cells, electrolysers, and electrosynthesis.
What that means in more detailed terms is: How is it possible to transfer new materials that function outstandingly well in the lab to industrial applications? We still lack suitable technologies and scaling methods for new materials, because what works on a laboratory scale often looks quite different on an industrial scale – and is too expensive.
‘Trial and error won’t get you any further here,’ explains Segets. ‘You have to understand the fundamental processes and mechanisms.’ Her team is therefore analysing the properties of particles, for example to understand how they behave in contact with selected liquids. If the particles can be evenly distributed, the result is an ink that can be used to easily print structured, functional layers for numerous applications – initially on the coating system at NETZ.
- Why so charged?
13th June 2023,
Contact electrification project. Read original article
Picture: Prof. Hermann Nienhaus (l.) and Prof. Rolf Möller (r.) in front of the experimental apparatus with an electronic charge amplifier.If two materials come into contact, an electrostatic charge transfer can occur. It may cause small sparks during discharging. Everyone has experienced this phenomenon when, e.g., touching a door handle. Such contact triboelectricity can unintentionally trigger sparks and explosions in dusts and granulates, but it can also be used to generate electricity with sports textiles, for example. Surprisingly, the basic mechanisms behind the phenomenon are still unresolved. Research in an experimental physics group at UDE contributes to the understanding of the effects. A project on charge transfer is now being funded by the German Research Foundation (DFG) with over 250,000 euros for three years.
Microscopic contact between materials often leads to charging. If there are many contacts, very high voltages of several kilovolts can be generated. "Although this has been known for a long time, it is still unclear what kind of charged particles are transferred during contact. They could be individual electrons, atoms (ions) or entire molecules consisting of several atoms", explains Prof. Dr. Rolf Möller, who is leading the project together with his colleague Matierals Chain member Prof. Dr. Hermann Nienhaus.
To get a better understanding one would have to analyze the exact moment when the charge is transferred from one material to the other. "This happens rather fast, namely in a few millionths of a second or even faster", says Prof. Nienhaus. The process cannot be detected with conventional devices. That's why the research group has developed new electronic amplifiers that measure very small charges in microseconds.
Thanks to this technique, it is now possible to observe the contact electrification of a sphere with high temporal and charge resolution: a sphere with a diameter of one millimeter is dropped freely onto a plate on that it bounces several times. The research group is experimenting with different sphere and plate materials including metals and insulators and changing the surrounding atmosphere. "Our experiment is being conducted with very high precision and a charge and time resolution that has never been seen before", Möller emphasizes. "Our goal is to fundamentally understand the physical mechanisms of charge transfer. Eventually, this would allow contact charges to be avoided, controlled or even externally adjusted in the near future."
https://www.uni-due.de/2023-05-31-recharge-charge-transfer-ude
- Awarded: Kai S. Exner receives the Nernst-Haber-Bodenstein Prize 2023
9th June 2023,
. Read original article
© Maksim SokolovThe German Bunsen Society for Physical Chemistry awarded the prestigious Nernst-Haber-Bodenstein Prize for the year 2023 to Materials Chain member Prof. Dr. Kai S. Exner on June 05. The prize recognizes his outstanding scientific achievements in the theoretical description of electrocatalytic processes at electrified solid/liquid interfaces, in particular his contributions to the understanding of trends using volcano analysis.
The Nernst-Haber-Bodenstein Prize is awarded annually to young scientists up to the age of 40 in recognition of outstanding scientific achievements in physical chemistry in memory of Max Bodenstein, Fritz Haber and Walther Nernst.
Prof. Exner's work makes important contributions to the identification of active sites as well as the reaction mechanisms running over them for electrochemical reactions in the context of a sustainable energy economy. His recent contributions address selectivity trends as well as stability trends for electrocatalytic processes using theoretical methods in addition to the study of activity trends.
- 10. NRW Nano Conference
6th June 2023,
Best Poster Awards for CENIDE PhD Candidates. Read original article
The NRW Nano Conference, highlighting NRW's leading role in the field of nanotechnology and materials science, took place from May 23 - 24. The conference covers a wide range of topics and offers insights into future trends and the latest developments in nanotechnology. A special highlight of the event was the presentation of scientific papers by young academics on more than 100 posters. This poster exhibition provided a comprehensive overview of groundbreaking developments and innovations. As part of the "Young Academics Award", prizes were awarded to the three best poster presentations. Two CENIDE PhD Candidates also received awards.
Best Poster Award 1st Place: Tamara E. Czerny – ElectroEnergetic Functional Materials (EEFM) (University of Duisburg-Essen, Faculty of Engineering) Jun.-Prof. Franziska Muckel
Best Poster Award 3rd Place: Fabian Nocke – Institute of Physiology (University of Duisburg-Essen, Faculty of Medicine) – Jun.-Prof. Katja Ferenz
The NRW Nano Conference offers a platform for companies and institutes to present their research, products and services in the context of an accompanying exhibition. The exchange will attempt to develop joint strategies to make NRW more competitive as a future business location with the latest research, products, ideas and business models.
https://www.uni-due.de/cenide/en/news-detail.php?id=best-poster-awards-for-cenide-phd-candidates
- Junge Akademie and Carl Hanser Verlag publish children's book "Young Scientists"
30th May 2023,
Materials Chain member portrayed in book. Read original article
(c) CENIDEThe Junge Akademie has published the children's book "Young Scientists" in collaboration with the renowned Carl Hanser Verlag. The book will be available in stores from May 15, 2023. It is aimed at children and young people from the age of twelve and aims to awaken interest in science, to show personal life paths in science and to inspire young readers to embark on their own journeys of discovery. Materials Chain member Prof. Dr. Doris Segets is one of the researchers portrayed in this inspiring book.
In "Young Scientists", thirty researchers from different disciplines report on their first encounters and formative experiences in science. Readers learn about the paths and sometimes detours that can lead to a scientific career and the fascinating questions that can be explored in research. Inspiring life paths are presented, such as that of an outsider in kindergarten who eventually becomes a professor of computer science. Also featured are the daughter of an illiterate woman who devotes herself to Islamic theology and a legal scholar who wants to understand the importance of rules in our coexistence. These and thirty other stories of humanities, social, natural and engineering scientists are intended to inspire and generate interest in science. Most of those portrayed are, like Doris Segets, active or former members of the Junge Akademie and thus also reflect its diversity.
- Materials Chain members at Pint of Science in Duisburg
19th May 2023,
For the first time in Duisburg!. Read original article
Launched in 2013 in the UK, the Pint of Science Festival will take place in over 400 cities worldwide from May 22-24, 2023. For the first time, the festival is also coming to Duisburg and Mateirals Chain is right in the middle of it. Three Matierials Chain members - Harry Hoster, Doris Segets and Axel Lorke - will be at the festival, which will take place in the legendary student pub Finkenkrug on Sternbuschweg.
On the second day of the festival, Wednesday, May 24, starting at 7 p.m., Harry Hoster, scientific managing director of the Center for Fuel Cell Technology (ZBT) GmbH and professor of energy technology at the University of Duisburg-Essen, will give a lecture on green hydrogen. Also on board: lobsters, dinosaurs and Mark Twain - we can be curious. Doris Segets, normally holder of the Chair of Particle Physics and Technology at the University of Duisburg-Essen, will unravel the mystery of how and why particles get into electrodes and what hydrogen has to do with it. And if you're still in the mood for more, Axel Lorke, head of the Experimental Physics Research Group at the Faculty of Physics, will explain why everything is quantum mechanics and that the quantum is our friend.
Tickets are available for 2.50 euros on the Pint of Science Germany e.V. website.
https://www.uni-due.de/cenide/en/news-detail.php?id=cenide-members-at-pint-of-science-in-duisburg
- Innovative research in elevator pitch videos
19th May 2023,
Jil-Lorean Gieser and Varatharaja Nallathambi in brief portrait. Read original article
(c) CENIDETwo exciting Elevator Pitch videos showcasing the research of PhD students Jil-Lorean Gieser and Varatharaja Nallathambi from the group of Materials Chain member Stephan Barcikowski are now online. The videos were created in an Elevator Pitch workshop led by postdoc Dr. Claudia-F. Lopez Camara from the group of Materials Chain member Hartmut Wiggers. The PhD students were supported in presenting their research results in a concise and appealing way. The results are impressive - in less than 90 seconds, viewers can learn about the research of two CENIDE PhD students.
Jil-Lorean's Elevator Pitch video showcases her work on the conversion of carbon dioxide to methanol. In just a few minutes, she gives a comprehensive overview of her research and its contribution to her field. Her passion and expertise on this topic are evident, making this video a must-see for anyone interested in sustainable energy solutions.
Varatharaja's Elevator Pitch video focuses on his research in sustainable electrocatalysts. He gives a glimpse into the world of his research topic and its potential impact in the future. This video is a great introduction to Varatharaja's work and the impact it could have for a more sustainable future.
https://www.uni-due.de/cenide/en/news-detail.php?id=innovative-research-in-elevator-pitch-videos
- MAT4HY gets Funding
25th April 2023,
Cooperation Platform "Materials for Future Hydrogen Technologies" funded by NRW. Read original article
(c) MKWResearchers led by Materials Chain members Prof. Dr. Ulf-Peter Apfel from the Ruhr-Universität Bochum and Prof. Dr. Doris Segets from the University of Duisburg-Essen, as well as employees of the Hydrogen and Fuel Cell Center ZBT, the IUTA and the Westfälische Hochschule are part of the cooperation platform "Materials for Future Hydrogen Technologies" (MAT4HY.NRW). The aim is to make hydrogen production by electrolysis, which is needed for the energy transition, scalable for large dimensions. To replace expensive precious metal-based catalysts, electrochemically active materials are to be developed that are suitable for large-scale industrial use due to their good availability.
The "Cooperation Platforms" funded by the state of North Rhine-Westphalia are intended to strengthen and expand existing, thematically focused cross-location networks of universities, universities of applied sciences and non-university research institutions in NRW with external cooperation partners. Materials Chain members Prof. Dr. Corina Andronescu, Prof. Dr. Stephan Barcikowski, Prof. Dr. Harry Hoster and Prof. Dr. Christof Schulz are also involved in the cooperation platform.
https://www.uni-due.de/2023-04-28-kooperationsplattform-wasserstoff-startet
- New profs at the Research Center Future Energy Materials and Systems
13th April 2023,
. Read original articleThree new professorships have been filled in Bochum and Duisburg-Essen, two of them with top-class female researchers. Gabi Schierning has held an RC FEMS professorship at the University of Duisburg-Essen since February 2023. Previously, she was a professor of experimental physics at Bielefeld University. “In addition to studying materials science and engineering, I have also researched fundamental questions in experimental solid-state physics,” she outlines. “My experimental research focuses on electron transport in solids. Optimised electron transport is essential in many energy materials, which is why I am a good fit for RC FEMS. Specifically, I’m currently studying the role of electrons in phase transformations of metals.” Gabi Schierning didn’t find it at all difficult to relocate to the Ruhr region. She’d already completed her habilitation at the University of Duisburg-Essen. “During that time, I got to know the university, many colleagues and also the Ruhr region, and I really enjoyed coming back,” she says. In her own words, the Research Alliance Ruhr and specifically the RC FEMS offer her “an excellent research environment, especially with the appointment of several top-class scientists to push the boundaries of research in material design.” At Ruhr-Universität Bochum, the two new professorships are held by Silvana Botti and Miguel Marques. Silvana Botti's research focus is on the theory of
(c) UDE - Nanotubes as an optical stopwatch
12th April 2023,
Detection of messenger substances. Read original article
© RUB, KramerPictured: Prof. Sebastian Kruß and Dr. Linda Sistemich from the RUB.
A new method to detect the important neurotransmitter dopamine in the brain has been developed by an interdisciplinary research team from Ruhr University Bochum (RUB) and University of Duisburg-Essen (UDE). They found that carbon nanotubes can be used virtually as optical stopwatches in the process. Their findings have now been published in the journal Angewandte Chemie - International Edition.
They used the tubes, which are 100,000 times thinner than a human hair, as sensors. When they come into contact with messenger substances such as dopamine in cells, they glow brighter. The researchers had already found this out in earlier studies. Now the research team led by RUB Prof. Sebastian Kruß has discovered that these carbon nanotubes, modified with certain biopolymers, then also shine longer. The duration of illumination can therefore be used as a measurement parameter in the detection of the messenger substance. And not just for this one. "We are convinced that this will open up a new platform that will also enable better detection of other human neurotransmitters such as serotonin," says Kruß.
Cells communicate with each other via the neurotransmitter dopamine. It not only controls the reward center, but is also the driving force for movement, coordination, concentration and mental performance. If too little dopamine is released, this can lead to movement disorders and declining memory - symptoms that occur, for example, in Parkinson's disease.
- Climate change in the Ruhr region
29th March 2023,
UDE4future Lecture Series. Read original article
© UDE4FutureClimate change affects us all. How we can counter it is the topic of the lecture series "I am changing! The Climate and Our Lives in the Ruhr Area 2035" at the UDE. The climate initiative UDE4future has invited not only researchers but also experts from politics and business. The event starts on April 20. All events will take place at the NETZ building.
How does climate-neutral steel production work and what impact does climate change have on water quality? And who actually owns our (environmental) world? What concept of ownership do we have when dealing with nature? As in previous years, the lecture series will examine climate issues at a regional level. In order to offer as many different perspectives as possible, UDE4future has invited experts from local authorities, business, politics and science.
- Why nickelates are superconducting
28th March 2023,
Origin revealed. Read original article
© Cornell UniversitySuperconductors can transmit electric current without loss over any distance and play an important role in quantum computers and medical imaging. A new promising materials class are the nickelates, nickel- and neodymium-based oxide compounds. Discovered in 2019, the underlying superconductivity mechanism remained so far elusive. A significant step forward in understanding its origin was achieved by an international team led by Cornell University (USA), including two theoretical physicists from the UDE. The discovery could help to produce new improved superconductors. The findings have just been published in Nature Materials*.
"Superconductors are the stars among electrical conductors," explains Materials Chain member Rossitza Pentcheva, professor of computational materials physics at UDE. "But they usually only work at extremely low temperatures, which makes technical applications difficult. Science is therefore looking for new classes of materials that are superconducting at higher temperatures." Over the past years, the focus has turned to the so-called nickelates, which were synthesized for the first time at Stanford University.
What makes these nickelates special is that superconductivity has so far only been detected in samples grown as very thin crystalline films - less than 20 nanometers thick - on a substrate. It was suspected that superconductivity only occurs where the thin nickel-oxide film meets the substrate on which it was grown.
To resolve this issue, an international team of physicists involving Pentcheva and her collaborator, Dr. Benjamin Geisler, combined experimental and theoretical methods, including scanning transmission electron microscopy, electron energy loss spectroscopy and quantum-mechanical simulations on high-performance computers.
https://www.uni-due.de/2023-03-28-why-nickelates-are-superconducting
- Material, listen!
27th March 2023,
Publication in Advanced Intelligent Systems. Read original article
© UDE/Robin Msiska"Seven, one, nine, …": A human voice speaks digits, and a material recognizes them correctly by about 97 percent. The pattern recognition system was developed by physicists at the UDE in collaboration with Ghent University (Belgium). The development made it possible to solve multidimensional problems quickly and without energy-consuming training. The journal Advanced Intelligent Systems reports.
Can a material recognize patterns quickly and efficiently? This question was asked by a team from theoretical physics, led by Professor Dr. Karin Everschor-Sitte. The researchers used speech recognition to prove that it works.
The team, led by first author Robin Msiska, used audio recordings of the spoken digits 0 to 9 from a standard database. The physicists analyzed at which point in the spoken word which frequencies are involved and how intensively. They converted this information into voltage signals, which they applied to a thin magnetic film via 39 contacts.
This material contains small magnetic vortices (skyrmions) that react to the voltage by deforming: "Simplified, you can imagine it like a black-and-white pattern that changes its shapes," Msiska clarifies. The material thus maps an individual pattern for each spoken number, which can then be read out linearly by a simple computer like a QR code.
- Model conception disproved
27th March 2023,
Hydrogen production by electrolysis. Read original article
© GDCh/Jürgen LöselPictured: In January, Prof. Kai S. Exner (right), who has already received several awards, was appointed to the board of the electrochemistry section of the German Chemical Society (GDCh).
Producing hydrogen from water and solar energy alone - researchers around the world are working on this sustainable path. Theoreticians support the development by identifying promising materials and methods. Materials Chain member Prof. Kai S. Exner from the Department of Theoretical Inorganic Chemistry at the UDE has now been able to demonstrate that previous modeling assumed mechanisms that were too simple and therefore did not provide reliable results. He published his analysis in the journal Materials Horizons.
Electrolysis takes place between two poles: The desired hydrogen (H2) is formed at the cathode, and oxygen (O2) is released in parallel at the anode. Both sides are interdependent, so one of the challenges facing research is as follows: The formation of H2 already works quite efficiently, but the oxygen gas evolution on the other side requires six to seven times the overvoltage, so this part of the process determines the energy efficiency.
Therefore, research is currently focusing on the anode. The aim is to develop better materials for this that are sufficiently active and stable even at a lower overvoltage. This development work is accompanied by theoretical modeling that works with approximations and assumptions.
One of the putative paradigms so far has been the assumption that the process of oxygen gas evolution is based on a single mechanism involving three defined intermediates. Prof. Kai S. Exner, a theoretical electrochemist at University of Duisburg-Essen, was the first to challenge this assumption: "In the literature, I found evidence for other mechanisms involved - six different ones in total."
He then constructed volcano curves for all six mechanisms - a concept from catalysis research - to capture activity trends. His finding: only inactive catalysts can be modeled using the previous single mechanism model. For the crucial highly active catalysts, on the other hand, the mechanisms merge into one another with increasing overvoltage.
Just recently, Kai Exner was awarded the Carl Duisberg Memorial Prize. The prize, endowed with 7,500 euros, has been awarded by the German Chemical Society (GDCh) since 1936 to young university teachers working at a German university or as Germans at a university abroad. This year, Kai Exner is being honored for his outstanding contributions to theoretical electrocatalysis and battery research.
https://www.uni-due.de/2023-03-27-mehr-mechanismen-in-wasserstofferzeugung-beteiligt
- Defects in Two-dimensional Materials
3rd March 2023,
750th WE-Heraeus Seminar. Read original article
(c) WE-HeraeusThe 750th WE-Heraeus Seminar on "Defects in Two-dimensional Materials" will be held May 8-12 at the Physikzentrum Bad Honnef.
The seminar will focus on the study of defects in two-dimensional materials, which have recently been the focus of research in materials science, physics, and chemistry. Defects have a strong influence on the electronic, optical, thermal, and mechanical properties of solids. While they often degrade the properties of a material, they can also be useful, for example, in semiconductor doping or quantum computing. The goal of this seminar is to bring together researchers:in the field to discuss the "state of the art" in theory and experiment dealing with the physics of defects in 2D materials. Participants will be introduced to the latest developments in theoretical methods and characterization techniques for studying defects in 2D materials. The effects of various imperfections on the properties of 2D systems will be addressed, with a particular focus on defects in technologically important graphene and transition metal dichalcogenides. The conference language is English, and thanks to the Wilhelm and Else Heraeus Foundation, the cost of full-board accommodation will be covered for all participants.https://www.we-heraeus-stiftung.de/veranstaltungen/defects-in-two-dimensional-materials/application/
- Chancellor at ZBT
3rd March 2023,
Olaf Scholz informs himself about hydrogen. Read original article
Copyright: Bundesregierung / BergmannChancellor Olaf Scholz and Bundestag President Bärbel Bas took an hour and a half to visit the Center for Fuel Cell Technology (ZBT) at the University of Duisburg-Essen on Tuesday afternoon. At the hydrogen test field in the middle of the Duisburg campus, the chancellor showed great interest in the energy carrier of the future, asked questions about facilities to the right and left of the pre-planned path, and exchanged ideas with young researchers.
Scholz emphasized the great importance of green hydrogen for the future of Germany and Europe. To achieve this, he said, production must now leave the laboratory: "We need discussions about industrialization paths." In various laboratories and in discussions with ZBT scientists, Scholz gained an overview of the high-tech infrastructure and the aspects for ramping up a sustainable hydrogen economy. "Duisburg is home to first-class high technology and science; the kind we need for our common future." In the subsequent round with students and doctoral candidates, the Chancellor also showed that he had taken a close look at the topic. The questions went right to the heart of the matter: the amount of funding, too much bureaucracy, future transportation systems. But the young researchers also demanded clear statements from Scholz on the German government's climate policy. "The visit of the Federal Chancellor is a special honor for us," summarizes ZBT Managing Director Dr. Peter Beckhaus. "Especially the direct and intensive exchange with the scientists was excellent for both sides and fundamental for the next steps. Only in solidarity between industry, politics and science will we get the hydrogen economy established in Germany and thus substantially secure employment." With the Hydrogen Center TrHy (The Hydrogen Proving Area), Duisburg is one of the four locations of the nationwide Innovation and Technology Center for Hydrogen. - Lecture series 2023
3rd March 2023,
I am changing! The climate and our lives in the Ruhr region in 2035. Read original article
For the third time, the University of Duisburg-Essen presents its annual lecture series on climate change entitled "Ich wandle mich! The climate and our lives in the Ruhr region 2035". This informative and thought-provoking event will focus on current research findings and scientific reflections on necessary changes in the Ruhr region with the aim of promoting a technical and socio-ecological transformation.
The UDE4future initiative places great emphasis on creating access to this complex topic and making the presentations accessible to as many interested parties as possible. Experts will be available for dialogue and discussion to discuss the challenges and positive aspects of climate change.
The lecture series will take place every Thursday at 4 p.m. starting April 20 in the NETZ building. The lectures will also be broadcast online via Zoom. Separate registration, whether attending in person or online, is required for each lecture.https://www.uni-due.de/cenide/en/news-detail.php?id=lecture-series-2023
- Silicon-carbon anodes for more powerful lithium-ion batteries
24th February 2023,
EU funding for UDE. Read original article
© PCC SEThe Duisburg-based PCC Group company PCC Thorion GmbH and its research partners, the Fraunhofer Institute for Solar Energy Systems ISE, the Albert Ludwigs University of Freiburg and the Center for Nanointegration Duisburg-Essen (CENIDE) of the University of Duisburg-Essen, have launched a research project aimed at enhancing the performance of lithium-ion batteries. EU funding of 3.5 million euros is being used for the project. The aim is to scale up to industrial scale the production of the innovative silicon-carbon composite developed by PCC Thorion and Fraunhofer ISE as anode material and silicon nanoparticles suitable for this purpose.
A composite material developed by PCC Thorion and Fraunhofer ISE, which is considered a particularly effective anode active material for lithium-ion batteries, increases their capacity and enables longer ranges and shorter charging times. The material, a silicon-carbon composite, can be easily integrated into existing manufacturing processes and has shown exceptional results in terms of specific capacity and cycling stability. With this silicon-carbon composite, the collaboration partners aim to provide the fast-growing battery industry with a drop-in material that can be easily integrated into existing manufacturing processes and replace the graphite anode material that has been used to date. The consortium has also begun work on complete battery cells. With EU funding, the conditions are in place to expand and scale up production. The raw material silicon for the composite is produced by PCC BakkiSilicon exclusively from renewable energy sources, significantly reducing the carbon footprint of the material. Commercially, the batteries could be used in electric cars, particularly if charging times are reduced and range extended. - Less Greenhouse Gases through Hydrogen Engines
24th February 2023,
DFG funding for engineering sciences. Read original article
scharfsinn86 – stock.adobe.comHydrogen can be used CO2-free not only in fuel cells, but also in engines to power vehicles. How such hydrogen engines can run smoothly and efficiently is being researched by several universities led by the UDE in a project that, in its second funding period, is looking at the use of hydrogen in gasoline engines. The German Research Foundation (DFG) is funding it with about 2.8 million euros, 852,000 of which will go to the UDE.
Since 2019, the four universities of Aachen, Darmstadt, Duisburg-Essen and Stuttgart have been investigating how the combustion process in car engines can be optimized. While the first funding period focused on conventional gasoline fuels, the scientists are now researching hydrogen as an alternative fuel. The project is divided among the universities into seven subprojects. Two of them are at the UDE, which also provides the project spokesperson, Prof. Dr. Sebastian Kaiser. His group is currently investigating the mixing of fuel and air in experiments using optical measurement techniques in the engine cylinder. Together with ignition, this process is one of the main influences on cyclic fluctuations. In the second subproject, a team led by Materials Chain member UDE professor Andreas Kempf is using simulations to analyze how cyclic fluctuations and the stability of the engine process change when the components of the fuel are varied. “The goal of our projects is to be able to predict the irregular combustion processes and fluctuations. Then we could develop appropriate countermeasures to optimize hydrogen engines in efficiency and reliability,” Professor Kaiser said.https://www.uni-due.org/presse/weniger-treibhausgase-durch-wasserstoffmotoren/
- Quantum Tech Workshop at CENIDE
24th February 2023,
Experts to present latest research on February 24th. Read original article
(c) CENIDEQuantum technologies is an emerging field of engineering, physics, and computer science encompassing technologies that rely on the properties of quantum mechanics, especially quantum entanglement, quantum superposition, and quantum tunneling. Researchers and experts in the field of quantum technologies are invited to participate in the CENIDE Quantum Tech Workshop on February 24, 2023 from 1 – 4 p.m at the NETZ 2.42. The event, which was originally scheduled for Dec. 9 but had to be canceled due to the cyberattack, will focus on discussing the latest development and research in quantum technologies.
The workshop will feature talks by researchers from CENIDE, UDE and Frauenhofer IMS from a variety of disciplines, including physics, engineering and computer science, on topics such as quantum computing, sensors, cryptography, simulation, measurement and imaging. Participants will have the opportunity to present their own research experiences in quantum technologies in a short 5-minute talk. All those interested in the field of quantum technologies are invited to learn about the latest advances and exchange ideas with other experts in the field.https://www.uni-due.de/cenide/en/news-detail.php?id=quantum-tech-workshop-bei-cenide
- Green hydrogen
24th February 2023,
Nanocubes as optimal catalysts. Read original article
© AG NanoEC/RUBFor the production of green hydrogen to gain momentum, one thing above all is needed: nanoparticles that act as catalysts to control the process of splitting water into oxygen and hydrogen. The particles should be inexpensive, effective and environmentally compatible – and cube-shaped. This is what researchers from University of Duisburg-Essen (UDE) and Ruhr University Bochum (RUB) have now discovered. Their proof that cube-shaped nanoparticles are much more effective than spherical ones paves the way for the targeted design of efficient catalysts for green hydrogen. They reported on their findings in the scientific journal Advanced Functional Materials*.
Precious metals such as platinum or iridium are rare and expensive, but so far they are the most effective catalysts for the production of green hydrogen. A team led by the Materials Chain members Prof. Dr. Kristina Tschulik (RUB) and Prof. Dr. Rossitza Pentcheva (UDE) have set themselves the task of changing that. In the researchers’ focus: Oxide nanoparticles made of base metal, such as cobalt oxide. They come into question as catalysts for the half-reaction of water splitting, namely for the formation of oxygen. “Oxygen evolution as a partial reaction of the so-called water electrolysis is much more complex than hydrogen evolution and thus represents a bottleneck effect for the production of green hydrogen ” says Pentcheva. The team around Kristina Tschulik has developed a method to analyze individual particles directly in solution. This makes it possible to compare the activity of different nanomaterials with each other and thus elucidate the influence of particle properties, such as their shape and composition, on water splitting. The result: the surface of cube-shaped cobalt oxide nanoparticles is much more active in the formation of oxygen than the surfaces of their spherical counterparts. Through quantum mechanical simulations, including on the supercomputer at UDE, Rossitza Pentcheva’s team provides an explanation for the phenomenon and a deeper insight into the underlying mechanism: the higher catalytic activity of the cubic nanoparticles compared to the spherical ones is due to the different active sites on the two surfaces. “Understanding at the atomic level how the crystallographic orientation of the surface and the catalytic activity are related is the basis for the targeted design of new catalysts,” physicist Pentcheva says. To original publication: https://onlinelibrary.wiley.com/doi/10.1002/adfm.202370006 - Microstructural Functionality at the Nanoscale Workshop in Venice, Italy
24th February 2023,
3rd MiFuN in a series. Read original article
From June 8 to 9, 2023, the workshop “Microstructural Functionality at the Nanoscale” (MiFuN III) will take place in Venice for the third time. The workshop is organized by CENIDE members Prof. Dr. Markus Winterer (University of Duisburg-Essen) and Materials Chain member Prof. Dr. Dietrich Wolf (Universtiy of Duisburg-Essen) and Prof. Dr. Umberto Anselmi-Tamberuni (University of Pavia).
MiFuN II is the third in a series of international workshops on the time dependence of structural features at the nanoscale. It covers recent research topics with strong impact on nanoscience and nanotechnology. Mechanisms for microstructural evolution range from the formation of defects, their transport, growth and transformation, to segregation, sintering and cooperative mechanisms including the controlled manipulation of grain boundaries and other microstructural elements in nanocrystalline materials. These mechanisms can lead to novel dynamic functionality, such as resistive switching or self-healing and are also determining the lifetime of nanostructured devices such as batteries or solar cells. - CENIDE members in current edition of the NMWP magazine
24th February 2023,
Articles by Franziska Muckel as well as Friedrich Waag and Sven Reichenberger. Read original article
The current edition of the Magazine for Nanotechnology, Microsystems Engineering, New Materials, Photonics and Quantum Technology (NMWP) also features two articles by CENIDE members.
First, Franziska Muckel writes about the potentials of MHPs in photonics and optoelectronics in her article “Metal halide perovskites with tunable optical properties for tomorrow’s optoelectronics”, and second, Friedrich Waag and Sven Reichenberger wrote the article “The power of light – catalyst design with lasers” about a scalable and automatable laser process for the design of low noble metal catalyst materials. The articles can be read at the links below. - “Advanced Catalysis and Materials for Energy Conversion“ – ACAMEC
24th February 2023,
IMPRS-RECHARGE 4th Symposium. Read original article
From April 24 – 27, 2023, the fourth IMPRS-RECHARGE Symposium will be held under the title: “Advanced Catalysis and Materials for Energy Conversion” – ACAMEC”. The symposium on catalytic techniques for energy and transportation systems is a must-attend event for anyone interested in the future of energy and the environment. With a focus on optimization and upscaling of current approaches to industrial standards, the symposium brings together experts from academia and industry to share their findings and breakthroughs.
Attendees will have the opportunity to learn about the latest developments in catalyst technologies as well as key challenges in the field. The event also provides a platform for PhD students to present their own research and interact with experts in the field. A wide range of topics will be covered, including the generation, distribution, storage and consumption of energy in a decentralized manner, as well as advanced batteries and energy storage materials. The event will also explore the economics and environmental aspects of current catalytic approaches on a larger scale. The event will provide a unique opportunity for participants to gain a deeper understanding and network with some of the leading minds in the field. - Junges Kolleg NRW: Corina Andronescu new member
24th February 2023,
Materials Chain member Corina Andronescu. Read original article
© UDE/Bettina Engel-AlbustinThe earth’s temperature is rising – and rapidly. This makes it all the more important to move away from fossil fuels and switch completely to sustainable energies. Among others, Materials Chain member Jun.-Prof. Dr. Corina Andronescu from the University of Duisburg-Essen (UDE) is investigating how helpful hydrogen is in this process. For her research, she was accepted into the Young College (Junges Kolleg NRW) of the North Rhine-Westphalian Academy of Sciences and Arts.
Sourcing energy sustainably and reducing carbon dioxide (CO2) emissions: Both times, electrochemical processes and applications such as hydrogen generation play a crucial role. They work via electrolysis, which breaks down chemical substances into their constituent materials. “Electrolysis is the only way to produce hydrogen from water in a climate-neutral way – as long as green energy is used for this. For climate protection reasons, however, it makes extreme sense,” says chemical engineer Andronescu. Hydrogen is used in particular in the chemical industry and to power vehicles. In the Young Scientists Group of the NRW Academy, the 35-year-old will focus on researching electrocatalysts that accelerate electrolysis. To this end, her group is focusing on non-precious metals such as nickel, which can be used to split water and thus generate hydrogen (H2). During the four-year collegiate funding, the UDE professor also wants to find out more about the design of electrodes. Why? “If we want to recycle CO2 electrolytically to enable the synthesis of its basic chemicals, their design is extremely important. We aim to combine different catalysts to increase CO2 conversion into multi-carbon products such as ethanol ethylene. Stability is also important,” she explains. At the same time, Andronescu wants to find materials for electrochemically driven reactions that can be used to synthesize chemicals. “We need to learn to synthesize basic chemicals that are currently derived from fossil fuels from resources that are abundant in the earth, such as CO2, H2O or nitrogen (N2). The novel materials are important to enable the transformation of these molecules. Because of climate change, we need to accelerate discoveries.” To do this, she uses high-throughput electrochemical screening methods to study up to thousands of different catalysts a day. “We can identify promising catalyst materials more quickly. In the future, AI integration will also be required, but we’re not there yet.”https://www.uni-due.org/presse/junges-kolleg-nrw-corina-andronescu-neues-mitglied/
- Digital reordering of the World
25th November 2022,
Research Project on chipless RFID. Read original article
© andreydesign - stock.adobe.comWhether in ID cards, vehicles, animals or sometimes even people, RFID technology ("Radio-Frequency Identification") often remains invisible, but is almost everywhere. Prices, names, dates of birth or biometric characteristics are stored on them. A new technology that makes it possible to produce RFID tags without chips and attach them inexpensively to almost any object is now the focus of a research project at the University of Paderborn and the UDE. They are investigating the opportunities and challenges of the technology.
The manufacturing costs of chipless, printable radio tags are significantly lower than variants with chips. The technology also makes it possible to individualize, identify and track all material goods. The technology thus offers potential for logistical and business organization processes, but on the other hand it harbors risks for privacy and data protection.
The two-year "UbiTag" research project started in July and is funded by the German Federal Ministry of Education and Research (BMBF) with around 300,000 euros. It is being run under the direction of Prof. Jutta Weber from the Institute of Media Studies at the University of Paderborn in collaboration with Materials Chain member Daniel Erni, UDE professor of General and Theoretical Electrical Engineering.
- Future Perspectives of the Knowledge Region
25th November 2022,
Municipal council consults with UA Ruhr. Read original article
© Stadt Bottrop
Pictured: UDE Rector Prof. Barbara Albert (4th from left), TU Dortmund University Rector Prof. Manfred Bayer (3rd from left), and RUB Rector Prof. Martin Paul (5th from left) with the members of the Local Council.Top administration meets science: The council of municipalities in the Ruhr Regional Association (RVR) met for the first time with the management trio of the Ruhr University Alliance (UA) to discuss issues concerning the future and location of the region. The committee consists of eleven mayors, four district councils and regional director Karola Geiß-Netthöfel. The UA Ruhr rectors Prof. Barbara Albert (University of Duisburg-Essen), Prof. Martin Paul (Ruhr University Bochum) and Prof. Manfred Bayer (TU Dortmund University) took part in their discussions in Bottrop.
"Education and innovation are of central importance for a future-oriented transformation of the Metropole Ruhr into one of the leading knowledge locations in Germany. Knowledge is the new raw material of the Ruhr region," emphasized Bochum's Mayor Thomas Eiskirch, Chairman of the Municipal Council, after the meeting with the UA Ruhr. In the competition for the brightest minds, 17 colleges, five universities and more than 50 non-university institutes with more than 250,000 students make the Ruhr the metropolitan region in Germany with the most universities. Eiskirch continues: "We want to use this advantage. After all, it is not only the jobs of tomorrow that are created in the vicinity of the universities. Together with the Ruhr science landscape, we also want to provide impetus for innovative urban development."
In the Municipal Council, the rectors presented, among other things, how the cooperation of the three universities of Bochum, Dortmund and Duisburg-Essen under the umbrella of the UA Ruhr has been working since 2007. The type and scope of this cooperation is unique in Germany. Due to the intensive cooperation, the UA Ruhr recently convinced the Ruhr Conference with its concept of the Research Alliance Ruhr and received a corresponding state funding of 75 million euros. The four joint research centers and one college build on existing strengths. These will be further expanded through the appointment of up to 50 internationally renowned top scientists.
The three university leaders agree: "With the Research Alliance, we are strengthening the international visibility of our research. In addition, we are creating innovations and driving forward the transformation of the region. With our cooperation, we are among the pioneers of an increasingly coalescing Ruhr region that can hold its own in international competition."
Through the interplay of university education, research, business development and the development of urban neighborhoods, the Ruhr Area municipalities and the UA Ruhr also see great potential for new businesses and start-ups. More than 15,000 graduates per year provide the region's labor market with urgently needed talent and skilled workers.
Thomas Eiskirch, as chairman of the local council, announced: "We will also continue the dialogue started today in Bottrop with the other players in the Ruhr knowledge region, such as universities of applied sciences and non-university research institutions."
https://www.uni-due.de/2022-11-24-ua-ruhr-fuehrung-trifft-kommunalrat-im-rvr
- NETZ with Roll-to-Roll Coater in University of Duisburg-Essen Research Magazine
22nd November 2022,
Tetris for Industry. Read original article
In the current edition of the research magazine of the University of Duisburg-Essen (UDE), NanoEnergieTechnikZentrum (NETZ) is featured with the modular Roll-to-Roll-Coater. The pilot plant, whose individual cuboids can be assembled in different ways as required and which is normally only used by technically oriented institutes or directly in industry for preliminary tests, is the subject of an article entitled "Tetris for Industry".
Interested parties can read the article under the following link
https://forschungsmagazin.online/de/tetris-fuer-die-industrie/
- Young Top Researcher Honored
3rd November 2022,
Gottschalk-Diederich-Baedeker Prize. Read original article
© UDE/Juliana FischerShe develops energy-efficient methods to produce hydrogen for the energy transition or to bind climate-damaging carbon dioxide: Materials Chain member Prof. Dr. Corina Andronescu. Now the UDE chemist has received the Gottschalk-Diederich-Baedeker Prize. This prize is awarded by the Essen-based G.D. Baedeker Foundation to scientists who bring their outstanding research to industry. The prize money is 5,000 euros.
With the prize, the foundation wants to make the benefits of UDE research visible for the Ruhr metropolitan region. Corina Andronescu's work is a perfect example of this. This is because the 35-year-old is investigating how, for example, catalytic hydrogen production can also become more sustainable on a larger scale in the future. "The industry is working on a large scale. So that expensive and rare raw materials can be avoided here, I am researching new materials in the hydrogen production process," says Andronescu. "In particular, I want to replace the precious metals platinum and iridium in the membranes and electrodes of the standard electrolysis chambers with more sustainable and cheaper base metals."
Moreover, so far only the purest water can be used to produce hydrogen - which is scarce and requires energy-intensive processing. For this reason, the electrochemist is also investigating what water quality still works in electrocatalytic processes without damaging the materials. She is also developing new types of catalyst materials to bind climate-damaging CO2 in order to produce useful basic chemicals such as ethanol or ethylene.
UDE Rector Prof. Dr. Barbara Albert, Martin Sutter, board member of the G.D. Baedeker Foundation, and Essen's Mayor Thomas Kufen were impressed by the young scientist's commitment at the award ceremony. Laudator and Materials Chain member Prof. Dr. Stephan Barcikowski was particularly pleased with the "double whammy" that Andronescu brings to the Faculty of Chemistry. She received the prestigious Joachim Walter Schultze Award from the Association of Electrochemical Research Institutions just in September.
Andronescu has been at UDE since 2018 and is well connected in the research community. She is vice speaker of ACTIVES SITES, a research building currently under construction at the Essen campus. Here, active centers in aqueous environments are being researched, which play an important role in chemical and biological processes, for example also in electrochemical energy conversion.
- Materials Chain Member Interviewed About E-fuels
3rd November 2022,
Prof. Dr. Ulf-Peter Apfel on Deutschlandfunk Radio. Read original article
The latest episode of Deutschlandsfunk's format "Tolle Idee!" (Great Idea!) deals with climate-friendly fuels, so-called e-fuels, and how they might be produced from CO2. Materials Chain Member Dr. Ulf-Peter Apfel, professor for Inorganic Chemistry at Ruhr University Bochum and Head of Department Electrosynthesis at Fraunhofer UMSICHT, contributes to this topic by discussing Fischer-Tropsch synthesis and catalysts. You can listen to the episode at the link below.
Prof. Apfel is also one of the leading scientists in DIMENSION, a 3-year collaborative research project between the University of Duisburg-Essen and the Ruhr-University Bochum. DIMENSION aims at exploration, synthesis and relevant testing of new functional materials for electrochemical energy systems.
- Research on tiny Magnets
20th September 2022,
Humboldt Award Winner chooses University of Duisburg-Essen. Read original article
(c) privatProf. Hari Srikanth (University of South Florida, USA) is one of only five researchers to receive the 2022 Humboldt Research Award. The award is linked to a research stay at a German institute of his choice. Srikanth has chosen to pursue physics at University of Duisburg-Essen (UDE). In particular, his work complements the spectrum of the large research network TRR270 "HoMMage" on magnetic materials for efficient energy conversion.
Hari Srikanth conducts research in the field of magnetic nanoscale structures. Until August 2023, he will research novel interfaces in magnetic particles as well as two-dimensional systems in the group of Materials-Chain member Prof. Michael Farle, co-spokesperson of "HoMMAge". Both are crucial for the development of energy-efficient information processing, magnetic cooling and biomedical diagnostics and therapy.
In tumor treatment, for example, magnetic nanoparticles are injected into diseased tissue. There they are set in vibration and heated so that they destroy diseased cells locally. This requires particles that cannot overheat, are non-toxic and have special shapes and magnetic properties. Interfaces come into play especially in ultrathin magnetic films, which are supposed to be the next, energy-saving generation after the current electron-charge-based information processing. After all, if we understand the processes at the interfaces, the magnetic properties can also be better controlled.
The Humboldt Research Award is granted exclusively to scientists from abroad for their overall work, who have left a lasting mark on their field and from whom top achievements can be expected in the future. The award, which is endowed with 60,000 euros, enables them to spend six to twelve months researching in a working group of their choice in Germany.
Further information:
Prof. Dr. Michael Farle, Faculty of Physics, Tel. 0203/37 9-2075, michael.farle@uni-due.dehttps://www.uni-due.de/2022-09-19-us-physiker-entscheidet-sich-fuer-ude
- Replacement Parts for the Body
14th September 2022,
Conference of the Society for Biomaterials. Read original article
They are researching how human organs can be manufactured using 3D printing and developing materials for modern medicine: researchers who have dedicated themselves to biomaterials. From September 15 to 17, more than 180 of them will meet in Essen for the annual conference of the German Society for Biomaterials.
Biomaterials science implants are widely used in medicine. Hip prostheses, knee prostheses, dental implants, pacemakers, dentures, surgical screws and plates are just a few examples. Today, such implants are no longer available only "off the shelf." "The 3D printing process makes it possible to individually adapt implants to the patient, an enormous medical advance," emphasizes conference leader and Materials-Chain member Prof. Dr. Matthias Epple from the UDE. 3D printing is a central topic of the conference program, as are innovations for infection prevention and the targeted administration of active substances in the vicinity of implants. Special antibacterial coatings on implants can better prevent postoperative infections. The full program can be found here.
Further information:
Prof. Dr. Matthias Epple, Faculty of Chemistry, Tel. (0201) 183-2413, matthias.epple@uni-due.de
https://www.uni-due.de/cenide/news-detail.php?id=ersatzteile-fuer-den-koerper
- 8th RUHR-Symposium
9th September 2022,
Functional Materials for Hydrogen. Read original article
The successful format of the Ruhr-Symposium will be held for the eighth time this year on October 19. The event, which is characterized by the combination of representatives from science and industry in tandem sessions, is dedicated this year to the topic "Functional Materials for Hydrogen".
This year, the symposium is themed " Functional Materials for Hydrogen " and will take place on Wednesday, October 19, at the Fraunhofer-InHaus-Center in Duisburg. The event is characterized by tandem sessions in each of which an academic speaker is paired with an industry speaker followed by a plenary discussion. Please note that some talks will be in German, others in English.
This year, following the conference, the "Duisburger Zukunftsgespräche" will take place at the same location starting at 7 pm. These are open to the public and can also be attended independently of the Ruhr-Symposium.
- Climate-friendly Steel
7th September 2022,
Recycling CO2 in the Blast Furnace. Read original article
© worldsteel/thyssenkrupp steel, GermanyPictured: Coke oven in the integrated iron and steel mill of thyssenkrupp Steel Europe AG in Duisburg-Bruckhausen: Here volatile hydrocarbons are removed from the coal to recover carbon for use in the blast furnace.
Germany is the largest steel producer in the EU. Around a third of the carbon dioxide (CO2) emitted by all industry in Germany is produced in blast furnaces. But an alternative process route is in sight that produces almost no CO2. However, it will take many years before it is fully established. Under the coordination of the University of Duisburg-Essen (UDE), engineers are developing a concept for recycling the CO2 that is produced. The project is being funded by the German Federal Ministry of Education and Research.
In the coming decades, the large steel companies will switch to direct reduction plants, which will initially be operated with natural gas and later with hydrogen. In this process, iron ore is reduced to iron with the help of hydrogen. The subsequent melting process uses electricity generated from renewable sources. The resulting CO2 emissions are negligible at around 30 kg per ton of crude steel. But it will be decades before the corresponding infrastructure - from hydrogen production to predominantly CO2-free electricity generation - is fully in place.
In the transition phase, direct reduction produces high-purity CO2 as a byproduct that is to be reused in blast furnaces. In the next 20 to 30 years, the classic and new processes will coexist.
Engineers from the UDE are therefore working with thyssenkrupp Steel Europe AG and TU Clausthal to develop a concept for recycling CO2 directly in the process in the short term. The aim of the "NuCOWin" project is to answer the fundamental questions of process and plant technology for implementation on an industrial scale.
"The big challenge is to develop economical processes within the transformation in the steel industry, but also in other industrial sectors, that no longer release CO2 into the atmosphere," explains project leader Prof. Dr.-Ing. Rüdiger Deike from the UDE Institute for Technologies of Metals. "To do this, one should understand: Due to their high energy density, carbon compounds will continue to be indispensable, but the CO2 will remain in the cycle."
Within the funding program "KlimPro: Avoidance of climate-relevant process emissions in industry," the German Federal Ministry of Education and Research is funding the just-launched project for three years with a total of 1.2 million euros.
- Chemical reactions on film
31st August 2022,
Katrin F. Domke new at the University of Duisburg-Essen. Read original article
© UDE/Bettina Engel-AlbustinProf. Dr. Katrin F. Domke has accepted the professorship of Physical Chemistry of Liquid-Solid Interfaces in Heterogeneous Catalysis and Chemical Energy Conversion. She conducts research at the UDE Faculty of Chemistry on how to optimize the conversion of energy. When analyzing chemical processes, Domke focuses on atoms and molecules. So-called electrochemical tip-enhanced Raman nanoscopy (EC-TERS) makes it possible to image and characterize tiny structures of less than 10 nm in size under reaction conditions. The award-winning chemist developed and tested the method at the Max Planck Institute for Polymer Research in Mainz, Germany.
"We film in detail at the nanoscale how, where and when, for example, individual molecules are chemically and energetically transformed at solid-liquid interfaces," she explains. Solid-liquid interfaces exist in most chemical energy conversion systems, for example in fuel cells, where catalysts drive the energy conversion process. At UDE, the results of her research will contribute, among other things, to understand the interaction of solids, molecules and liquids at the atomic level, so that energy conversion processes can be optimized to enable more sustainable energy production.
During her chemistry studies (1998-2004) at the University of Bonn, Domke was involved in several months of research at the Spanish universities in Alicante (2001) and Seville (2002). After graduation, she did research at the Fritz Haber Institute of the Max Planck Society and received her PhD with honors from the FU Berlin in 2006. After postdoctoral stays at the Swiss University of Bern and at the AMOLF research institute of the Netherlands Research Council, she headed an independent junior research group at the Max Planck Institute for Polymer Research from 2012.
https://www.uni-due.de/2022-08-30-chemische-reaktion-film-katrindomke
- International Raman Innovation Award for Prof. Schlücker
25th August 2022,
Award for UDE chemist. Read original article
(c) Schlücker/UDEThe International Conference on Raman Spectroscopy (ICORS) takes place every two years. After 2018 in Korea and the cancellation in 2020 due to pandemic, for 2022 the two organizers from UC Irvine had chosen the Conference Meeting Center in sunny Long Beach, California as the venue. Three prestigious Raman awards were presented after selection by the International Steering Committee, including "The Raman Award for the Most Innovative Technological Development." This award went to Materials Chain member Prof. Sebastian Schlücker from the Physical Chemistry Department of the University of Duisburg-Essen (photo, 1 from left) for the development of a compact and fast Raman readout device for highly sensitive on-site diagnostics using nanotechnology and laser light.
With the reagents developed in Schlücker's group and this readout device, rapid tests in which gold nanoparticles are used because of their red color could be made orders of magnitude more sensitive in the future: this will make it possible to detect infections and diseases much earlier on site, saving time and money, since the samples do not have to be sent to a laboratory. A poster prize also went to physical chemistry: Helene Giesler, PhD student and FCI scholarship holder in the Schlücker group, presented work carried out within the SFB 1093 in cooperation with the group of Materials Chain Member Prof. Barbara Saccà, which convinced the international selection committee. - Transporting Hydrogen as Iron
10th August 2022,
Safe and Efficient. Read original article
(c) UDE/Silke RinkThe transport of green-generated energy in the form of iron. This is the vision of the "Me2H2 iron-steam process" project coordinated by the University of Duisburg-Essen. Hydrogen generated by means of solar energy, a chemical reaction and transport in metal form lead to a sustainable cycle. Together with partners from Clausthal and Bremen and associated industrial partners, the team aims to develop a concept for implementation on an industrial scale and has received funding from the German Federal Ministry of Education and Research (BMBF).
While one option is to store and transport hydrogen as ammonia, the team led by Dr.-Ing. Rüdiger Deike, UDE professor of metallurgy and forming technology, is instead pursuing an approach whose cycle could look like this, for example:
At a location with high solar radiation and readily available water resources, photovoltaic systems supply electrical energy. This is used to split water into oxygen and H2. Now only iron oxide is added for the subsequent chemical reaction. Here, reduction with hydrogen produces iron, which can be transported in the form of mini-briquettes or spherical pellets without environmental risk. At the destination, the reverse reaction is initiated to obtain hydrogen and iron oxide again.
The engineering team's main goal is to find suitable iron alloys that can undergo the chemical reactions as many times as possible without losses. "To develop the most efficient combination - of the best material systems and the process technology adapted to them," explains project coordinator Deike.
The BMBF is funding the project, which has just started, for three years with a total of 1.3 million euros as part of the "Hydrogen Republic of Germany" ideas competition. In addition to the UDE engineers, the Clausthal University of Technology and the Leibniz Institute for Materials-Oriented Technologies (IWT) in Bremen are also involved. Associated partners are thyssenkrupp Steel Europe AG and SMS group GmbH.
https://www.uni-due.de/2022-08-08-wasserstoff-als-eisen-transportieren
- Magnetic and Superconducting Materials
27th July 2022,
International Conference. Read original article
Magnetism on the nanoscale, magnetic materials in biology and medicine, 2D superconductors: these and other topics will be addressed by experts from all over the world at the International Conference on Magnetic and Superconducting Materials (MSM22) from August 28 to September 2 at the campus in Duisburg of the University of Duisburg-Essen (UDE).
In keynote and guest lectures, leading experts from Europe, Asia and the USA will present the latest developments in the field of fundamental and applied magnetism and superconductivity. There will also be a poster session.
The conference has been held every two years since 1999. UDE professor of the Faculty of Physics and Materials Chain member Michael Farle now succeeded in bringing it to Central Europe for the first time.
Interested parties can still register until August 1.Further information:
Registration and abstract submission: https://www.uni-due.de/msm22/registration.php
Updates via: MSM22-organizer@uni-due.dehttps://www.uni-due.de/2022-07-20-international-conference-on-magnetic-and-superconducting-materials
- ACTIVE SITES: New Methods for top-level Research
20th July 2022,
Research Building approved. Read original article
(c) Campus+Partner AGFunding for the new ACTIVE SITES research building has been secured: Following the Science Council, the Joint Science Conference (GWK) has now also given green light for the new 70-million-euro building. The two Materials Chain members Prof. Corina Andronescu and Prof. Dr.-Ing. Stephan Barcikowski were in charge of the application. The costs are shared by the federal and state governments and the University of Duisburg-Essen (UDE). With ACTIVE SITES the UDE gains a centre of international renown at which so-called active sites are researched in an aqueous environment. These have an important role in chemical and biological processes, such as energy conversion, water purification and active subtances development. Starting 2026, scientists from various disciplines will conduct research together in state-of-the-art laboratories.
"The concept for the new research building had already been rated as 'outstanding' by the Science Council," says Rector Prof. Barbara Albert. "The final decision for funding by the GWK is a great success and confirmation that we are on the right track."
The goal of the project is to develop new methods based on large-scale instruments that use knowledge from different disciplines to study active centres. Active sites are understood to be binding and reaction sites for molecules. The challenge here is to observe the course of reactions live and in their natural environment. "Until now, active sites have mostly been analyzed either in artificial environments or only indirectly, by comparing them before and after the reaction," explains Prof. Corina Andronescu, a technical chemist and deputy spokesperson of ACTIVE SITES. "We want to visualize the reaction in the natural aqueous environment. To do this, we will develop a set of methods that specifically brings together and combines expertise from the different fields of chemistry, biology, physics and engineering. This approach of working across disciplines as well as across substances is unique so far."
The knowledge gained can be used to influence reactions and steer them in desired directions. In this way, basic research could help to find answers to currently pressing questions, such as how individual cells in the ecosystem or even global biogeochemical cycles can be deciphered. Many industry-relevant processes are also likely to benefit from the new set of methods: processes such as Carbon Dioxide reduction or hydrogen production could be improved.
The new building will reflect the interdisciplinary approach. The plans contain many open work spaces and shared laboratories. These are intended to encourage exchange and can be flexibly adapted to the needs of different research groups. The building will be constructed on the site Am Thurmfeld, which is adjacent to the north of the existing campus in Essen. Construction is scheduled to begin in 2023, with the first researchers moving in 2026.
Further information:
https://www.uni-due.de/activesites/https://www.uni-due.de/cenide/news-detail.php?id=active-sites-neue-methoden-fuer-spitzenforschung
- IRTG 2D-Mature: Scalable 2D-Materials Architectures
15th July 2022,
International DFG Research Training Group starts in October. Read original article
The 2D-Mature is inspired by the Nobel Prize-winning discovery of graphene, a two-dimensional carbon crystal just one atom thick. The superior and often unique properties of graphene and related 2D materials open up seemingly endless possibilities for industry and could revolutionize a wide range of electronic applications.
2D-MATURE will address these challenges with cutting-edge research on 2D nanomaterials and the training of the next generation of scientists and engineers who will be able to use these materials in a wide range of applications.
The research and training will be carried out by a team of principal investigators (Pis) representing the Departments of electrical, mechanical and chemical engineering as well as physics and chemistry at the University of Duisburg-Essen (Germany) and the University of Waterloo (Canada). Both institutions are home to leading international nanotechnology research centers with a long tradition of connecting fundamental science and engineering science. The team is complemented by a PI from RWTH Aachen University (Germany).
The main goal of 2D-MATURE is to provide a comprehensive overview of scalable routes for synthesizing and processing 2D material units to develop a deep understanding of emerging functionality. The goal is to enable and test their application in practical demonstration devices such as super-capacitors, batteries, light sensors and light-emitting devices to bring new 2D materials from the lab to market.
- Green Light for Hydrogen Center
2nd June 2022,
Proof-of-concept successful. Read original article
Ideas relating to hydrogen as an energy carrier can be implemented quickly thanks to the existing H2 infrastructure at the Duisburg site. TrHy supports all steps up to the application of the new technology. © ZBT GmbHThe Innovation and Technology Center for Hydrogen (ITZ H2) with its four locations nationwide is possible. This was the result of an audit by the German Federal Ministry for Digital and Transport (BMDV). The hydrogen and fuel cell center (ZBT) of the UDE is coordinating the establishment in Duisburg, in which companies and research institutions from all over North Rhine-Westphalia are participating. Once the federal funding guidelines are in place, the sites hope to receive approval before the end of the year.
The center in Duisburg is now called “TrHy” (pronounced like the English “try”). The name in full: TrHy - The Hydrogen Proving Area. The main focus here is on compressed hydrogen applications with high energy requirements in heavy-duty road and rail transport and in inland shipping. TrHy will be officially established as a company in the summer. Initially, ZBT will be the lead partner, but in the medium term it sees itself as one of many partners.
The TrHy team provides advice and support to potential customers to help them get started with or further develop hydrogen technologies for mobility applications. Standardization, norming, and subsequent certification for the safe development of the hydrogen economy are also part of TrHy's tasks. The geographical center of the network is the 18,000 square meter hall on the site of Hüttenwerke Krupp Mannesmann (HKM).
The other locations of the ITZ network in Germany are Chemnitz, Pfeffenhausen in Bavaria, as well as the North Facility including Hamburg, Bremen/Bremerhaven and Stade. All centers set different priorities that complement each other.
Dr. Volker Wissing, Federal Minister for Digital and Transport, on the positive outcome of the proof-of-concept study: “This means we can now get down to implementation. The BMDV has earmarked up to 290 million euros as start-up funding for the total of four sites, and the federal states want to give the centers additional support.”
According to the Ministry of Economics, NRW could save a quarter of its current CO2 emissions in the future by using hydrogen and create up to 130,000 sustainable jobs.
https://www.uni-due.de/2022-05-30-wasserstoffzentrum-trhy-kommt
- Targeted Design of New Catalyst Materials
27th May 2022,
Extension for SFB/TRR 247. Read original article
View of the center of a synthesis reactor in which nanoparticles are created and studied within a spray flame - for example, for the development of new catalyst materials. The probe projecting into the flame for sampling withstands temperatures of up to 2,600°C. © UDE/Samer SuleimanAlmost all everyday objects come into contact with at least one catalyst during their production in order to make their production cheaper, more environmentally friendly or even possible in the first place. The goal of the SFB/TRR 247 "Heterogeneous Oxidation Catalysis in the Liquid Phase" is to develop inexpensive, highly active and selective catalysts at the atomic level. Following its successful first funding phase from the DFG, it is being extended for a further four years and funded with 12.3 million euros.
The researchers are now focusing on identifying active centers of the materials and understanding reaction mechanisms in detail. The Ruhr University Bochum (RUB) is now the spokesperson, with Prof. Dr. Stephan Schulz from the Institute of Inorganic Chemistry at the University of Duisburg-Essen (UDE) as co-spokesperson.
Until now, new catalysts have often been discovered by trial and error. Instead, the SFB/TRR 247 aims to develop a rational design of cost-effective as well as highly active and selective catalysts based on mixed metal oxides for selective oxidation processes in the liquid phase. "An important aspect here is also to replace rare precious metals with readily available and less expensive materials," explains spokesperson Kristina Tschulik. To achieve this, the highly complex chemical processes that take place - in the case of heterogeneous catalysis, where the catalyst is a solid - at the catalyst surface must be better understood.
Twenty research groups from the Ruhr-Universität Bochum, the University of Duisburg-Essen, the Christian-Albrechts-Universität zu Kiel, the Max Planck Institute for Chemical Energy Conversion, the Max Planck Institute for Coal Research, both in Mülheim/Ruhr, and the Fritz Haber Institute of the Max Planck Society, Berlin, have joined forces in the alliance. - Teaching from Practice
16th May 2022,
Honorary Professorship for Christof Asbach. Read original article
The photo shows from left to right Prof. Dr. Heinz Fissan, Prof. Dr. Christof Asbach, Prof. Dr. Dieter Schramm (Dean of the Faculty of Engineering), Prof. Dr. Dieter Bathen (Scientific Director of IUTA). © privatWith his festive opening lecture on May 13, Dr.-Ing. Christof Asbach, Head of Department at IUTA, now holds the title of Honorary Professor. He was awarded the title by Prof. Dr.-Ing. Dieter Schramm, Dean of the Faculty of Engineering at the University of Duisburg-Essen (UDE). Asbach is president of the Society for Aerosol Research and an internationally recognized expert in this field.
In about 100 publications, he has dealt with dust exposure at workplaces, particle contamination in the semiconductor industry and particle formation in automotive wheel brakes, among other topics. And during the Corona pandemic, he was on television and radio stations, regional and national newspapers explaining how aerogenic viruses are transmitted.
At the UDE, Asbach has been teaching the Environmental Measurement Technology lecture in the master's programs in mechanical engineering, industrial engineering and NanoEngineering since the summer semester of 2013.
Asbach studied electrical engineering at the University of Duisburg-Essen and earned his doctorate under Prof. Fissan. After nearly two years of post-doctoral research at the University of Minnesota, he became a research associate at IUTA in 2006. Since 2013, he has headed the Filtration & Aerosol Research Department there.
* IUTA is a research institute in the field of energy and environmental technology and forms the bridge between basic research and industrial application.
- DFG Funds Two New Research Training Groups
9th May 2022,
Success for the UDE. Read original article
Two-dimensional materials in wafer size (diameter wafer: 5 cm), produced with a scalable gas phase process. © UDE, Henrik MyjaMaterials science and medicine at the UDE can further expand their research. The German Research Foundation (DFG) is funding two new research training groups with a total of around 14 million euros for the next five years. The research subjects are the properties and production of two-dimensional materials and the effectiveness of radiation treatment for cancer.
Two-dimensional materials are extremely thin and in some cases consist of only a single layer of atoms. They are particularly interesting because they have unique electrical and optical properties and can be rolled, folded or stretched due to their high mechanical stability. The international research training group 2D-MATURE* (GRK 2803) at the Faculty of Engineering with participation from the Faculty of Physics will address two questions: How can two-dimensional materials be produced in large quantities and how do they behave when combined with other materials in such a way that they can be used in products?
The goal is to develop new methods and processes to enable industrial-scale applications, for example in light-emitting diodes or batteries. The college is headed by Prof. Gerd Bacher and is funded with around 7 million euros. The doctoral students conducting research at the Center for Nanointegration Duisburg-Essen (CENIDE) will collaborate with Canadian colleagues at the Waterloo Institute of Nanotechnology (WIN) at the University of Waterloo.
* "Scalable 2D Material Architectures (2-D MATURE). Synthesis and processing, characterization and functionality, implementation and demonstration."
https://www.uni-due.de/2022-05-09-grk-in-medizin-und-materialwissenschaft-gefoerdert
- New Directions for the ‘Energiewende’
2nd May 2022,
Seminar on Materials and Energy. Read original article
© WE-HeraeusFrom materials in science fiction, research and the circular economy – the WE-Heraeus seminar "Materials and Energy – New Directions for the ‘Energiewende’" aims to stimulate new ways of thinking and research in the field of energy and materials research. Therefore, five sessions with speakers from Germany, Denmark and Canada, including CENIDE PI Prof. Rossitza Pentcheva, will take place at the Physikzentrum Bad Honnef from October 23 to 27. Deadline for registration is August 28.
The topics of "energy" and "materials" are interconnected in many ways from basic research to real-world applications. However, analyzing their intricate relationship as an energy-material nexus is new. This is exactly what the seminar will focus on. The five sessions will focus on the following:
Session 1: Fundamental Physics - Concepts that Define Demands for Materials
Session 2: The Materials Space
Session 3: The Materials' Function in Energy Technologies
Session 4: Old Materials - New Perspectives
Session 5: The Materials' "Economy
The organizers of the 773. WE-Heraeus Seminar are Prof. Jürgen Janek from Justus-Liebig-Universität Gießen and CENIDE PI Prof. Christof Schulz.
Organizing scientific seminars is the oldest and most prominent funding activity of the Wilhelm Heinrich Heraeus and Else Heraeus Foundation. The program has been in existence since 1975 and has brought together over 40,000 participants to date. Heraeus seminars often bring together experts with doctoral students and postdocs. Therefore, contributions from young researchers are especially welcome. For all participants it is required to apply for admittance. Complimentary on-site and full-board accommodation is provided by the Wilhelm and Else Heraeus Foundation, and there is no conference fee.
Further information and registration:
www.we-heraeus-stiftung.de/veranstaltungen/materials-and-energy-new-directions-for-the-energy transition/ - Science Council Recommends Research Building on Catalysis
29th April 2022,
New Methods for Different Disciplines. Read original article
© Carpus+Partner AGMilestone decision for basic research at the University of Duisburg-Essen (UDE): The Science Council has classified the planned ACTIVE SITES research building as worthy of funding. The project will thus be realised - subject to the final decision of the Joint Science Conference (GWK). The federal government and the state of North Rhine-Westphalia will each bear half of the costs for construction and equipment, which amount to 69 million Euros. With ACTIVE SITES, the UDE will have a centre of international acclaim at which so-called active sites will be researched.
The active site is the decisive point of a catalyst or protein where something new is created from one or more starting materials in a chemical reaction. Catalysts are essential for natural chemical and biological processes, but also play a key role in many technical areas from water purification to energy conversion. A better understanding can contribute to finding answers to currently pressing questions, such as how it is possible to remove CO2 from the atmosphere and convert it into energy sources. The goal is therefore not only to gain new insights into how exactly these ultrafast processes work, but also how they can be influenced.
Science Minister Isabel Pfeiffer-Poensgen says: "The Science Council's funding recommendation is impressive proof of the high scientific potential of the research building ACTIVES SITES. It will help to further strengthen the research into materials and substance development in the field of energy technology and biomedicine at the University of Duisburg-Essen. At the same time, the Research Alliance Ruhr formed by the three Ruhr universities will benefit from the new research building and thus increase the international visibility of the university and the entire Ruhr region as a major science hub."
Unique approach to developing new methods
In the new research building, scientists from different disciplines such as chemistry, physics, biology and engineering will work together. The concept of working across disciplines as well as across substances is the first of its kind. Rector Professor Barbara Albert emphasises: "This is an important step and a great success not only for the UDE. New methods can now be developed that use knowledge from different disciplines to explore large, overarching themes and questions." The Research Alliance Ruhr will also benefit from the new building: "In particular, the Research Centres 'One Health', 'Chemical Sciences and Sustainability' and 'Future Energy Materials and Systems' will be able to use the knowledge gained for their own research," Albert continues.
The scientists' approach is special: "We want to investigate actives sites in their natural environment during the chemical, biological and physical processes" says the chemical engineer and deputy spokesperson of ACTIVE SITES, Professor Corina Andronescu. "So far, active sites are mostly analysed either in artificial environments or only indirectly by comparing them before and after the reaction. But this is not enough to fully understand how they work."
The expectation is that the scientists from the different disciplines will benefit directly from each other: "We assume that a set of methods developed, for example, by a biologist in the analysis of a cell in a cell cluster can also be applied by an engineer in the analysis of a single particle in a mass of catalyst particles," Andronescu elaborates.
Architecture should stimulate interdisciplinary exchange
The new building will reflect the interdisciplinary approach. The plans call for many open work spaces and shared laboratories. These are intended to encourage exchange and can be flexibly adapted to the needs of different research groups. The building will have a total floor space of about 4,800 square metres and offers 125 workplaces. It is to be built on the site Am Thurmfeld, which is adjacent to the north of the existing campus in Essen. "I am particularly pleased that we are the sole developer and can realise this project on our own land," says Chancellor Jens Andreas Meinen. Construction is scheduled to begin in 2023, with the first researchers moving in in 2026.
https://www.uni-due.de/2022-04-29-wissenschaftsrat-empfiehlt-forschungsbau-zu-katalyse
- Passion for Interfaces and Music
11th April 2022,
Dr. Christopher Stein in Portrait . Read original article
© Bettina Engel-AlbustinChemistry or physics? Dr. Christopher Stein had a hard time deciding which subject to study. Today, the theorist combines both: As a returnee to NRW, the future professor in the Faculty of Physics studies interface and surface phenomena and proves to his students how exciting fundamental research can be.
In the two-part interview, he talks about his stays in Switzerland and the USA, what makes good lecturing for him, and why the UDE was the best choice for his research.
- From Platinum Alloys to Complex Solutions
4th April 2022,
Electrocatalysts for the Oxygen Reduction Reaction. Read original article
Challenges in the electrochemical evaluation of complex alloys. © Martínez-Hincapié, Čolić
Boosting reaction kinetics to improve storage and conversion of renewable energy: One of the most researched is the oxygen reduction reaction, which is the bottleneck for the development of fuel cell technology. In a new review article, Center for Nanointegration Duisburg-Essen (CENIDE) member Dr. Viktor Čolić discusses recent progress in research and existing challenges in the electrochemical evaluation of alloy materials – as catalysts for the reaction.
Of particular interest for discussion are complex alloy materials, that is, alloys with multiple principal constituents (MPCAs). They have emerged as a material that could potentially replace platinum and platinum-based materials – electrode materials that are very expensive and scarce, and therefore not widely applicable. Because this new type of material exhibits a wide variety of active sites, it may enable that the optimal binding site on the catalyst surface to be determined experimentally.
Čolić’s research group "Electrochemistry for Energy Conversion" at the Max Planck Institute for Chemical Energy Conversion (MPI-CEC) was jointly established with UDE in 2019 and the labs are located in the NanoEnergieTechnikZentrum (NETZ) in Duisburg. The group primarily aims to use electrochemical methods in conjunction with surface science and other instrumental analytical techniques to investigate the relationships between surface and electrolyte properties and electrocatalytic activity. The focus is on reactions of interest for energy conversion, storage, and utilization.
Original publication:
Martínez-Hincapié, R.; Čolić, V. Electrocatalysts for the Oxygen Reduction Reaction: From Bimetallic Platinum Alloys to Complex Solid Solutions. ChemEngineering 2022, 6, 19. https://doi.org/10.3390/chemengineering6010019 - Heat as Energy Storage
4th April 2022,
DFG Funds Research on Carnot Battery . Read original article
© Val_Thoerner, stock.adobe.comWind farms, photovoltaic systems and tidal power plants supply electricity sustainably – but not consistently. The central, yet still unsolved problem is therefore how to store energy that is not currently needed. One promising option is Carnot batteries, which store energy in the form of heat. The German Research Foundation (DFG) is now establishing a new Priority Program (SPP) under the leadership of the University of Duisburg-Essen (UDE): The team is taking a unique approach: starting with market needs, it will design optimal batteries and then determine step by step down to the molecular level how they can be realized.
A Carnot battery stores energy as heat in low-cost materials such as water, stone or in the form of molten salts. When needed, this is converted back into electrical energy, i.e. electricity, by steam turbines, for example. Although the principle has been known for a long time, there is as yet hardly any reliable data on efficiencies, costs or even the concrete potential for application in energy storage.
This gap is what the SPP "Carnot batteries: Inverse Design from Market to Molecule" with its fundamentally new approach of "top-down methodology" not only to close this gap, but to overcome it right away with the best possible end result.
"Together with economists, we analyze what is actually needed and look for the physical-technical possibilities and limits," affirms Materials Chain member Prof. Dr. Burak Atakan, head of the "Thermodynamics" department at the UDE Institute of Combustion and Gas Dynamics and spokesperson for the newly established SPP 2403. "Then we go into more and more detail in steps, determine the best possible mode of operation, suitable circuits, suitable substances and their ideal combinations - in order to develop the optimal Carnot battery in the end." The aim is to verify whether storage efficiencies of over 70 percent and costs below €100/kWh can actually be achieved.
The coordination team from the universities of Bochum, Kassel, Stuttgart and the UDE is well aware of the risks involved: "Our approach is risky because the target parameters could turn out to be unattainable," says Atakan. "And yet it is groundbreaking because it establishes for the first time a cross-disciplinary, inverse method that starts from market requirements - and not from what has been possible so far under laboratory conditions."
The German Research Foundation (DFG) will fund SPP 2403 with approximately 2.5 million euros annually starting in 2023.
https://www.uni-due.de/2022-04-04-spp-zu-carnot-batterien-an-ude
- Success for the UDE
4th April 2022,
State Promotes Networks . Read original article
Scientists in a laboratory at the Terahertz Integration Center of the UDE. © UDE/ZHOStarting in August, the NRW state government is funding five outstanding research networks with more than 81 million euros to strengthen them in the long term. The topics are future-oriented brain research, artificial intelligence, information technology, cancer treatment and particle physics. The University of Duisburg-Essen (UDE) is involved in two of the funded networks: terahertz.NRW and CANTAR will receive up to 19.4 million euros over the next four years to further develop their ideas.
terahertz.NRW
Three universities and two Fraunhofer institutes belong to this network, most of which have already been working together successfully since 2017. They want to tap the potential of miniaturized electronic and photonic THz circuits, in which the network partners are among the global leaders. For example, a pen for diagnosing skin cancer, a sensor integrated into a cell phone for analyzing viruses, bacteria and gases are conceivable - and much more.The contact person at the UDE is Professor Dr. Thomas Kaiser from the Institute for Digital Signal Processing. The network is headed by the Fraunhofer Institute for High Frequency Physics and Radar Techniques, and other partners include Duisburg's Fraunhofer Institute for Microelectronic Circuits and Systems and the universities of Bochum and Wuppertal.
CANTAR (CANcer TARgeting)
This network also builds on established collaborations - in this case between researchers from chemistry, biology and medicine. It aims to identify specific pathways driving cancer and to find out how cancer can "escape" the immune system. To this end, substances are to be developed that act specifically on tumor cells or intervene in metabolic processes and spare normal tissue.Prof. Dr. Christian Reinhardt, Medical Faculty of the UDE/Clinic for Hematology and Stem Cell Transplantation of the University Hospital, is leading the research for the UDE. The University of Cologne has overall leadership; also involved are the Universities of Dortmund, Düsseldorf and Bonn, the Max Planck Institute for Molecular Physiology, the German Center for Neurodegenerative Diseases (DZNE) and the TH Aachen.
https://www.uni-due.de/2022-04-01-foerdererfolg-fuer-die-UDE
- Growing quantum dots in a regular arrangement
28th March 2022,
With the manufacturing process used so far, it was difficult to control the density of the structures. Now, researchers will be able to create a chessboard pattern. It is a step towards application.. Read original article
The researchers use this experimental setup to analyse the quality of the quantum dots. The quantum dots are excited with green laser light and respond with the emission of infrared light. © İsmail BölükbaşıQuantum dots could one day constitute the basic information units of quantum computers. In collaboration with colleagues from Copenhagen and Basel, researchers from Ruhr-Universität Bochum (RUB) and the Technical University of Munich (TUM) have decisively improved the manufacturing process for these tiny semiconductor structures. The quantum dots are generated on a wafer: a thin semiconductor crystal disc. To date, the density of such structures on the wafer has been difficult to control. Now, researchers can create specific arrangements in a targeted manner – an important step towards an applicable component that would be expected to have a large number of quantum dots.
The team published its findings on 28 March 2022 in the journal Nature Communications. The study was conducted by a group headed by Nikolai Bart, Professor Andreas Wieck and Dr. Arne Ludwig from the RUB Chair of Applied Solid State Physics in cooperation with the team led by Christian Dangel and Professor Jonathan Finley from the TUM Semiconductor Nanostructures and Quantum Systems research group and colleagues from the Universities of Copenhagen and Basel.
Like mushrooms in the forest
Quantum dots are narrowly defined areas in a semiconductor in which, for example, a single electron can be confined. This can be manipulated from the outside, for example with light, so that information can be stored in the quantum dot. The researchers from Bochum are experts in the production of quantum dots. They create the structures on a wafer made of a semiconductor material that is about the size of a beer coaster. The quantum dots have a diameter of only about 30 nanometres.
“Our quantum dots used to grow like mushrooms in the forest,” as Andreas Wieck describes the initial situation. “We knew that they would emerge somewhere on the wafer, but not exactly where.” The researchers then chose a suitable mushroom in the forest for their experiments with the quantum dots.
Preliminary cultivation experiments
In a number of preliminary experiments, the team had already tried to influence the growth of the quantum dots on the wafer. The physicists had irradiated the wafer at individual points with focused ions, thus creating defects in the semiconductor crystal lattice. Acting like condensation nuclei, these defects provoked the growth of quantum dots. “But just as cultivated mushrooms taste somewhat bland while forest mushrooms taste great, the quantum dots created in this way were not as high quality as the naturally grown quantum dots,” illustrates Andreas Wieck. They did not radiate light as perfectly.
Therefore, the team proceeded with the naturally grown quantum dots. For the experiments, the beer coaster-sized wafer was cut into millimetre-small rectangles. They couldn’t analyse the whole wafer at once, because the vacuum chamber of the RUB apparatus simply wasn’t big enough. However, the researchers observed that some wafer rectangles contained many quantum dots, while others contained few. “At first, we didn’t notice any system behind it,” Andreas Wieck recalls – because the researchers never saw the whole picture.
High-quality quantum dots
To explore the question in depth, the Bochum team cooperated with their colleagues at the TUM, who had a measuring device with a larger sample chamber at their disposal at an early stage. During these analyses, the group found that there was a strange distribution of areas with high and low quantum dot densities on the wafer. “The structures were strongly reminiscent of a moiré pattern that often occurs in digital images. I soon hit on the idea that it must actually be a concentric pattern, i.e. rings, and that these could be seen in correlation to our crystal growth,” explains Arne Ludwig. Measurements with higher resolution indeed showed that the density of quantum dots was distributed concentrically. Subsequently, the researchers confirmed that this arrangement was due to the manufacturing process.
In the first step, the wafer is coated with additional atomic layers. Due to the geometry of the coating system, this creates ring-shaped structures that have a complete atomic layer, i.e. where no atom is missing at any point in the layer. Between the rings, similarly wide areas are formed that lack a complete atomic layer and thus have a rougher surface because individual atoms are missing. This has consequences for the growth of the quantum dots. “To stick with the image: rather than on a concreted surface, mushrooms prefer to grow on forest floor, i.e. on the rough spots on the wafer,” says Andreas Wieck.
The researchers optimised the coating process so that the rough areas appeared at regular intervals – of less than a millimetre – on the wafer and that the rings intersected. This resulted in an almost chessboard-like pattern with quantum dots of high quality, as demonstrated by the researchers from Basel and Copenhagen.
- Award for Chemist Dr. Kai Exner
21st March 2022,
Independent field of research established. Read original article
© Negro Elkhan, stock.adobe.comIt is the highest honor for young researchers in chemistry: University of Duisburg-Essen (UDE) Professor Dr. Kai S. Exner will receive this year's ADUC* Award on March 21. The jury was particularly impressed by the quality and number of his scientific publications in high-ranking journals.
Exner can already look back on more than 50 published articles in renowned journals. The 34-year-old's research focuses on theoretical studies of electrode materials for batteries, electrolyzers or fuel cells. His calculations and theoretical models help avoid dead ends in the development of new materials and focus on the most promising candidates.
Exner chose UDE within the NRW Returner Program and was also awarded a junior professorship in Theoretical Inorganic Chemistry in June 2021, funded by the Federal-State Program for the Promotion of Young Scientists (WISNA). He is also already well networked: he is a member of both the Center for Nanointegration (CENIDE) and the Collaborative Research Center 247 "Heterogeneous Oxidation Catalysis in the Liquid Phase" and also conducts research in the RESOLV (Ruhr Explores Solvation) Cluster of Excellence.
The theoretical electrochemist has already received several awards, including the Ewald Wicke Prize of the German Bunsen Society for Physical Chemistry, the Joachim Walter Schultze Prize of the Association of Electrochemical Research Institutions, and the Jochen Block Prize of the German Catalysis Society.
*The Association of German University Professors of Chemistry promotes research in chemistry as well as young scientists. Each year, the ADUC honors up to three young scientists who have succeeded in establishing an independent field of research.
https://www.uni-due.de/2022-03-15-aduc-preis-fuer-chemiker-exner
- Chemical Industry Fund
21st March 2022,
Kekulé Fellowship. Read original article
© private
Helene Giesler from the Schlücker group at the University of Duisburg-Essen (UDE) has successfully obtained a two-year Kekulé fellowship for her PhD. For this purpose, Giesler will work on photothermal precision immunotherapy with molecularly functionalized gold nanoparticles over the next three years.
The Kekulé Fellowship from the Fonds der Chemischen Industrie (FCI) funds PhD candidates in Germany working in chemistry or chemistry-related life science research. The entire research group and the Faculty of Chemistry wish Giesler every success with her PhD.
- Detection of Spin Crossover in Cobalt Complexes
21st March 2022,
AG Wende in Applied Chemistry . Read original article
Current-voltage curves (a) of the molecules in the ground state L (b) and the excited state H (c). © AG WendeIn a collaboration led by Richard Berndt (CAU Kiel) and Manuel Gruber (University of Duisburg-Essen), scanning tunneling microscopy was used to detect spin crossovers in complex cobalt tetramers on a silver surface.
So-called spin crossover (SCO) molecules are promising candidates for the future of data storage. They have a much higher data density than is feasible today, with a large fraction of the currently known complexes being based on iron so far. The contribution of the research group of Center for Nanointegration Duisburg-Essen (CENIDE) board member Prof. Dr. Heiko Wende was the element-specific analysis of such complexes by photoemission spectroscopy.
Original publication: S. Johannsen, S. Ossinger, J. Grunwald, A. Herman, H. Wende, F. Tuczek, M. Gruber, and R. Berndt, Angew. Chem. Int. Ed. (accepted January 2022), https://doi.org/10.1002/anie.202115892
- Support for Researchers
21st March 2022,
Solidarity with Ukraine . Read original article
© Sylwia Bartyzel, Unsplash
With great concern and horror, CENIDE is also following the war against Ukraine. They too want to think along to the best of their ability and help people in need. Therefore, CENIDE offers various forms of support in the field of nano- and material sciences for researchers from Ukraine who have to leave their home country.
If you yourself are interested in doing research at CENIDE or you know of researchers from Ukraine who need support, contact them at cenide@uni-due.de.
UDE Welcome Service: https://www.uni-due.de/welcome-service/en/index.php
UDE Info for Refugees: https://www.uni-due.de/en/refugees.php
CRC/TRR 247: https://www.uni-due.de/imperia/md/images/sfbtrr247/ukrainian_research_fellowships.pdf - With Research for the Future
10th March 2022,
"Duisburg ist echt". Read original article
© Duisburg ist echt
What is Duisburg? Landschaftspark and Küppersmühle, Sechs-Seen-Platte and Skatepark by the Rhine, MSV Stadium and the multitude of people - the DUISBURG IST ECHT campaign puts the spotlight on what makes Duisburg special. Also included are shots from the Nanoenergie Technikzentrum (NETZ) and thoughts from Center for Nanointegration Duisburg-Essen (CENIDE) scientist Dr. Nicolas Wöhrl on the research landscape in the Ruhr region.
The encounter was captured in an article with a short video.
DUISBURG IST ECHT is intended to present the city in a new way. The project shows the excursion, sports and cultural offerings, the green spaces, the university and many other places and people that make Duisburg what it is.
https://www.duisburgistecht.de/
https://www.duisburgistecht.de/magazin/der-kuchenteig-fur-die-brennstoffzelle-von-morgen - 20 Million for Quantum Computing
10th March 2022,
NRW-Wide Network . Read original article
Cryostat of the quantum computer at Forschungszentrum Jülich. © FZ Jülich/Sascha KreklauIt is about nothing less than solutions for the challenges of our time: More than a dozen research institutions in NRW have joined forces to form the new quantum computing network "EIN Quantum NRW", including the University of Duisburg-Essen (UDE). Minister President Hendrik Wüst, Minister of Science Isabel Pfeiffer-Poensgen and Minister of Economics Prof. Dr. Andreas Pinkwart informed about this today together with partners from science and industry.
"We are proud that North Rhine-Westphalia is a European hotspot for quantum computing," said Minister President Hendrik Wüst. EIN Quantum NRW will receive up to 20 million euros over an initial funding period of five years. 7.5 million euros will be contributed by the research institutions themselves through cooperation with industry. The state government will top up this contribution with up to 12.5 million euros by 2026. "Quantum computing is a global innovation. The new competence network links science with the great economic power in our state. No other region in Germany has such extensive expertise, infrastructure and networking as North Rhine-Westphalia. We are proud that our state has become a European hotspot for quantum computing. The state government will further expand this strong position as part of its Digital Strategy 2.0 and thus further promote the strategic networking of science and industry."
Quantum technologies are expected to help provide new answers to major questions and challenges: for example, for complex interrelationships of climate change, the protection of the environment, better traffic flows or tap-proof communication through quantum encryption, for example, to reduce risks to critical infrastructures through cyber attacks. Already today, numerous technical achievements can be traced back to findings in quantum physics. Examples range from photovoltaic cells to laser and medical technology - such as magnetic resonance imaging - to modern computers and the Internet.
In addition to the UDE, the network's founding partners include the universities of Aachen, Bochum, Bonn, Dortmund, Düsseldorf, Cologne, Münster, Paderborn, Siegen, as well as the German Aerospace Center (DLR), the Jülich Research Center, and the Fraunhofer-Gesellschaft. The coordination is currently carried out by the Research Center Jülich and the University of Siegen.
https://www.fz-juelich.de/portal/EN/Press/PressReleases/2022/2022-03-09-qsolid/_node.html
- When the Microscope Goes Online
10th March 2022,
Digital Equipment for Nano School Lab . Read original article
Electron microscope image of a diatom only a few micrometers in size from the NanoSchoolLab. © UDE/NanoSchoolLabWhat the electron microscope shows looks like a drainage sieve - but it's actually a diatom just a few micrometers in size. Many young people have already had aha moments like this in the NanoSchoolLab at the University of Duisburg-Essen (UDE). Now it is receiving around 41,000 euros for digital equipment from the European Regional Development Fund (ERDF).
Among other things, desktop computers, laptops and a video conferencing system are on the shopping list of Dr. Kirsten Dunkhorst, the head of the NanoSchoolLab. Connected to microscopes that young people would otherwise only get to know during their studies, modern learning stations are to be created that will allow students to see the fascinating images from the nanoskomos or participate in the measurements even from a distance. The improved equipment will also help young people practice using the instruments and learn about evaluation software and systems for 3D models.
"With the new infrastructure, we can strengthen the digital skills of young people and their teachers, while at the same time getting students excited about STEM subjects," Dunkhorst explains. "In this way, we can help close the gaps revealed by the pandemic."
Within the "NanoSchoolLab goes digital" project, a subject didactic concept is being developed to digitally expand and consolidate the structures already established in the pandemic. There will be both stationary and mobile solutions, which can thus be used at different locations.
The funding comes from the "zdi-REACT-EU" program of the state of North Rhine-Westphalia, which supports the development and expansion of the digital infrastructure of extracurricular places of learning.
The NanoSchoolLab at UDE was founded in 2009 by the Faculties of Engineering and Physics and the NanoEngineering program with the support of the Center for Nanointegration Duisburg-Essen (CENIDE) as a zdi school lab. It is an extracurricular place of learning specializing in nanotechnology that introduces students to the principles of scientific and technical research.
https://www.uni-due.de/2022-03-08-digitale-ausstattung-fuer-nanoschullabor
- A Sieve for Molecules
7th March 2022,
Application of 2-Dimensonal Silica.
The researchers apply the 2D silica layer - which is not visible to the naked eye - to a gold surface. © RUB, KramerResearchers from Bielefeld, Bochum and Yale have succeeded in producing a layer of two-dimensional silicon dioxide. This contains natural pores and can therefore be used like a sieve for molecules and ions. Scientists have been looking for such materials for some time, because they could help desalinate seawater or be used in new types of fuel cells. The team describes the fabrication process in the journal Nano Letters, published online Jan. 19, 2022. The teams led by Dr. Petr Dementyev of Bielefeld University, Prof. Dr. Anjana Devi of RUB and Prof. Dr. Eric Altman of Yale University collaborated on the work.
Natural openings in the crystal lattice
When two-dimensional materials are pierced with high precision, they can be used to screen out specific ions or molecules. Researchers have repeatedly tried to use graphene, a material made of carbon atoms, for this purpose. Since it has no natural pores, they have to be inserted artificially. But it is difficult to create holes of a defined size in graphene without permanently damaging the material, which breaks easily. This is because it loses too much stability due to the perforation. Consequently, an alternative had to be found. In the current work, the research team took advantage of the fact that the crystal lattice of two-dimensional silicon dioxide naturally has openings. They showed that these openings can be used to separate certain gases from one another.
Fabrication problematic
2D silicon dioxide has been known since 2010. However, its production was very expensive and only possible on a small scale. The researchers from Bochum, Bielefeld and Yale brought together expertise from materials chemistry, chemical engineering and chemical physics to devise a new manufacturing process. They used what is known as atomic layer deposition to deposit a single layer of silicon dioxide on a gold surface.
"We expect our results to be important for materials science worldwide," sums up Anjana Devi from the Bochum-based Inorganic Materials Chemistry group. "Such 2D membranes could be at the forefront of helping sustainable development, for example in the field of energy conversion or storage."
- Limits of Measurability of Quantum Jumps Pushed Back
28th February 2022,
New Publication in Physical Review Letters . Read original article
© SFB 1242Correct counting determines our modern life – be it the bits in a computer with their two states, the number of positive coronatests, or generally any system that has countable events. But the faster counting is done and the smaller the signals involved are, the more likely data can get lost in the noise. Theoretical physicist Eric Kleinherbers of Collaborative Research Center (SFB) 1242 and Center for Nanointegration Duisburg-Essen (CENIDE) now developed a new tool with colleagues inside that sheds more light on such data.
Counting statistics are particularly important in the quantum world. Modern measuring instruments are so sensitive that they can detect single quantum jumps. Limiting factors are the time resolution of the detector, the background noise, and the observation time. In addition, detection errors distort the measured information, leading to no or incorrect conclusions about the underlying quantum dynamics.
For their work, the researchers used so-called self-assembled quantum dots, which have similar properties to individual atoms, and employed a trick. The quantum dot is excited with a laser and radiates back light particles (photons) as long as it is "empty." If an additional electron enters the quantum dot, the light current breaks off. Thus, the photons can be used to record the electron occupation in real time, which can then be statistically analyzed.
To test how robust the new evaluation algorithm is, data was intentionally deleted from the original data set, simulating a faulty measurement. "These were typical experimental errors: signals that are too fast for the detector and are therefore "missed" or a spike in the noise that fakes a signal" explains Eric Kleinherbers, lead author of the study. By comparing the original readings with the erroneous data, the researchers were able to demonstrate that the new method of analysis is much more error-tolerant than the standard methods of statistical analysis used previously. This makes the actual behavior of electrons and photons more visible, shedding light on the quantum world. "It's a bit like trying to put a screw in the wall with an improper screwdriver until now," Kleinherbers explains. "It works, but it's not pretty. Now we have the right tool for analyzing the data."
Counting statistics are everywhere: in the evaluation of nerve signals as well as in radioactive decay, in microelectronics as well as in magnetism. While experimental physicists are constantly coming up with new measurement techniques and experiments, theorists are also pushing the boundaries of feasibility with new evaluation methods. The developed method is not only interesting for new measurement results – existing data can now also be examined more closely, as Kleinherbers says. "We are in close exchange with colleagues who now want to see what else might be hidden in their data."
The results were published March 23, 2022, in the journal Physical Review Letters: www.doi.org/10.1103/PhysRevLett.128.087701
- Making the cement industry climate-neutral
17th February 2022,
In a new project, researchers are looking for ways to convert the climate gas CO2 into feedstock for industry..
A new project is looking at how to make the cement industry carbon-neutral.The German Federal Ministry of Economics and Climate Protection is funding the project as part of the "Application-oriented non-nuclear R&D in the German government's 7th energy research program" measure in the area of "Technologies for the CO2 circular economy."
The concrete solution path taken by Fraunhofer UMSICHT, Leuchtstoffwerk Breitungen, Phoenix Zementwerke Krogbeumker and RUB is called Power-to-Chemicals. Renewable energies such as wind power are used to convert CO2 and water into carbon monoxide and hydrogen via electrolysis. Mixtures of these two substances - known as synthesis gases - are then used to produce the desired chemical products by means of further catalytic conversion processes.
Wanted: robust and poisoning-resistant catalysts.
The biggest hurdle: CO2 released from cement plants must be extensively purified and conditioned for further processing. "For example, catalyst poisons, dust and other impurities must be removed," says Dr. Kai junge Puring of Fraunhofer UMSICHT. "This is a challenge both technically and economically."
The project partners' goal is therefore to create a new process route that can also be adapted by other cement plants. "Ideally, we want to use the CO2 waste gas streams directly to produce the synthesis gases with the help of renewable energies and waste heat sources - without any complex upstream purification and conditioning," says Dr. Anne Schmidt from Leuchtstoffwerk Breitungen. "For this, we need robust and poisoning-resistant catalysts that are both stable over the long term and economical."
Im Fokus der Forschenden stehen daher sulfid-, nitrid- und phosphidbasierte Materialien. They are very stable to typical catalyst poisons such as sulfur, but have not yet been systematically investigated as potential catalysts for syngas production from CO2 or for subsequent syngas conversion to olefins and higher alcohols. "We want to change that and are aiming to set up a lab-scale process in the next 36 months," explains Prof. Dr. Ulf-Peter Apfel from RUB.
System integration through multi-criteria evaluation methods
The process is followed by system integration: how can the finished power-to-chemicals concept be integrated into existing cement plant structures? "To answer that, we have to identify, model and evaluate specific site conditions - i.e. infrastructure aspects, surrounding wind and photovoltaic plants or potential customers for the target products," says Dr. Sebastian Stießel from Fraunhofer UMSICHT.
"In addition, we need to develop new business models for marketing CO-based products, which we extract from the exhaust gases, and bring them into line with existing value chains," adds Marcel Krogbeumker of Phoenix. To this end, new methods for systemic, multi-criteria evaluation are being developed as part of the project. In addition to purely technical and economic points, this also includes ecological, regulatory, acceptance and site-specific aspects.
From CO2 to olefins and higher alcohols.
All these steps are grouped into work packages and clearly distributed: Ruhr-Universität Bochum and Leuchtstoffwerk Breitungen are focusing on catalyst synthesis and characterization as well as up-scaling. Fraunhofer UMSICHT is dedicated to thermal and electrocatalysis and couples both processes. Phoenix schließlich übernimmt Prozessgasanalytik und -bereitstellung sowie – gemeinsam mit dem Fraunhofer-Institut – die Systemintegration.
"Together, we are working out an economical way to produce olefins and higher alcohols from the released CO2," says Dr. Heiko Lohmann of Fraunhofer UMSICHT, outlining the objectives of CO2-Syn. "They play an important role for industry as basic chemicals or alternative fuels." For example, the olefin ethylene is an important ingredient in the chemistry for the production of plastics such as polyethylene or polystyrene. Ethylene is currently produced on the basis of fossil raw materials such as natural gas. The higher alcohols are also important chemical value products. They are used, for example, as solvents and thinners for paints or as fuel additives.
- Ruhr Universities Start Building Up Research Alliance
15th February 2022,
75 Million for Cutting-Edge Research.
Pictured (from left): Rector Prof. Manfred Bayer (TU Dortmund University), NRW Minister President Hendrik Wüst, Rector Prof. Martin Paul (Ruhr University Bochum), NRW Minister of Science Isabel Pfeiffer-Poensgen and UDE Rector Prof. Ulrich Radtke. © Land NRW/Ralph Sondermann
The starting signal has been given: In the NRW State Chancellery, the rectors of Ruhr University Bochum, TU Dortmund University and University of Duisburg-Essen (UDE) signed the extended cooperation agreement for the establishment of the "Research Alliance Ruhr". Minister President Hendrik Wüst and Science Minister Isabel Pfeiffer-Poensgen also handed over the allocation letter for funds amounting to 75 million euros for the start-up phase. The new research alliance was developed as part of the Ruhr Conference initiated by the state government.
The three universities are now establishing four new research centers and one college under the umbrella of the University Alliance Ruhr. In the centers, the universities are pooling their research in fields such as health, sustainability, digitization and energy. The college will invite visiting scientists from abroad to the Metropole Ruhr. The full expansion of the Research Centers and College is to be achieved by 2025. The aim is to establish a top-class international research alliance.
"North Rhine-Westphalia is the densest university and science location in Europe, and our science is excellent," says Minister President Hendrik Wüst. "The innovations created here are the opportunities of tomorrow. With the Research Alliance Ruhr, we are giving the science location of North Rhine-Westphalia another powerful boost on the way to international top-level research. In this way, we are turbo-charging the University Alliance Ruhr." The Minister President continued, "With the funding of the Research Alliance Ruhr, we are now driving forward cooperation between the universities in the Ruhr region. We want even more bright minds from all over the world to work with us on the big questions of the future. The University of California shows how important cooperation between universities is. It has been driving digital innovation worldwide for 30 years."
Taking excellent research to a new level
"With today's signing of the cooperation agreement and the handover of the allocation letter in the amount of 75 million euros, we are seizing the opportunity to raise the excellent research of Ruhr University Bochum, TU Dortmund University and the University of Duisburg-Essen to a new level," says Science Minister Isabel Pfeiffer-Poensgen. "Together with the three universities, our goal is to create a highly innovative university alliance in the Ruhr region with the Research Alliance Ruhr, which will develop solution options for important issues facing our society while meeting the highest scientific excellence criteria - especially in international comparison. As the state government, we thus want to contribute to the Research Alliance stimulating further promising research cooperation and advancing our state with forward-looking research impulses and innovation opportunities."
"With the Research Alliance, the cooperation between the three universities reaches a new quality. Together, we can now expand our strengths in a targeted manner," emphasizes Prof. Ulrich Radtke, Rector of the University of Duisburg-Essen. "We are creating attractive research conditions that will enable us to attract even more top people from the international scientific community to the Ruhr region," adds his colleague from Bochum, Prof. Martin Paul. TU Rector Prof. Manfred Bayer adds, "The entire region will benefit from the strengthening of the science location, because our research deals with the pressing questions of the future." All three welcome the state government's support: "With the allocation, funding is now secured for the first three years and we can take off together."
Four research centers and one college
The Research Alliance Ruhr was initiated as part of the Ruhr Conference of the NRW state government. The four Research Centers deal with the topics "One Health," "Chemical Sciences and Sustainability," "Trustworthy Data Science and Security," and "Future Energy Materials and Systems." In addition, a "College for Social Sciences and Humanities" is being established. In total, up to 50 new professorships will be created, as well as numerous positions for mid-level faculty. Preparations for the first appointment procedures have already begun.
- Pesticide Control on the Nanoscale
7th February 2022,
New at UDE: Anzhela Galstyan . Read original article
© UDE/Frank PreußHarmful bacteria have declared war on Dr. Anzhela Galstyan. At the Faculty of Chemistry, the new WISNA* Junior Professor of Nanomaterials in Aquatic Systems is researching, among other things, the synthesis of photoactive nanomaterials that can eliminate microorganisms at the nanoscale.
What's behind photoactive nanocarriers? "These are molecules of a chemical compound that - when irradiated with light - form a reactive oxygen species (ROS)," says Professor Galstyan. ROS is used, for example, in so-called photodynamic antibacterial therapy (PDT). It is used to combat multi-resistant bacteria - so-called superbugs - and treat biofilm-associated infections. "The toxic effect results from the potential of ROS to react with nucleic acids, proteins or cell membranes, causing cell death," the 40-year-old explains. "A major advantage of light-activated substances (photosensitizers) is that they can be used for photodynamic therapy as well as for imaging bacteria."
ROS and chemical reactions triggered by light are also proving useful in treating wastewater. Previously, it had to be pretreated and secondary contaminants had to be removed. "In our group, we use electrospinning technology to produce photoactive nanofiber membranes that can remove not only microorganisms but also other pollutants through ROS production. This eliminates the need for additional chemicals. This is attractive for sustainable disinfection and decontamination of natural or industrial waters," says the UDE professor.
Anzhela Galstyan studied chemistry from 1998 to 2002 at Yerevan State University, Armenia. She earned her master's degrees from the University of Siegen in 2004 and from the Armenian university in 2005. After a very good PhD (2010), she conducted research at the Center for Nanotechnology at the University of Münster (2011/12), at the European Institute for Molecular Imaging at the University Hospital there (2013-2016), and since 2016 she has led a research group at the Center for Soft Nanoscience at the University of Münster. Her research has received several awards.
*The WISNA junior professorship is part of the program for the promotion of young scientists (WISNA) established by the German government. It is intended to offer young researchers a transparent and predictable path to a lifetime professorship. Throughout Germany, 1,000 additional WISNA professorships are to be funded, 23 of which are at UDE. The Center for Water and Environmental Research (ZWU), the University of Duisburg-Essen (UDE) profile focus areas of water research and nanoscience, and the Center for Nanointegration Duisburg-Essen (CENIDE) are excited about Galstyan's calling.
https://www.uni-due.de/2022-02-04-schaedlinge-nanoebene-anzhela-galstyan
- Kickstart for Application-Oriented Energy Projects
1st February 2022,
German-Dutch Cooperation . Read original article
© Ian Van Landuyt
Nano research at the University of Duisburg-Essen (UDE) enjoys international recognition – Materials Chain members Prof. Dr. Corina Andronescu and Prof. Dr. Doris Segets are involved in two new projects of the Dutch Research Council (NWO). Under the name ElectroChemical Conversion and Materials (ECCM) Kickstart DE-NL, they are now working on innovative ideas in two of a total of 13 transnational projects that aim to bridge the gap between nanoscale materials and their large-scale production in the field of electrochemical energy conversion.
"The combination of nanoscience and electrochemical application and electrocatalysis simply sets UDE apart! We are very happy about the collaboration, which shows that our work in this industry-relevant research field is also internationally visible," Segets summarizes the success.
Together with Dr. A.C. Garcia from the University of Amsterdam (UvA) and industry partner Sensolytics, Andronescu is involved in the project "Imaging oxidation reactions on high surface area anodes for paired electrolysis". Coupling electrochemical methods with scanning electrochemical methods promises to produce more stable electrocatalysts for a more sustainable chemical industry. To this end, the project is investigating the fundamental aspects of imaging techniques as a powerful tool for exploring the activity and stability of electrode materials to be used in electroorganic synthesis.
Segets will work with prof. dr. ir. J.R. van Ommen of Delft University of Technology (TUD), Coatema Machinery and Johnson Matthey of Covestro to conduct research on the "Scalable production of large-area materials with nano-precision for the energy transition." The energy transition requires novel large-scale energy conversion plants, e.g. for the production of hydrogen. Essential components of such plants are electrodes and membranes. The team is working on methods by which they too can be manufactured on a large scale, while working economically with the scarce metals required.
The border region between the Netherlands and Germany is a strong industrial cluster and therefore ideally suited for developing new climate-neutral technologies for energy-intensive industry. The Kickstarter program aims to promote closer cooperation between the Netherlands and Germany. Therefore, in addition to a fixed postdoc exchange, the program is designed in several stages, where further funding is possible, from which the German partner will then also benefit.
The NWO is one of the most important scientific funding bodies in the Netherlands and is committed to quality and innovation in science. The NWO falls under the jurisdiction of the Ministry of Education, Culture and Science.
- A Podcast on "Engaged Science"
31st January 2022,
New Podcast Series from the Junge Akademie Wissen - Handeln? . Read original article
© Die Junge AkademieIn what ways can and should scientists engage in society beyond academic discourse and contribute to public debates or political decision-making processes? The members of the working group "Engaged Science" talk about this in their new podcast series with scientists of high visibility. Materials Chain member Prof. Doris Segets will also be part of this series.
For the podcast series, two members of the "Engaged Science" working group each invite one scientists to talk about their motivations and successes, but also about the challenges, dangers and limitations of their activities. Together, they reflect on whether and how scientists need to actively communicate their research findings beyond the professional audience, and whether good, engaged science means getting involved in social debates, engaging in policy advocacy, or even animating critical activism.
In the first episode, Bénédicte Savoy talks with Young Academy members Isabelle Dolezalek and Birgit Nemec. An art historian, she participates in public debates on cultural heritage restitution and a new relational ethic between Europe and Africa in a variety of ways through her research on art theft. In this interview, she shares experiences and insights she has gained in relation to her social engagement. She shares the role that both specific people and coincidences have played in this process, and what motivates her to go public with her research.
The podcast episodes will initially appear weekly and will soon also be available on all known streaming platforms such as Spotify, iTunes or Deezer.
The Junge Akademie was established in 2000 as the world's first academy for outstanding young scientists. Its members come from all scientific disciplines as well as from the artistic field - they explore the potential and limits of interdisciplinary work in ever new projects, want to bring science and society into conversation with each other and new impulses in the science policy discussion.
For information on the "Engaged Science" working group and its members
- Where Water Meets Metal
19th January 2022,
Unexpected Energy Storage Capability . Read original article
Dr. Mahnaz Azimzadeh Sani and Dr. Julia Linnemann (from right) are part of the team that found unexpectedly high electrochemical capacities on individual gold and platinum nanoparticles.
© RUB, KramerResearchers from the RESOLV Cluster of Excellence have used current and voltage measurements on individual nanoparticles to determine that the capacitively stored charge at platinum interfaces can be significantly higher than previously thought. They attribute this to a special arrangement and bonding of water molecules. To this end, the international team led by Prof. Dr. Kristina Tschulik, whose ideas were awarded an ERC Starting Grant from the European Research Council in 2020, cooperated with partners from France and Israel. The authors describe their findings in the journal Angewandte Chemie - online, published Dec. 19, 2021.
Although interfaces between metals and water are the local areas where crucial processes of energy technologies such as water splitting occur, little is known about their structure and changes during such processes. For more than 100 years, the scientific description of such interfaces has been dominated by the model of the so-called electrochemical double layer. It states that charge carriers of an aqueous solution are increasingly arranged in the boundary region to the metal in order to compensate for excess electrical charges on the metal side. In the process, the opposing charges are separated by water molecules. Similar to a technical plate capacitor, this nanoscopic charge separation in the interface allows energy to be stored and retrieved later. Processes in which the molecular structure of the electrochemical double layer changes are relevant to many green technologies, such as supercapacitors and fuel cells.
Nanoparticles, which are thousands of times smaller than the diameter of a human hair, are increasingly being studied for such technical applications. Because of their advantageous ratio of process-relevant surface area to volume, they offer particularly good conditions for this. The Iranian scientist Dr. Mahnaz Azimzadeh Sani, who was funded by the German Academic Exchange Service, used so-called colloidal nanoparticle dispersions. Here, nanoparticles are separated from each other and finely dispersed in aqueous solution and randomly strike a live microelectrode every now and then. With the help of computer-aided molecular dynamics simulations, commonalities and differences of voltage-dependent measured capacitive currents of different types of nanoparticle dispersions could be interpreted. The unexpectedly high capacitances are attributed to dissolved charged particles that increasingly accumulate in interstices of a compact water layer bound to platinum (and more weakly to gold) and an adjacent water layer of a different arrangement.
- A Treasure Map for the Realm of Electrocatalysts
13th January 2022,
Materials Research.
A view of the sputtering facility at RUB that was used to produce the material libraries.
© Christian NielingerThe number of possibilities complicates the search for promising materials. A German-Danish team has developed an efficient method for doing so.
Efficient electrocatalysts are hidden in materials composed of five or more elements, which are needed, for example, for the production of green hydrogen. A team from Ruhr University Bochum (RUB) and the University of Copenhagen has developed an efficient method for identifying promising candidates in the countless possible materials. To do this, the researchers combined experiments and simulation. They report in the journal Advanced Energy Materials, January 5, 2022.
Millions of systems are conceivable
High-entropy alloys, or HEAs, are chemically complex materials consisting of mixtures of five or more elements. The interesting thing about them is that they offer completely new possibilities for the development of electrocatalysts. These are urgently needed to make energy conversion processes more efficient, such as for the production and use of green hydrogen. "The problem with HEAs is that, in principle, millions of high-entropy systems are possible, and each system involves tens of thousands of different compositions," explains Prof. Dr. Alfred Ludwig, who heads the Materials Discovery and Interfaces chair at RUB. Conventional methods and traditional high-throughput procedures can hardly cope with this complexity.
Five sources, six constellations
In their work, the researchers describe a new method to help identify promising high-entropy alloys for electrocatalysis. In the first step, the team developed a way to produce as many potential compositions as possible. To do this, they used a sputtering system that simultaneously applies the five starting materials involved to a carrier.
The RUB electrochemistry team then examined the carriers coated in this way for their electrocatalytic activity and stability. To get even closer to the composition of the materials, the team matched these data from the experiment with a large simulation data set provided by the researchers at the University of Copenhagen.
- Catalyst Surface Analysed at Atomic Resolution
12th January 2022,
Catalyst surfaces have rarely been imaged in such detail before. And yet, every single atom can play a decisive role in catalytic activity.. Read original article
Members of the Bochum-based research team in the lab: Weikai Xiang, Chenglong Luan and Tong Li (from left to right) © PrivatA German-Chinese research team has visualised the three-dimensional structure of the surface of catalyst nanoparticles at atomic resolution. This structure plays a decisive role in the activity and stability of the particles. The detailed insights were achieved with a combination of atom probe tomography, spectroscopy and electron microscopy. Nanoparticle catalysts can be used, for example, in the production of hydrogen for the chemical industry. To optimise the performance of future catalysts, it is essential to understand how it is affected by the three-dimensional structure.
Researchers from the Ruhr-Universität Bochum, the University of Duisburg-Essen and the Max Planck Institute for Chemical Energy Conversion in Mülheim an der Ruhr cooperated on the project as part of the Collaborative Research Centre “Heterogeneous oxidation catalysis in the liquid phase”.
At RUB, a team headed by Weikai Xiang and Professor Tong Li from Atomic-scale Characterisation worked together with the Chair of Electrochemistry and Nanoscale Materials and the Chair of Industrial Chemistry. Institutes in Shanghai, China, and Didcot, UK, were also involved. The team presents their findings in the journal Nature Communications, published online on 10 January 2022. Particles observed during the catalysis process
The researchers studied two different types of nanoparticles made of cobalt iron oxide that were around ten nanometres. They analysed the particles during the catalysis of the so-called oxygen evolution reaction. This is a half reaction that occurs during water splitting for hydrogen production: hydrogen can be obtained by splitting water using electrical energy; hydrogen and oxygen are produced in the process. The bottleneck in the development of more efficient production processes is the partial reaction in which oxygen is formed, i.e. the oxygen evolution reaction. This reaction changes the catalyst surface that becomes inactive over time. The structural and compositional changes on the surface play a decisive role in the activity and stability of the electrocatalysts.
For small nanoparticles with a size around ten nanometres, achieving detailed information about what happens on the catalyst surface during the reaction remains a challenge. Using atom probe tomography, the group successfully visualised the distribution of the different types of atoms in the cobalt iron oxide catalysts in three dimensions. By combining it with other methods, they showed how the structure and composition of the surface changed during the catalysis process – and how this change affected the catalytic performance.
“Atom probe tomography has enormous potential to provide atomic insights into the compositional changes on the surface of catalyst nanoparticles during important catalytic reactions such as oxygen evolution reaction for hydrogen production or CO2 reduction,” concludes Tong Li.
- Impressions of the Study Program
10th January 2022,
NanoEngineering . Read original article
© NanoEngineering, UDEWhy study NanoEngineering at the University Duisburg-Essen (UDE) - and what's behind it? Accompanied by a camera, student Eline Reger takes us on a tour around the campus in Duisburg. The resulting video provides insights into laboratories, students' experiences and the world of nano research.
Questions are answered such as - what actually is nano? And what sets NanoEngineering apart from other engineering disciplines? Behind the scenes of a clean room and Nanoenergie Technikzentrum (NETZ) labs, such as the large synthesis lab or the battery lab, students also talk about their everyday life at university and what they are working on in the internships and bachelor's, master's or doctoral theses that accompany their studies.
NanoEngineering is an interdisciplinary bachelor's and master's degree program at UDE that is jointly led and developed by electrical and information engineering, mechanical and process engineering, and physics. The content focuses on nanoelectronics and nanooptoelectronics as well as nanoprocess engineering.
- Everything but Superficial
6th January 2022,
57th UNIKATE on the Subject of Catalysis. Read original article
The high-performance computer magnitUDE, whose calculations also point the way in the search for suitable catalyst materials.
© UDEWhat does catalysis have to do with the energy transition and which everyday phenomena can be traced back to catalytic processes? Questions like these are answered in the current issue of UNIKATE* from the UDE. It is dedicated to the research of the Collaborative Research Center/Transregio 247. This has set itself the goal of understanding the complex processes of catalysis and, based on this, developing customized solutions for various applications.
The term "catalysis" is derived from the Greek word katálysis for "dissolution". In the late 19th century, the German chemist and Nobel Prize winner Wilhelm Ostwald established the definition that is still commonly used today, according to which a catalyst is a substance that enables a chemical reaction or increases its rate without appearing in its final product.
In Chinese, the character for "catalyst" also means "matchmaker," metaphorically describing the function of a catalyst: it enables starting materials to react with each other and combine to form something new.
Since July 2018, the University of Duisburg-Essen (UDE), Ruhr University Bochum (RUB), the Max Planck Institute for Chemical Energy Conversion, the Max Planck Institute for Coal Research, and the Fritz Haber Institute of the Max Planck Society have been working closely together within the Collaborative Research Center/Transregional Collaborative Research Center (SFB/TRR) 247. While many of the catalysts currently in use were discovered by trial and error, the researchers of the SFB/TRR 247 have set themselves a clear goal: in the long term, they want to specifically design catalysts down to the level of atoms in order to selectively enable the desired reactions, i.e. without undesired by-products. Rare precious metals are to be replaced by readily available and less expensive materials. To this end, the researchers will deepen their basic knowledge of catalysis and, in particular, decipher the reaction mechanisms on the surfaces.
UNIKATE is published twice a year and presents UDE research results and projects on a current topic. Individual issues can be purchased in bookstores nationwide for 7.50 euros. Subscriptions are available from the Heinrich Heine bookstore in Essen (Viehofer Platz 8).
* UNIKATE 57: Catalysis - anything but superficial. ISBN: 978-3-934359-57-4
- Faster to Materials for the Energy Turnaround
21st December 2021,
Five Year Funding by the Mercator Research Center Ruhr.
Sputtering of material libraries for electrocatalysts is one of the methods used in the project.
© Lars BankoThe Ruhr University Alliance (UA Ruhr) project aims to break a vicious circle.
In order to achieve the energy transition, new materials are needed, for example for fuel cells and the electrolysis of water to produce so-called green hydrogen. The materials used so far are scarce and expensive. In a joint project, researchers from UA Ruhr are searching for new candidates that are inexpensive, non-toxic and efficient. The project, called DIMENSION, will be funded by the Mercator Research Center Ruhr (MERCUR) for five years starting in January 2022 with around 1.8 million euros.
Finding worthwhile candidates quicklyEfforts to date have not been enough to limit global warming to 1.5 degrees Celsius. If we want to move away from fossil fuels, electricity is moving to the forefront, and with it electrochemical processes that are needed, for example, to produce hydrogen by electrolysis. "For Germany as an industrial location - and beyond - it is therefore absolutely critical to success to develop new and powerful electrochemical functional materials that are based on available elements and can be produced cost-effectively on the required scale," says Prof. Dr. Alfred Ludwig, holder of the Chair of New Materials and Interfaces at Ruhr University Bochum.
This is where the DIMENSION project - Determining materials for energy conversion - Establishing a fast track towards processing and evaluation - comes in by breaking a vicious circle: In order to test the suitability of a new material in use, it must be produced in sufficient quantities and integrated into components. This requires scale-ups and process developments that are only worthwhile for promising candidates and are not tackled without concrete prospects of success. DIMENSION therefore combines accelerated evaluation of new materials with accelerated development of synthesis and processing methods. This is achieved through high-throughput experiments and materials informatics that lead precisely to active materials with outstanding electrocatalytic properties. They are processed and tested almost simultaneously at the system level. This creates a universal method to filter out promising candidates early and develop them to industrial applicability.
- Better Materials for 3D Laser Printing
13th December 2021,
DFG Priority Program Extended. Read original article
© Prof. Jan T. Sehrt / RUBThe starting signal was given in 2018, and now the 2nd round is underway: the German Research Foundation (DFG) is continuing to fund Priority Program (SPP) 2122 "New materials for laser-based additive manufacturing". Over the next three years, laser-based 3D printing and the materials used for it will be further developed to make the process even better. The University Duisburg-Essen (UDE) remains the coordinating university. In total, the DFG is funding 12 projects with around 25 doctoral students.
Fast and precise: Laser-based 3D printing has become established and revolutionized manufacturing technology. Lasers in production are becoming increasingly powerful and brilliant, but the materials available for the necessary processing are often completely inadequate. To this day, additive manufacturing uses metal powders that were developed over 50 years ago for a completely different process. However, in modern laser-based additive processes, these powders lead to process instabilities as well as porosity and defects in the component.
The first funding phase of SPP 2122, coordinated by the UDE and the Center for Nanointegration Duisburg-Essen (CENIDE), therefore focused on the starting materials. The research team developed new materials adapted to the laser-based production process and focused on the synthesis of new metal and polymer powders. This significantly expanded the range of powder materials.
"For the first time, we have succeeded in merging materials development with photonics research," explains SPP spokesperson Prof. Dr. Stephan Barcikowski. The researchers believe that there is considerable potential in targeted materials development for photonic production. It is important here to understand the complete process chain of a product - from powder modification to powder flow properties and powder bed laser printing to microstructural properties - and not just its individual steps.
The participating research groups have published their results from the first funding phase in more than 55 publications and special issues in scientific journals. This coming March, the highlights of the first funding phase will be presented to the public in a bundled form for the first time.
In the coming years, the researchers plan to continue working in cross-project tandems and to tackle joint interlaboratory studies including targeted research data management. In doing so, progress for metal- and polymer-based starting materials in industrialization, standardization, robustness and fundamental understanding along the entire process chain of laser-based 3D printing will be consolidated.
- Physicists Control Ultrafast Electron Dynamics in Perovskite Materials
13th November 2021,
Materials Research for Renewable Energy. Read original article
The physicists at TU Dortmund want to develop modern materials for photovoltaics: (from left) TU Rector Prof. Manfred Bayer, Erik Kirstein, Dr. Evgeniy Zhukov, Dr. Nataliia Kopteva, Eiko Evers, Prof. Dmitri Yakovlev and Dr. Dennis Kudlacik. © Oliver Schaper/TU Dortmund
In their search for new high-performance materials for solar cells, a team from Technical University (TU) Dortmund, together with international partners has made an important discovery: ultrahigh-resolution studies on a time scale of trillionths of a second show that the electron dynamics in pervoskite crystals are significantly determined by lead. This result illustrates that the material properties can be strongly modulated by the exchange of this element. The results have been published open access in the prestigious journal Advanced Materials.
Organic lead halogens with a perovskite crystal structure are considered to be extremely promising materials for the development of high-performance yet low-cost solar cells. Over the past ten years, the quality of such perovskites has been improved enormously, so that they already achieve a similarly high light yield to conventional silicon solar cells. They can be tailored to absorb not only all visible sunlight but also near-infrared radiation and convert it into electricity. Their production, on the other hand, requires little technological effort and also consumes comparatively little energy. Perovskites are not only interesting for solar cells, but could in principle also be used for LEDs or X-ray detectors. However, the durability of the components still leaves much to be desired.
Why the lifetime of perovskite devices is limited is not yet understood. A large number of research groups around the world are working hard on this question in order to develop new materials for the energy transition. One key is understanding the electronic and magnetic properties of the materials at the atomic level. Here, a team from the Faculty of Physics at TU Dortmund University, together with other colleagues from Germany, Russia and Switzerland, has now been able to make significant progress.
Strong interaction with lead observed in experiment
The group led by TU Professor Dmitri Yakovlev investigated ultrafast interaction processes between optically excited charge carriers and their environment in perovskite crystals. On the one hand, they were able to show that the magnetic properties can be controlled ultrafast when optical pulses with a duration of trillionths of a second are used. This demonstration of controllability is of particular interest for potential new applications. Second, it was shown that the lifetime of magnetization of optically generated carriers is limited when they interact with nuclear spins. By far the most intense losses were observed in the interaction with the nuclear spin of lead. Thanks to this finding, the material can now be further developed in a targeted manner by replacing lead with other elements in series of experiments.
The research work is a contribution to the Research Center "Future Energy Materials and Systems" of the University Alliance Ruhr.
- Making the Manufacture of Chemical Products Sustainable
4th November 2021,
Junior Research Group .
Electrochemical cell for the conversion of organic chemicals on a laboratory scale.
© UMSICHT, Alina GawelThe junior research group "H2Organic" is working on a green electrochemical process under the leadership of Dr. Daniel Siegmund, group leader "Electrocatalysis" at Fraunhofer UMSICHT and post-doctoral researcher at Ruhr-Universität Bochum (RUB) supervised by Materials Chain member Prof. Ulf-Peter Apfel.
It all started with a competition. With his idea of using innovative materials for the electrocatalytic hydrogenation of organic chemicals, Siegmund applied to the "BMBF NanoMatFuture" competition for young scientists. The aim of the competition was to promote excellence in the field of materials and nanotechnology by providing young scientists with good starting conditions. A few months later, the confirmation: Siegmund and his group "H2Organic" can start their research in October 2021. The Federal Ministry of Education and Research is funding the project with around 1.8 million euros.
The project brings together science and industry. Together, they want to use electricity from renewable sources with the help of an electrochemical synthesis process to produce chemical products with a green footprint. "Many manufacturing processes in the chemical industry cannot be described as sustainable even in 2021," Siegmund says, explaining his motivation. "Often they are directly or indirectly based on fossil fuels or result in potentially harmful by-products. These disadvantages can be minimized by innovative electrochemical processes."
For example, green power can eliminate the need for large amounts of chemical oxidizers and reducers and help avoid waste products. In addition, electrochemical processes are easy to control and generally do not require complex reaction conditions such as high temperatures or pressures.
Using materials research to create an effective electrochemical process
The focus of the "H2Organic" researchers is on the process of hydrogenation - one of the standard reactions both in the laboratory and on a large industrial scale, in which hydrogen is transferred to organic chemicals. For example, this process is used in the production of margarine. "Instead of classical hydrogenation, we want to develop a sustainable, electrochemical process that brings the above-mentioned advantages," says Siegmund. "In doing so, we are looking at all the necessary steps to design and optimize such a process - starting with the basic design of the electrochemical reactor and specially adapted catalyst materials as reaction accelerators, right through to corrosion-resistant housing components and seals." The scientists always keep in mind that the reaction cell they have developed should also have the potential to be transferred from small laboratory scale to industrial size.
An important starting point in the project: the substitution of expensive precious metal-based catalysts such as palladium or platinum in favor of innovative precious metal-free catalysts. Siegmund: "We are using conductive transition metal sulfides for this purpose, which can be produced much more cheaply and are less harmful to the environment. Incidentally, this catalyst choice is inspired by a high structural affinity of these materials to natural hydrogen-processing enzyme centers."
Another key problem for the researchers: translating a catalytically active material into an efficient electrode. To solve that, they are developing and evaluating core reactor components - incorporating the fabricated catalysts - in electrochemical hydrogenation flow cells designed in-house.
"At the end of the project, we want to help establish innovative, sustainable electrocatalytic synthesis processes in the chemical industry", says Siegmund, summarizing the intended outcome of the research work. "In addition, we want to close the development gap between fundamental catalyst research and process engineering applications in electrocatalysis."The joint project "Innovative Materials for the Electrocatalytic Hydrogenation of Organic Substrates (H2Organic)" is funded by the German Federal Ministry of Education and Research under the "From Material to Innovation" program.
- It doesn't get more accurate than this!
19th October 2021,
New Sensor Detects Low Air Humidity.
Scanning electron microscopy of a Mo2CTx MXene multilayer.
© UDE/Hanna PazniakMeasuring air humidity is important in many areas. However, conventional sensors in hygrometers have so far not been able to determine a very low water vapor content. Physicists at University Duisburg-Essen (UDE) and the Yuri Gagarin Technical University in Russia have now developed a new sensor. It detects even the smallest amounts of water molecules that sink to its surface. The detector is based on highly conductive materials known as MXenes.
Good indoor air is not only important for health. Certain ambient conditions are also needed in production or laboratories, for example in biomedicine or microelectronics. It must be possible to control these precisely. Although powerful humidity sensors are built into commercial measuring devices, they are not able to detect water vapor concentrations below 50 ppm, i.e. below 0.3% relative humidity. Consequently, such sensors are not suitable for all purposes.
This problem was tackled by the physics team from UDE and the Russian University Yuri Gagarin in Saratov with a completely new strategy. They used two-dimensional nanometric materials. These can detect minute amounts of water molecules that sink to their surface. "In this way, the sensor performance improves enormously - the detection limit is pushed far below the previous state of the art. More is really not possible!" enthuses UDE experimental physicist Dr. Hanna Pazniak, who played a key role in the development.
These highly conductive materials are called MXenes, or more precisely: Mo2CTx MXenes. They consist of compounds of transition metal carbides or transition metal nitrides. The compounds are stacked into layers and are only a few atoms thick. The advantage: The new sensors are ultra-thin and highly sensitive. "They detect water vapors down to 10 ppm, or 0.06% relative humidity. That's the lowest value known so far," Pazniak says. The sensors are also promising in another respect: they can be used in mass production.
The research results were recently published in the well-known journal Advanced Materials (https://doi.org/10.1002/adma.202104878).
More information:
Dr. Hanna Pazniak, Faculty of Physics, hanna.pazniak@uni-due.de
Prof. Dr. Ulf Wiedwald, Faculty of Physics, ulf.wiedwald@uni-due.de - International Team Gains New Insights into Molecular Interfaces
19th October 2021,
Potential for Application in Innovative Technology.
Dr. Giovanni Zamborlini, Henning Sturmeit and Prof. Mirko Cinchetti conduct research at the Faculty of Physics at TU Dortmund.
© Felix Schmale/TU DortmundMolecular interfaces formed between metals and molecular compounds offer great potential as components for future optoelectronic and spintronic devices. Porphyrin molecules are a promising building block for such interfaces. In an international research collaboration, Prof. Mirko Cinchetti, Dr. Giovanni Zamborlini, and Henning Sturmeit from the Department of Physics at Technical University (TU) Dortmund have now investigated important properties of this molecule and thus brought it closer to practical applications. They recently presented their results in the renowned nanotechnology journal Small.
The amount of data grows and grows – and with it, the demand for new options for data storage. One possibility is to store information in molecules. They have the advantage of constantly maintaining the same structure and are, as a consequence, very reliable – assuming the lasting transfer of information into the molecules can be managed. Researchers in the area of spintronics, a specialized field in nanoelectronics, are working to make this possible.
An international research group led by Prof. Mirko Cinchetti and Dr. Giovanni Zamborlini from TU Dortmund has now been able to gain important insights into an interesting porphyrin-metal interface. Porphyrins contribute to important functions in living systems: They occur in the chlorophyl that enables photosynthesis in plants, for example, as well as in the hemoglobin in human blood. In this research project, the scientists used vapor deposition to coat a copper surface with nickel-containing porphyrin molecules – that is, each molecule carried one nickel atom in the center. They then exposed the porphyrin-copper interface to the gas nitrogen dioxide. They found that the nickel atom in the porphyrin can be reversibly switched to a higher spin state, which no one had previously been able to observe at room temperature. This mechanism could be used in the future to store information in porphyrines, or to develop extremely sensitive sensors to detect the poisonous gas nitrogen dioxide.
Porphyrin-copper interface is extremely interesting for future applications
The researchers have, in addition, discovered another useful effect: In potential future applications in electrical components, current would flow through the porphyrin-copper interface. In the experimental study it became clear that the states responsible for current flow will not be influenced by the spin-switching process – an important precondition to enable the production of multifunctional components that can selectively change numerous physical properties when external stimuli are applied. "All this makes the porphyrin-copper interface extremely interesting for future technical applications," says Prof. Mirko Cinchetti.
This work is the result of an international cooperation involving TU Dortmund, Research Center Jülich, the University of Trieste, the Italian National Research Council, the University of Erlangen, and the University of Graz. The experiments were conducted primarily at the synchrotron facilities ELETTRA in Trieste (Italy) and Swiss Light Source SLS in Villigen (Switzerland). The teams led by Prof. Mirko Cinchetti and Dr. Giovanni Zamborlini (TU Dortmund University) as well as Dr. Vitaly Feyer and Prof. Claus M. Schneider (Research Center Jülich) were responsible for carrying out and analyzing the measurements, while Prof. Peter Puschnig (University of Graz) provided theoretical work. Prof. Cinchetti carries out research on the project within the framework of his ERC Consolidator Grant. He was awarded this EU funding, worth two million euros, in 2016.
Further Information:
https://onlinelibrary.wiley.com/doi/10.1002/smll.202104779
Prof. Dr. Mirko Cinchetti, Experimentelle Physik VI, +49 231 755 5438, mirko.cinchetti@tu-dortmund.de - The DNA of Super-Magnets
4th October 2021,
Collaborative Research Center/Transregio 270.
"No e-mobility without magnetic materials!" or "No wind power without magnets!" - such slogans are missing in the public discussion about sustainable energy supply. However, magnets are of fundamental importance. In 2020, the German Research Foundation approved the SFB/TRR 270 - where Technical University (TU) Darmstadt, University Duisburg-Essen (UDE), Research Center (FZ) Jülich and MPIE Düsseldorf are working on the "Hysteresis design of magnetic materials for efficient energy conversion". Materials Chain member and UDE-spokesperson Prof. Michael Farle is also involved in the project.
In the field of sustainable energy supply, significant developments have taken place for the better in recent years. But especially in everyday life, there are still many areas that could benefit greatly from innovative research on magnetic materials. In refrigerators and air conditioners, for example, 120-year-old gas compression cooling is still the standard. It requires refrigerants that are flammable or toxic, damage the Earth's ozone layer and contribute to global warming. "It's quite astonishing that this old technology has persisted so much despite its disadvantages," says Prof. Oliver Gutfleisch of TU Darmstadt. "At the same time, we should be aware that the energy shift is above all also a material shift."
As spokesman for SFB/TRR 270, Gutfleisch and his fellow campaigners are focusing on materials whose properties also already play a major role in our everyday lives, but in his eyes should play an even greater role: magnets. "Each of us uses 50 to 100 magnets all the time without realizing it," says the researcher. But that's just the beginning, he said:
"Magnets are increasingly becoming key to high-tech fields such as e-mobility, robotics, the Internet of Things, Industry 4.0. or sustainable energy."
The wind energy sector, for example, is growing globally by around ten percent per year. This requires about half a ton of the high-performance permanent magnet material Nd-Fe-B per megawatt of power. Extrapolating this figure, a 10-megawatt turbine in a modern "gearless" offshore plant needs five tons - if it can do without an energy-consuming transmission to adjust the speed of rotation from the rotor hub to the generator shaft. But even the engine of an electric car needs to process about two kilograms of magnet material. Every one percent increase in the efficiency of the magnet material would increase the range of an e-car by 20 km. "That's certainly something you would think about if you were stranded in an e-mobile 19 km from the nearest e-fueling station." Farle from UDE adds.
But to get the most out of the materials in question, the fundamental mechanisms behind the processes would first have to be better understood down to the atomic scale - at the DNA level, so to speak. The key here - understanding magnetic hysteresis in the context of microscopic conditions (such as local chemical compositions, crystalline structures) in multi-element alloy systems. State-of-the-art theoretical and experimental methods - for example using additive manufacturing capabilities - are being used to search for this key, including in SFB/TRR 270.
Further information:
https://www.tu-darmstadt.de/sfb270
Prof. Michael Farle, 0203 379 2075, michael.farle@uni-due.de - Nanoparticles by Laser Beam
4th October 2021,
Berthold Leibinger Prize.
Prof. Bilal Gökce (left) and Prof. Stephan Barcikowski.
© Berthold Leibinger StiftungWhether in physics, mechanical engineering or metrology, industrial laser applications are here to stay. In the chemical industry, however, the technology has not yet arrived. The team from University of Duisburg-Essen (UDE) led by Materials Chain members Prof. Stephan Barcikowski and Prof. Bilal Gökce wants to change that. The scientists have now been awarded the prestigious Berthold Leibinger Innovation Prize for their research.
High-purity laser-generated nanoparticles are ideal for applications in the chemical industry or in additive manufacturing. They can be produced by so-called laser ablations without contact and without further additives. For this purpose, metals or metal alloys are usually bombarded with laser beams in water. These nanoparticles are much purer than those produced in the chemically synthetic variant. The process is also resource-efficient: 100 percent of the metal removed is converted into nanos, and the liquid is even recovered. Until now, however, they have not been widely used because classical lasers can only produce a few milligrams of nanoparticles per hour.
The completely new approach developed by the awardees by placing the laser pulses at supersonic speeds has closed the gap between laboratory-scale laser synthesis and industrial-scale synthesis, making the use of laser-generated nanoparticles available to companies in pre-series development. This can facilitate the production of specialty chemicals used primarily as 3D printing materials and catalysts.
Barcikowski is a professor of technical chemistry at UDE, and Gökce was a research group leader on his team until the spring; he now holds the chair of materials for additive manufacturing at the University of Wuppertal. They accepted the third prize, worth 20,000 euros, at the end of September in the presence of the high-ranking jury.
The Innovation Award has been presented every two years since 2000. It recognizes and promotes scientists who are breaking new ground in the application of laser light.
Further information:
https://www.leibinger-stiftung.de/de
Prof. Dr. Stephan Barcikowski, Technical Chemistry, Tel. 0201/18 3-3150, stephan.barcikowski@uni-due.de - Research Group Extended Again
25th September 2021,
Nanoparticles for Every Application.
© UDE/CENIDE
Six years ago, there was great joy in the nanosciences at the University Duisburg-Essen (UDE): the German Research Foundation (DFG) established a new research group (FOR 2284). Its goal: to develop systematic design rules so that complex nanoparticles can be produced specifically in the gas phase. After 2018, the DFG has now decided for the second time to continue funding the group. Around 1.8 million euros will flow to the UDE until 2024.
Whether medical diagnostics, battery storage, electrocatalysis or printable electronics: functional materials made of inorganic nanoparticles have great application potential. However, only if the manufacturing processes are sufficiently researched and can be scaled up. By making specific changes in the nanometer range, materials can be controlled in terms of optical, electrical, catalytic and magnetic properties, depending on the desired application.
This is where the work of the group led by Materials Chain member Prof. Dr. Christof Schulz, head of the Institute of Combustion and Gas Dynamics at UDE, comes in - with resounding success. Schulz: "In recent years, we have succeeded in bridging the gap between fundamental studies of elementary reactions and the first stages of particle formation and the development of plant concepts that enable transfer to industrial applications. This is only possible through intensive collaboration across disciplinary boundaries."
In deciding to continue funding the research group, the DFG focused on further developing the expertise formed in Duisburg. Over the next two years, the group will now further increase the complexity of the target materials and thus follow up on fundamental findings from the previous period. The reproducible production of so-called metastable substoichiometric particles with special properties plays a role in this. To this end, the influence of turbulent flows must be harnessed in a targeted manner at the plant scale.
Nine projects of the FOR 2284 "Model-based scalable gas phase synthesis of complex nanoparticles" are located at the Institute for Combustion and Gas Dynamics (IVG) and in the Electrical Engineering Department of the UDE as well as at the Institute for Energy and Environmental Technology e.V. (IUTA) are located.
Further information:
https://www.uni-due.de/for2284/
Prof. Dr. Christof Schulz, Faculty of Engineering, Tel.: 0203/379-8161, christof.schulz@uni-due.de - Using Nanoparticles to Improve Charge Transport
24th September 2021,
Topological Insulators.
Images taken with an atomic force microscope show the surface of a bismuth telluride pellet in cross section (left) as well as the electric current flow (center). The superposition of the images (right) makes it clear that the current flows primarily along the edges and interfaces.Three-dimensional topological insulators can conduct electric current on their surface without resistance. However, this effect is difficult to measure. Researchers at Bielefeld University, the Leibniz Institute Dresden and the University Duisburg-Essen (UDE) have now succeeded in doing so. Their study was published in the journal Small.
Physicists at Bielefeld University were able to develop topological insulators based on tiny nanoparticles and thus detect charge transport on the surface. To this end, the material samples were first produced in the working group of Materials Chain member Prof. Schulz at UDE - with a lot of effort: The nanoparticles must, for example, have very clean surfaces and must not react with the environment. Thanks to the special material design, the researchers succeeded in making properties visible that were previously only known in theory.
The investigations were supplemented by terahertz spectroscopy performed by the research team led by Prof. Martin Mittendorff. This involved exciting a sample with electromagnetic waves in the terahertz range and measuring the reflected radiation.
An important step in basic research
"Our study shows that three-dimensional topological insulators can be realized at macroscopic size and at comparatively high temperatures. This is an important step in basic research that could also be important for potential applications - although we are still a long way from that," explains Prof. Gabi Schierning from Bielefeld University. They could be used in quantum computers, for example.
More information:
https://ekvv.uni-bielefeld.de/blog/pressemitteilungen/entry/mit_winzigen_nanopartikeln_zu_besserem
https://ekvv.uni-bielefeld.de/blog/uninews/entry/tiny_nanoparticles_improve_charge_transport - New Chemical Tools for Drug Development
6th September 2021,
Publication in Nature Communications.
The combination of structure-based design, biochemical characterization, and an innovative new cellular system makes it possible to identify promising chemical tools for research on drug ingredients.
© TU Dortmund & Rauh et al. in Nature Communications 2021The protein kinase Akt plays a central role in the development of cancer. Up to now, however, the different functions of its three isoforms have not been elucidated. That is largely due to a lack of suitable biochemical and cellular strategies to clarify the open questions. The research group of Prof. Daniel Rauh in the Department of Chemistry and Chemical Biology at Technical University (TU) Dortmund has now developed chemical tools that can improve the understanding of Akt isoform-specific functions in health and disease, and which could promote the development of next-generation therapeutic agents. These findings were recently published in the renowned scientific journal Nature Communications.
The research group, which also includes doctoral candidates Lena Quambusch and Laura Depta, has developed an innovative cellular model system with which novel Akt isoform-selective inhibitors can be evaluated in a complex environment. In a first proof-of-concept, the chemical tools developed in this way enabled studies of selective effects of Akt inhibition in cancer cells. The novel cellular model system is based on Akt isoform-dependent Ba/F3 cell lines. The structure-guided design approach relies on pyrazinon-based covalent-allosteric Akt inhibitors (CAAIs) that Prof. Daniel Rauh’s team developed in 2019. In combination with a thorough analysis of Akt isoform homology models, a series of different and chemically more accessible pyridin-based CAAIs were designed and synthesized. The design approach was supported by additional structural data from two Akt1 protein crystal structures in the complex with this innovative class of inhibitors, which irreversibly modify the enzyme and lock it into an inactive form. Beyond that, quantitative kinetic measurements were carried out to investigate the binding properties of the synthesized compounds.
The combination of biochemical characterization, structural data, and the cellular systems newly developed here makes it possible to identify promising inhibitors. These ligands are suitable for use as so-called chemical probes for further elucidation studies, and they show promising results in human cancer cells. The work was funded in part by the Federal Ministry of Education and Research, the state of North Rhine-Westphalia, the European Union (European Regional Development Fund), the Drug Discovery Hub Dortmund (DDHD), and the Competence Center KomIT.
Further information:
https://www.nature.com/articles/s41467-021-25512-8
https://onlinelibrary.wiley.com/doi/10.1002/anie.201909857
Prof. Dr. Daniel Rauh, Chemische Biologie, +49 231 755 7080, daniel.rauh@tu-dortmund.de - Applied Plasma Research in Science Magazine Rubin
1st September 2021,
New Release.
The new Rubin issue is all about plasma, the fourth state of matter. © Damian GorczanyOur everyday lives are virtually inconceivable without plasmas. A special edition of Rubin provides insights into their numerous areas of application.
Plasmas help heal wounds, clean up exhaust gases efficiently and extend the shelf life of drinks in PET bottles. They affect our everyday lives in many ways, often without us noticing. The various applications of plasmas are featured in a special edition of Rubin, the RUB’s science magazine. The issue, published on 1 September 2021, gives insights into the activities of two Collaborative Research Centres (SFB/CRC): SFB/TR 87 “Pulsed high power plasmas for the synthesis of nanostructural functional layers” has been operating at RUB since 2010, and CRC 1316 “Transient atmospheric pressure plasmas: from plasmas to liquids to solids” since 2018. Both centres present their research in Rubin.
Plasmas are called the fourth state of matter: in the solid phase, their molecules occupy solid places, whereas there is some freedom of movement in the liquid phase and a lot of more freedom of movement in the gas phase. If more energy is supplied to a gas, the molecules break up and can also be ionized, a plasma is created. The negatively charged electrons separate from the positively charged atomic nuclei and turn them into ions. These free electrons and ions can be accelerated by electromagnetic fields. If the fast electrons collide with other molecules, they can change them in turn by ionising or breaking them down. This process can result in different, sometimes short-lived reactive neutral particles and ions that may be useful for a variety of applications.
- A Tale of Short Time
30th August 2021,
Collaborative Research Center 1242 .
© Frank PreußenWhat happens in a billionth of a billionth of a second in the world of atoms and molecules? This is what the Collaborative Research Center (SFB) 1242 is investigating - and is even making the unimaginably fast visible to the human eye.
21 ... 22 ... If you want to estimate the duration of a second, you can use a convenient trick. At normal speaking speed, we reproduce four syllables in about one second. In everyday life, this may often be quite sufficient - the situation is different in the world of research. Here, much more precise times are important, and fractions of a second can matter. But what is a second?
When the earth was still assumed to rotate uniformly around its own axis, a second was the sixtieth part of a minute, a minute in turn the sixtieth part of an hour, and then as now the day had 24 hours. Around 1885, however, Karl Friedrich Küstner at the Bonn Observatory was able to show that the Earth does not move uniformly, but wobbles slightly around the poles. This doesn't sound like much, but it does have an influence on our lives. Due to these pole fluctuations, an average day on Earth does not last exactly 24 hours, but 23 hours, 56 minutes and 4.0989 seconds. That's why we have the regular leap years and leap seconds to keep in time with our planet.
Since 1967, the length of a second has been precisely defined: It is based on the period of a fixed atomic transition of the 133 cesium atom. This element was chosen because the transition between its ground states was measurable with the electronic devices of the time - although the process occurs exactly 9,192,631,770 times in a second.
In physics, time is considered a directed quantity - that is, it progresses from the birth of the universe to our present time. The researchers of the Collaborative Research Center (SFB) 1242 are investigating various temporal changes. They are looking at condensed matter, basically all the material materials that surround us. The research objects become particularly exciting at the point where they lose their equilibrium and leave their state of rest. This is also how the name of the SFB can be understood: Non-equilibrium dynamics of condensed matter in the time domain.
A kind of flip-book is created: a sequence of rapid events can be observed in slow motion and even fast-forwarded and rewound.
Materials Chain member Professor Uwe Bovensiepen, spokesperson and scientific director, explains what is behind the concept of the time domain: "Physical phenomena can be viewed from different aspects. For example, if you think of light passing through a prism and fanning out in color, you're looking at the spectral domain, a dependence of light color on wavelength."
The domain that the physicists:inside the SFB are looking at is different, as the scientist goes on to explain, "We observe in the time domain. That requires technical tricks and more sophisticated tools. We use an effect that everyone knows from real life: the Doppler effect. This occurs when you hear an ambulance with a siren driving toward you. The frequency and thus the sound changes as the vehicle approaches and passes. It also happens on a small scale when you observe individual atoms in the air."
In the Collaborative Research Center, for example, atoms and their interaction in solid bodies are studied. To do this, electrons are excited, brought out of equilibrium, and we look at how they behave when they return to their initial state. The propagation of such excitations and the coupling with other atoms lead to exciting phenomena here. For example, light can be amplified, or there are structural transformations, for example, from disordered to ordered structures.
Solid-state lasers, whose pulses can be controlled extremely precisely, play an important role in research. Many of the experiments performed are so-called excitation-interrogation experiments (pump-probe in English). A first laser pulse excites a particle, and a second, precisely timed, interrogates the result. The intervals between the two pulses can be regulated and changed extremely precisely.
The result is always a snapshot. If the experiment is carried out again and again and the second laser pulse is set a moment later each time, a whole series of these snapshots is produced. Similar to a sports photographer who can retrace the winning jump at the Olympic Games in many hundreds of individual images, a kind of flip book is also created for the scientists. A sequence of events that actually takes place at breakneck speed can thus be observed in slow motion and even fast-forwarded and rewound.
"Our research takes place in the femto- or attosecond range. An attosecond is a billionth of a billionth of a second, which is almost unimaginably short. For comparison, the universe is about 1018 seconds. And an attosecond is 10-18 seconds long. So the age of our universe relates to a second in the same way that this second relates to the length of the processes we are studying," explains Uwe Bovensiepen.
In the end, the scientists hope that their basic research will contribute to new material properties. These could, for example, improve catalysts or lead to new energy storage systems - a highly relevant topic in view of the climate crisis.
The SFB is currently in its second funding period. "If you want so much money from the German Research Foundation, you have to justify it well," says Uwe Bovensiepen. "The UDE itself is playing zieme top stars for us and appointing them as new Professor:innen." However, it takes not only money to do research, but also time. And the members of the SFB use this time in their own way - successfully in the national league of universities - and it enables us to compete in the Champions League with our research. This also allows us to compete internationally.
- Hydrogen in Serial Production
20th August 2021,
Major Project for Sustainable Energy System. Read original article
A look inside the plasma facility at UDE: the glowing thing is the plasma that physicists Prof. Axel Lorke and Dr. Nicolas Wöhrl use to treat materials for electrolysis. © UDE/Nicolas WöhrlA major step towards a sustainable energy system has been taken: the nationwide hydrogen lead project H2Giga starts today. Among the 130 participants from science and industry are researchers from the University of Duisburg-Essen (UDE). The German Federal Ministry of Education and Research is funding the project with around 500 million euros over four years - more than 2.5 million euros will go to the UDE scientists.
The goal is clear: Germany should take a leading role in the field of hydrogen technology - and thereby increasingly harmonize climate protection and the economy. Hydrogen can be used to convert renewable electrical energy into chemical energy and thus make it storable. However, the production of hydrogen by electrolysis - the decomposition of water into hydrogen and oxygen - is currently still largely done by hand, with correspondingly high costs and low production capacity. This is where the H2Giga lead project comes in, by preparing and promoting the industrialized series production of water electrolysis.
The UDE scientists involved are members of Materials Chain and work in the PrometH2eus subproject - with very different focuses. The special feature of this combination, as project participant Prof. Doris Segets emphasizes, is that "three young people who are still in the early stages of their careers are in charge of such an important project. This is what distinguishes our team on site and the UDE."
For example, the subproject of physicists Prof. Axel Lorke and Dr. Nicolas Wöhrl is concerned with the targeted surface modification of materials in a plasma system. Metal and alloy materials are to be treated in such a way as to produce promising materials for electrolysis - either with higher electrochemical activity or greater stability. Both would make the applications more cost-effective. Meanwhile, chemist Prof. Corina Andronescu and her team are studying materials to identify those with high activity in oxygen formation from water. She wants to find out how the material structure influences the process of electrolysis. The subproject of process engineer Prof. Doris Segets is located toward the end of the process chain: She is investigating how the production of new electrode materials can be transferred from laboratory to industrial scale. Wöhrl as well as Segets and Andronescu use the laboratories at the NanoEnergieTechnikZentrum (NETZ) and thus even work together on site.
Further Information:
Prof. Corina Andronescu, Institute of Technical Chemistry, 0203 379 3442, corina.andronescu@uni-due.de
Prof. Doris Segets, Institute of Combustion and Gas Dynamics, 0203 379 8230, doris.segets@uni-due.de
Dr. Nicolas Wöhrl, Experimental Physics, 0203 379 3131, nicolas.woehrl@uni-due.de - Plasmas Facilitate the Production of Small Structures
17th August 2021,
Microsystem Technology.
“The future starts now, with the construction of dedicated research facilities at the border between basic and applied research,” says Professor Martin Hoffmann. © Damian GorczanyMaterials Chain member Martin Hoffmann explains why plasma processes are essential for microsystem technology and which opportunities they offer for eco-friendly manufacturing methods.
Plasmas are the tool of choice for microsystem technology. As electronic chips are getting smaller and smaller, structures can only be realized with dry, plasma-assisted processes. Wet chemical processes no longer work in these dimensions. During drying, small, movable structures are glued together by surface tension, just as two sheets of glass with a very thin film of water between them can hardly be separated. New materials such as glasses or 2D semiconductors require new processes for deposition and structuring.
The key is specially adapted plasmas. In addition, we need to significantly advance the methods for measuring the internal parameters of a plasma and the relevant process control in real time. This is the only way we can also achieve reproducible results in batch production. In addition, plasma processes offer resource-saving, environmentally friendly manufacturing methods with minimal material input – even when coating with new types of materials. This future begins now, with the construction of research facilities at the boundary between basic and applied research and cross-disciplinary cooperation to enable the use of innovative materials.
- Plasma Generators Control Catalytic Processes
10th August 2021,
Industrial Chemistry.
“In the future, catalysis, plasma and reaction engineering experts will be working hand in hand,” claims Professor Martin Muhler. © Damian GorczanyMaterials Chain member Martin Muhler from the Chair of Industrial Chemistry at Ruhr-Universität Bochum explains in what way plasmas are likely to affect chemical reactions in future.
In ten years, researchers will have understood the interactions between catalysts, which determine the speed of chemical reactions, and plasmas. This will facilitate the excitation of the plasma at atmospheric pressure in such a way that its properties accelerate the reactions on the catalyst surface in a controlled manner. As a result, chemical engineers will not only increase the turnover of the starting materials, but also the percentage of these materials that will be converted into the required product.
Therefore, the vision is that plasma generators will control catalytic processes. New compact plasma catalyst modules will be created, through which large gas flows can pass with little pressure drop. This will enable exhaust gas streams to be purified and other important industrial reactions to be carried out. In order for the modules to work in a resource-saving way, researchers still have to boost their energy efficiency. In future, catalysis, plasma and reaction engineering experts will work hand in hand to develop plasma catalyst modules. Computer-aided plasma, velocity and flow simulations will help to optimise them.
- How Cola Still Tingles After a Year
5th August 2021,
Polymers.
A capacitively coupled plasma source (CCP) for the generation of nanoparticles. The nanoparticles are embedded in composite layers for filter membranes to control selectivity for different gases. © Damian GorczanyA few nanometers of thin quartz-like coatings can multiply the shelf life of food, enable brilliant OLED TV pictures or separate gases from each other. When it comes to recycling, they can simply be neglected.
When you add energy to gases or gas mixtures, a plasma can be created, and inside it things go haywire: atoms turn into ions, free electrons whiz through space and collide with everything, some ingredients decay, other substances form anew. Depending on what is added to the starting material, plasmas can therefore be used to produce larger compounds. Hydrocarbons and silicon hydrogens are turned into long chains of molecules called polymers.
“If you want to etch with plasmas that tend to form polymers, it’s bad because the nanoparticles that form are a hindrance,” explains Professor Peter Awakowicz, holder of the Chair of General Electrical Engineering and Plasma Technology at RUB. But his team has taken advantage of the situation. If polymers are specifically made to form and deposit on the surfaces surrounding the plasma, they can be coated in a targeted manner. Thanks to this so-called Plasma Enhanced Chemical Vapor Deposition, or PECVD for short, it is possible, for example, to apply ultra-thin, gas-tight coatings to the inside of PET bottles, ensuring that the contents last longer, or to protect organic light-emitting diodes (OLEDs) from moisture so that the TV screens work for a long time. This and much more is only possible because the plasmas are cold and thus do not damage the PET bottle or other surfaces to be coated with heat. Only the fast electrons in the plasma are hot, and they do not damage the surfaces.
Making milk and medicines last longer
The glass-like coating of the plastic, which is only 20 to 30 nanometres thin, ensures that 10 to 100 times less gas escapes through the bottle. This extends the shelf life of a soda pop from the previous four weeks to about a year. The method is also of interest for the packaging of milk and other foods, as well as medicines and even microelectronic components.
“This type of coating is also environmentally friendly, because the tiny amount of material can simply be neglected during recycling,” explains Dr. Marc Böke from the Experimental Physics II department at RUB. Composite materials made of plastic and aluminum, such as Tetrapaks, are far more difficult to recycle because it is very difficult to separate the components.
Other applications of the PECVD method can be, for example, the coating of implants that grow into the bone better than conventional ones. There are also many microelectronic applications. For example, transistors can be deposited with ultrathin silicon dioxide films in plasma.
Oxygen tips the scales
The challenge lies in controlling the formation of the layers. “The layers should not only be ultra-thin, but also absolutely dense, gap-free and uniform,” explains Marc Böke. The adjusting screws for this are manifold. For one thing, it depends on the gas mixture. Atomic Oxygen is a particularly important player. Its proportion can be used to control, among other things, whether other additives evaporated into the plasma form inorganic layers, such as the glass-like silicon dioxide, or organic layers that have other interesting properties, such as giving surfaces greater biocompatibility or enabling gas separation.
The pressure at which the plasma is operated is also significant. Higher pressures and corresponding gases result in the coating of surfaces, while lower pressures are more likely to result in etching processes, which are central to all microelectronics (from cell phones to modern cars). Similarly, the geometry of the reactor and the choice of energy source influence what happens in the plasma and how it affects the surrounding surfaces. For example, an appropriate plasma can be ignited by microwaves, but also by inductively or capacitively coupled radio frequency. “In general, different sizes of plasma reactor are possible, up to the huge dimensions needed to coat entire window panes for high-rise buildings,” says Peter Awakowicz. These coatings serve to reflect infrared radiation that would otherwise cause it to get as hot behind them as in a greenhouse when the sun shines. But you can still see through it. With the sputtering of thin metal layers on foils used for this purpose, it is also possible to work in a feed-through process and thus coat many square metres.
Measurement techniques had to be developed
Only after the basic mechanisms of high-power pulsed sputtering (HiPIMS) and PECVD had been measured and understood in the first phase of the Collaborative Research Center SFB/TR 87 the research teams could get down to the business of implementing such large-area coatings. “We had to develop the appropriate measurement techniques in some cases,” Awakowicz recounts. “If you simply hold a measuring probe in the plasma, it may become coated itself and may lose its function,” he gives an example.
The researchers have gradually been able to fathom and perfect many aspects of the possible processes. For example, PET bottles are cleaned and activated before coating, also by means of plasma. But here, too, the surface of the bottle changes, which in turn influences the subsequent coating. Measurements of the particle flows during cleaning revealed what happens in the process: is wettability increased? And if so, how? Does the surface energy change? At what point in the treatment does the surface become roughened? “If the surface is too rough, you can no longer cover it evenly with an ultra-thin coating,” explains Marc Böke. If all these aspects are taken into account during cleaning and the process is run optimally, this has a considerable influence on the success of the subsequent coating: “We were able to increase the impermeability, which was initially a factor of 100 (depending on the substrate material), to a factor of 500 through the correct setting of the previous cleaning,” says Peter Awakowicz.
Keeping plasticizers away from food
Detailed knowledge of the processes in the plasma and the resulting coatings now also make it possible to coat stretchable films with gas-tight thin films. Thanks to an intervening buffer layer, Marc Böke’s team was able to increase the tolerance of the layer to the stretching of the film from originally about three to about six percent. This application is also of interest to the food industry, for example, as the dense coating prevents ingredients from the film, such as the dreaded plasticizers, from penetrating the food.
The latest application, which is currently being worked on, makes a virtue out of necessity: if one actually wishes for layers that are as dense and defect-free as possible, defects such as tiny pores in the coating are almost impossible to avoid. They allow the research teams to use plasma coating to develop non-swelling filter membranes that exhibit previously unknown properties. They can desalinate water or separate gases from each other, such as oxygen from CO2. “Normally, the more selective a membrane is, the lower its transmission, i.e. the more inefficient the process,” explains Marc Böke. “With plasma coating, however, we can control pore formation so that selectivity no longer comes at the expense of transmission or efficiency.” The researchers of the SFB/TR87 can simulate and tailor the polar properties of the membrane. This makes it easier for certain molecules to pass through the membrane. “Water molecules, for example, are made to give up their actual angle, practically flattening out and thus sliding through the pore,” Peter Awakowicz describes. “You couldn’t target something like that before.”
- Stroke Research without Animal Testing
26th July 2021,
.
Confocal laser scanning microscopy images of 3D organoids after 120 h cultivation time. The core of organoids consists of astrocytes covered by pericytes and an outer layer of endothelial cells. The overlay image of all channels represents the whole organoid.
© UDE/AK EppleWhen researching damage caused by strokes, there is no getting around them: mice. Their brains are used to simulate vascular occlusions and their consequences - until now: The future could belong to "mini-brains" from the laboratory. With them, a team of researchers from medicine and chemistry at the UDE wants to establish new methods in stroke research without animal testing. The German Federal Ministry of Education and Research (BMBF) is funding the recently launched project with 750,000 euros.
For the next three years, everything will revolve around 3D organoids in an in vitro process. The cell structures produced in the laboratory, which resemble organs and provide tissue for investigations, are not a new invention by the UDE researchers. "But we are applying this method to stroke research for the first time," says CENIDE member Prof. Dr. Matthias Epple from Inorganic Chemistry. Together with his colleague, Dr. Viktoriya Sokolova, and his colleagues from Essen University Hospital, biologist Prof. Bernd Giebel (Institute of Transfusion Medicine) and physician Prof. Dirk M. Hermann (Chair of Vascular Neurology, Dementia and Aging Research), Epple wants to optimize and validate the animal-free model. In this way, it should find its way into research as quickly as possible. "If we succeed, research will need up to 20,000 fewer mice per year," Hermann estimates. That's a good start, given that more than 200,000 mice are used for stroke research worldwide every year.
The three scientists and their teams have spent several years preparing the project, and they have already worked together on an interdisciplinary basis. Now it's time to get practical: the team cultivates three to six different cell types in the laboratory. The "mini-brains" will then be used to test which active ingredients pass the blood-brain barrier and what their effects are, including extracellular vesicles and ultra-small nanoparticles with different sizes and charges. "This drug discovery is an important step in the development of new drugs; it will help us develop a potential stroke therapy," Giebel explains.
The BMBF is deliberately pushing alternative methods research with its funding. If the UDE team is successful, there will not only be a publication at the end of the project, but also a workshop and a YouTube channel to raise awareness of the new approaches in stroke research without animals.
Further information:
Prof. Dr. Matthias Epple, Inorganic Chemistry, Tel. 0201/18 3-2413, matthias.epple@uni-due.de - Research Group Led by Dr. Marc Aßmann Finds Exotic Interactions in Semiconductors
23rd July 2021,
Publication in nature Communications.
Dr. Marc Aßmann's team has tailored two laser beams to precisely study the interactions of Rydberg excitons.
© Felix Schmale/TU DortmundA research team led by the group of Dr. Marc Aßmann from the Faculty of Physics at TU Dortmund University has investigated the extraordinarily strong interactions of Rydberg excitons in copper oxide in a transnational collaboration with partners from the universities of Rostock, Aarhus and Harvard. In the process, the group discovered a blockade effect between excitons that, with a size of several micrometers, appear like giants in the quantum mechanical system. The controllability of such effects is highly relevant for optical circuits and quantum information processing. The results were recently published in the prestigious journal Nature Communications.
Excitons are hydrogen-like bound states of negatively charged electrons and positively charged electron vacancies - called holes - in a semiconductor. They play an important role in fields as diverse as organic solar cells, photosynthesis and semiconductor lasers. Analogous to hydrogen, excitons also have excited states. Excitons in highly excited states, the Rydberge excitons, exhibit astonishing properties that are all the stronger the higher the quantum number of the excited state: For example, the volume of the twentieth excited state of an exciton is already 64 million times larger than in the ground state, while the polarizability, i.e. the sensitivity to external electric fields, is even 1.2 billion times larger. These properties make Rydberge excitons very interesting for precision sensing.
Investigations with tailored laser beams
Dr. Julian Heckötter investigated the interactions between several such Rydberge excitons in different states as part of his doctoral thesis, which was awarded the Wilhelm and Else Heraeus Dissertation Prize by the Dortmund Physics Faculty. To do this, he tailored two laser beams so that each beam produced a precisely defined Rydberge exciton state, and was thus able to precisely measure the interactions between the two states. In doing so, he was able to demonstrate a complex blocking effect. "We found that a sphere forms around each exciton in which no further excitons can be generated," says Dr. Marc Aßmann. "The excitons must maintain a certain minimum distance from each other, which can be several micrometers in size."
This also revealed a systematic asymmetry that depends on whether the effects are studied on a larger or a smaller exciton. Together with theorists Dr. Valentin Walther from Harvard, Prof. Thomas Pohl from Aarhus and Prof. Stefan Scheel from Rostock, this phenomenon could be elucidated. Detailed computer simulations showed that the cause lies in Van der Waals interactions. These are the same forces that are mainly responsible for geckos being able to walk along walls and ceilings.
The results of the interdisciplinary research team were recently published in the renowned journal Nature Communications. The project was funded in part by the joint German-Russian Collaborative Research Center TRR 160, which involves research institutions in Dortmund and St. Petersburg.
- NFDI-consortia FAIRmat and NFDI-MatWerk with ICAMS participation approved
19th July 2021,
Trending topic: science data management.
© NFDIThe FAIRmat and NFDI-MatWerk consortia receive funding for 5 years as part of the national research data infrastructure (German: NFDI). The initiatives of the national materials science community with involvement of the ICAMS researchers Thomas Hammerschmidt, Alexander Hartmaier and Godehard Sutmann at Ruhr-Universität Bochum aim to build an infrastructure for materials science data. The goal of both initiatives is to make materials data findable, accessible, interoperable and repurposable (FAIR) as the basis for a change in paradigm towards data-oriented materials research.
Go to NFDI for further information on the National Research Data Infrastructure initiative.
Further information on the FAIR Data Infrastructure for Condensed-Matter Physics and the Chemical Physics of Solids consortium can be found on the: FAIRmat website.
- Group Led by Prof. Sebastian Henke Develops Novel Responsive Materials
9th July 2021,
Publication in nature Communications.
Prof. Sebastian Henke teaches and conducts research at the Faculty of Chemistry and Chemical Biology at TU Dortmund University.
© Nikolas Golsch/TU DortmundA research team led by the group of Prof. Sebastian Henke from the Faculty of Chemistry and Chemical Biology at TU Dortmund University, in cooperation with partners from Ruhr-Universität Bochum, has investigated the extraordinary responsive behavior of porous metal-organic framework compounds. Depending on their environmental conditions, these can crumple up and unfold again in a similar way to a piece of paper. The findings, which are highly relevant for their application in energy storage or molecular separation, for example, were recently published in the renowned journal Nature Communications.
Metal-organic frameworks (MOFs for short) are synthetic materials. They are composed of organic and inorganic molecules in a modular fashion and exhibit a porous, open structure. Some MOFs also exhibit responsive properties, meaning that they change their crystal structure depending on environmental conditions. For example, when the chemical composition of the surrounding atmosphere is varied or mechanical pressure is applied, the size and shape of the pores change. This responsiveness enables MOFs to store gases very efficiently or to separate molecules from one another, among other things.
PhD student Roman Pallach from the group of Prof. Sebastian Henke has now discovered a new form of responsivity in MOFs: Through targeted chemical modification of the organic MOF building blocks, the networks no longer switch back and forth between two crystalline - i.e. ordered - states, but between an ordered and a very complex, disordered state. The modified building blocks generate competing interactions within the network structures, so that the disordered state is preferred in the absence of guest molecules - for example, stored gases - in the pores.
"If we remove the guest molecules from the pores, the network is frustrated, so to speak, and can only fold up in a disordered way," says Prof. Sebastian Henke. "Folding together while maintaining order is not possible with these MOFs."Investigation with X-ray scattering methods
In cooperation with Dr. Julian Keupp of Prof. Rochus Schmid's group at Ruhr-Universität Bochum and members of Prof. Rasmus Linser's group at the Department of Physical Chemistry at TU Dortmund University, the scientists investigated the responsive behavior of the MOFs theoretically and experimentally, gaining deep insights into the structure and temperature-dependent dynamics of the disordered state. In addition to computer simulations and spectroscopic techniques, they used sophisticated X-ray scattering methods at the synchrotron radiation source DELTA at TU Dortmund, the German Electron Synchrotron (DESY) in Hamburg and the Diamond Light Source (near Oxford, UK).
The results of the interdisciplinary research team were recently published in the renowned journal Nature Communications. The project was funded, among others, by the joint Cluster of Excellence RESOLV of the Ruhr-Universität Bochum and the TU Dortmund University.
To the publication:
R. Pallach, J. Keupp, K. Terlinden, L. Frentzel-Beyme, M. Kloß, A. Machalica, J. Kotschy, S. K. Vasa, P. A. Chater, C. Sternemann, M. T. Wharmby, R. Linser, R. Schmid, S. Henke, Nat. Commun. 2021, 12, 4097: Frustrated Flexibility in Metal-Organic Frameworks. DOI: 10.1038/s41467-021-24188-4
- Cooperation for International Top-level Research
8th July 2021,
UA Ruhr Seals Cooperation.
The three rectors are pleased about the funding notification from the state (from left): Prof. Ulrich Radtke (UDE), Prof. Manfred Bayer (Tu Do), Prof. Axel Schölmerich (RUB).
© Michael SchwettmannThe expansion of top international research at the University Alliance Ruhr (UA Ruhr) can begin: on July 7, 2021, the rectors of Ruhr-Universität Bochum, Technische Universität Dortmund and the University of Duisburg-Essen signed a cooperation agreement to establish the Research Alliance Ruhr in the presence of Science Minister Isabel Pfeiffer-Poensgen. This means that the four research centers and the college can now begin to attract top international scientists for their forward-looking research projects. For the start-up phase, the state government is providing up to 75 million euros from Ruhr Conference funds for this purpose until 2024.
"With the establishment of the Research Alliance Ruhr, we are bundling the top university research of the universities of Bochum, Dortmund and Duisburg-Essen in forward-looking research fields. In the 1960s, the establishment of the Ruhr universities played a key role in driving forward the structural transformation of the Ruhr region. The cooperation now concluded will create a new, highly innovative university association that meets the highest scientific excellence criteria. In this way, we as the state government, together with the universities, want to raise the international appeal of the Ruhr region as an excellent science region to a new level," says Science Minister Isabel Pfeiffer-Poensgen.
Ruhr region as a globally networked innovation region
North Rhine-Westphalia's Minister for Europe, Dr. Stephan Holthoff-Pförtner, who is in charge of the Ruhr Conference, and State Secretary Dr. Mark Speich, who as State Secretary is driving the thematic forum "Ruhr as a globally networked innovation region," said in a joint reaction: "With the agreement concluded today, the participating universities are exemplifying the spirit of the Ruhr Conference: Collaboration across municipal and institutional boundaries to make world-class possible. This spirit of cooperation and excellence should also be a model for us in other fields of action. The future is not created in silos."
"With the Research Alliance Ruhr, we are creating a new joint research institution to bundle the strengths of the three universities and further expand them in a targeted manner," emphasizes UDE Rector Prof. Dr. Ulrich Radtke. His colleague from Bochum, Prof. Dr. Axel Schölmerich, adds: "With the new structure, we will be even more successful in the future in attracting top people from all over the world to the Ruhr region and increasing its international appeal." "The region will benefit from innovative ideas from research," adds TU Rector Prof. Dr. Manfred Bayer. "Change through science has a tradition here and will continue to drive the metropolitan region forward in the future."
Urgent questions for the future
Research focuses on pressing future issues such as the holistic health of people and the environment, sustainability and renewable energy, and trust in digital systems. The four Research Centers "One Health - from Molecules to Systems," "Chemical Sciences and Sustainability," "Future Energy Materials and Systems," and "Trustworthy Data Science and Security" conduct research on these issues. The College for Social Sciences and Humanities, on the other hand, offers an open-topic platform for international exchange in the humanities and social sciences.
Over the next four years, the five units will be set up by a total of 17 founding directors in consultation with the rectorates of the three universities. They will determine the orientation of new research areas to be filled, which will be linked to the universities through joint appointments in consultation with the faculties. The positions will be financed by the additional state funds. This approach will enable the Research Alliance Ruhr to develop flexibly, grow in line with demand and make optimal use of the potential of the joint research area. Full operation is to be achieved successively by 2025, for which the state has promised an annual budget of around 48 million euros.
Green light from the expert panel
The idea of establishing cross-location research centers with international appeal in the Ruhr region had won out in an open ideas competition held as part of the Ruhr Conference in 2019. In November last year, the state government had allocated a total annual budget of 75 million euros for 2021 to 2024. In March 2021, a panel of experts assembled by the Science Council finally gave the green light for the UA Ruhr concept. Based on the cooperation agreement now concluded, the legal structure of the Research Alliance Ruhr is to be formulated by the end of 2021 in accordance with the possibilities offered by the Higher Education Act of North Rhine-Westphalia.
Further information:
Dr. Hans Stallmann, Coordinator UA Ruhr, Tel. 0234/32-27892, hans.stallmann@uaruhr.deTo the website: https://www.uaruhr.de/researchallianceruhr/index.html.de
- Using Plasma and Electrolysis for CO2 Recycling
7th July 2021,
Underwater Plasma.
The ignition of plasma under water
© Damian GorczanyPlasmas in liquids have long been used in water purification and wound treatment. Now, they are to improve the efficiency and service life of an electrolysis cell used for C02 conversion.
The plasma ignites with a bright flash and tears through the water for a few billionths of a second. Dr. Katharina Grosse from Collaborative Research Centre 1316 “Transient atmospheric plasmas – from plasmas to liquids to solids” (RUB) takes spectacular pictures that show the ignition process of plasma under water at high temporal resolution. Delivering the first data sets with very high temporal resolution, the researcher supports a hypothesis on the ignition of these plasmas: there is not enough time in the nanosecond range to form a gas environment. The nanosecond plasma ignites directly in the liquid. The particles created during ignition can interact efficiently with catalytic surfaces.
But how does the plasma ignite in these short time scales? What happens afterwards? Which substances are produced? And how is this ignition in the liquid possible in the first place? In her doctoral thesis, physicist Grosse explores these very questions. To this end, she applies a high voltage to a hair-thin electrode immersed in water for ten nanoseconds. The strong electric field thus generated leads to the ignition of the plasma. Using high-speed optical spectroscopy in combination with modelling of the fluid dynamics, the Bochum-based researcher is able to predict power, pressure and temperature in these underwater plasmas and, consequently, to explain the ignition process and plasma development in the nanosecond range.
Hotter than the sun
This is what she has observed: at the time of ignition, extreme conditions exist in the water. For a short time, pressures of many thousands bar are created; this corresponds to or even exceeds the pressure at the deepest point in the Pacific Ocean, as well as temperatures of many thousands degrees, similar to the surface temperature of the sun. “In addition, a power of several 100 kilowatts is consumed in the plasmas for a short time, which more or less equals the connected load of several single-family houses,” explains Professor Achim von Keudell, Grosse’s doctoral supervisor and head of the Institute for Experimental Physics II.
To achieve these measurement results, a complicated setup is necessary, which Katharina Grosse spent roughly a year on developing: “The electromagnetic interference is very strong and affects all measurement electronics. We had to build a large metal cage around the plasma chamber to bypass this source of interference. Another difficulty was to ensure the simultaneity of spectroscopic measurement and camera recording.”Rendering plasma development visible
The tinkering has paid off: it is now possible to observe the plasma development very precisely. The recordings call into question the theory that has been common so far. Until now, this theory assumed that a high negative pressure difference forms at the tip of the electrode, which leads to the formation of very small cracks in the liquid with expansions in the nanometre range, in which the plasma can then spread. “It was assumed that an electron avalanche forms in the cracks under water, enabling the ignition of the plasma,” says von Keudell. However, the images taken by the research team from Bochum suggest that the plasma is “ignited locally within the liquid,” explains Grosse.
Tunnel effect under water
In her attempt to explain this phenomenon, the physicist uses the quantum-mechanics tunnel effect. This describes the fact that particles are able to cross an energy barrier that they should not be able to cross according to the laws of conventional physics, because they do not have enough energy to do so. “If you look at the recordings of the plasma ignition, everything indicates that individual electrons tunnel through the energy barrier of the water molecules to the electrode, where they ignite the plasma locally, i.e. precisely where the electric field is highest,” says Grosse. This theory has a lot going for it and is the subject of much discussion among experts. Subsequent experiments with negative pulses are to support Grosse’s tunnel theory.
Water is broken down into its components
The ignition process under water is as fascinating as the results of the chemical reaction are promising for practical applications. The emission spectra show that, at nanosecond pulses, the water molecules no longer have the opportunity to compensate for the pressure of the plasma. The plasma ignition breaks them down into their components, namely atomic hydrogen and oxygen. The latter reacts readily with surfaces. And this is precisely where the great potential lies, explains physicist Grosse: “The released oxygen can potentially re-oxidise catalytic surfaces in electrochemical cells so that they are regenerated and once again fully develop their catalytic activity.”
Underwater plasmas and electrolysis
How exactly is this going to be achieved? Can plasma and electrolysis be combined? RUB PhD student and chemist Philipp Grosse is looking for answers to these questions at the Fritz Haber Institute of the Max Planck Society in Berlin. “Electrochemical cells,” he explains, “help, for example, to reduce, recycle and convert carbon dioxide into useful chemicals. This requires a catalyst. However, during the electrochemical process, the catalytic surfaces wear out and lose their catalytic capabilities.” This is where the underwater plasmas studied by Katharina Grosse could provide a remedy and be used for material conversion at the electrode-liquid interface.
The brother and sister team intends to find out in what way underwater plasmas can be used in the electrolysis of chemical substances. How can the plasmas support electrolysis by changing the liquid and the electrode surface? How does plasma interact with the electrochemical cell? For this purpose, Katharina Grosse is setting up her experimental setup in Berlin, where her brother Philipp has been conducting research for two years. Instead of water, they use electrolytes as liquids, and a catalytic surface is built directly into the plasma chamber. The Grosses decided to use copper oxide in the form of nanocubes as a catalyst. These are nanometre-sized copper oxide cubes that are used as a catalyst for CO2 reduction. They then apply a high voltage to the electrode for a few microseconds. A plasma ignites. The changes observed in the copper cubes suggest that the oxygen produced by the plasma ignition activates the copper oxide. The initial measurements imply that the extreme plasma is indeed able to re-oxidise the copper cubes and thus regenerate the catalytic surface. Once the catalyst is ready for use again, the electrochemical cell should also work, and with it the CO2 reutilisation process. This would allow CO2 to be continuously converted into other products in industrial plants; the cycle would thus be closed.
The dream of an infinite electrochemical cell
In Bochum and Berlin, the researchers are already dreaming of an infinite electrochemical cell in which electrochemical processes alternate with plasma ignitions. But the Grosses still have a long and complicated way ahead of them. The greatest challenge at present is to combine the physical with the chemical structure so that plasma ignition and electrolysis can take place simultaneously.
The future of plasma technology
Should this succeed, it would be a “milestone, a technology with a lot of potential,” stresses von Keudell. The chemical industry is very interested in such a plasma process, according to the spokesman for the Collaborative Research Centre: “They have high hopes for the electrification of the chemical industry.” The advantages of plasma technology: it takes up little space, and the electrical energy can support the conversion of chemical substances at the push of a button.
Original publications
- Katharina Grosse, Marina Falke, Achim von Keudell: Ignition and propagation of nanosecond pulsed plasmas in distilled water – Negative vs positive polarity applied to a pin electrode, in: Journal of Applied Physics, 2021, DOI: 10.1063/5.0045697
- Katharina Grosse, Volker Schulz-von der Gathen, Achim von Keudell: Nanosecond pulsed discharges in distilled water: I. Continuum radiation and plasma ignition, in: Plasma Sources Science and Technology, 2020, DOI: 10.1088/1361-6595/aba487
- Achim von Keudell, Katharina Grosse, Volker Schulz-von der Gathen: Nanosecond pulsed discharges in distilled water-Part II: line emission and plasma propagation, in: Plasma Sources Science and Technology, 2020, DOI: 10.1088/1361-6595/aba4b9
- Transforming Climate Killers into Raw Materials via Plasma Technology
1st July 2021,
Non-thermal Plasmas.
Non-thermal plasma could in future be used for the targeted purification and treatment of metallurgical gases.
© Damian GorczanyCold plasmas and plasma catalytic processes could be used to purify and treat metallurgical gases in the steel industry.
Hydrogen, oxygen, carbon monoxide, carbon dioxide, methane – the steel industry releases a veritable cocktail of gases every hour. But how can these metallurgical gases be purified? This is where the research of Professor Peter Awakowicz from the Chair of Electrical Engineering and Plasma Technology and Professor Martin Muhler from the Lab of Industrial Chemistry comes in. The interdisciplinary research team at RUB studies how non-thermal plasma can be used for targeted cleaning and processing the metallurgical gas mixture. In the Carbon2Chem joint project funded by the German Federal Ministry of Education and Research (BMBF), in which both researchers have been involved since 2016, they are testing their innovative plasma technology on real gases. “The combination of a basic research project in Collaborative Research Centre 1316 and an application-oriented BMBF project has been a long-held dream of both of us that we can now fulfil,” says Awakowicz.
In sub-project L3 of Carbon2Chem, in which the RUB researchers are involved, the specific issue is pre-cleaning, the removal of oxygen from the coke oven gas. “This sounds simple, but it is tricky in detail,” explains research chemist Muhler. According to him, it is an intricate art to remove the oxygen from the predominantly hydrogenous coke oven gases. Traditional methods of exhaust gas purification, such as pressure swing adsorption, would not work if there was too much oxygen. The high chemical reactivity of oxygen would trigger dangerous gas reactions under normal pressure, such as an oxyhydrogen explosion. This is why Awakowicz and Muhler rely on pre-cleaning using plasma technology with cold plasma. How does it work? What makes non-thermal plasma so special? And how is it generated?
Innovative Technology for gas purification with cold plasma
Cold plasmas, or non-thermal plasmas, are plasmas in which the temperatures of ions, electrons and neutral particles vary. “The temperature of the electrons is high in these plasmas, while the temperature of the other gas particles is comparatively low,” explains Awakowicz. Since the plasmas are in thermal non-equilibrium, they are also often called non-equilibrium plasmas. They have an advantage with regard to gas purification processes: The ignited, cold plasma can be used for gas treatment without causing a significant increase in the temperature of the gas.
However, producing cold plasma is not easy. “The difficulty lies in supplying the gas with just enough energy so that the light electrons are accelerated and thus become hot, but the temperature of the large, heavy neutral particles and ions hardly changes,” explains Awakowicz. The research team from the Chair of Electrical Engineering and Plasma Technology has succeeded in producing precisely this state of non-thermal plasma in the purpose-built plasma reactor: The electrons become several tens of thousands of degrees Celsius hot, while the gas temperature of the entire plasma increases to barely more than room temperature.
“To achieve and understand this state, complex plasma diagnostics were necessary. We had to repeatedly readjust the individual parameters, such as the geometry and materials of the electrodes, the voltage amplitude and frequency, and associated with this the input power. Then the fundamental plasma parameters such as the electron density, the distribution function of the free electrons, but also the gas temperature had to be determined in order to optimise everything,” as Awakowicz describes the challenges.While the team led by electrical engineer Awakowicz was fine-tuning the parameters for producing the cold plasma, the chemical researchers led by Muhler were analysing the chemical reactions triggered by the plasma discharge. It turned out that the cold plasma is so reactive that it animates the oxygen contained in the coke oven gas to react with hydrogen, so that water is formed. The gas mixture is freed from oxygen and is thus ready for further purification processes.
Waste gas purification on an industrial scale
What Awakowicz and Muhler have fundamentally researched in the RUB laboratory is being applied to specific gas mixtures in the steel industry in the BMBF Carbon2Chem project. In the first project phase from 2016 to 2020, the researchers already provided proof of feasibility: Their plasma technology can be applied to these specific metallurgical gases. In the second funding phase from 2020 to 2024, the technical processes will now be further validated and scaled up for industrial application from 2025.
Scale-up in the Carbon2Chem pilot plant
The relevant experiments take place on an area of 3,700 square metres in the pilot plant in Duisburg. The pilot plant was built in 2018 adjacent to the thyssenkrupp Steel Europe site and means that Carbon2Chem’s experiments can be conducted under industrial conditions. “The real exhaust gases are routed to the pilot plant site, where they are available to us,” explains Muhler. “We now have to show that our plasma system can operate with the real gases – on a much larger scale, of course. The reactor should be able to purify more than fifty times the amount of gas,” as he outlines the challenge. At RUB, the researchers have so far worked with small gas flows of ten litres per minute in the lab; at the pilot plant, they are dealing with flows with a much larger volume of 500 litres per minute and more. “A spectacular project, since the dimensions are so huge,” point out Awakowicz and Muhler.
Industrial implementation planned in 2025
The commercial implementation of the gas purification plant is scheduled for four years from now. “The final step, scaling up from tenfold to one hundredfold, will be an effort,” Awakowicz suspects, adding: “As researchers, we will have to hand over the baton to industry at some point.”
- Simulating Atoms and Fractions of a Second
28th June 2021,
Humboldt Award Winner Comes to UDE.
Graphical representation of a bursting gold nanoparticle excited by ultrafast laser. The colors reflect the sizes of the resulting fragments: around 3 nm (red), around 1 nm (blue).
© ZhigileiHis world is picoseconds - trillionths of seconds; too short for atomically resolved experiments: Professor Leonid Zhigilei is a materials scientist at the University of Virginia (USA). He was awarded the Humboldt Research Award for his calculations on the production of nanoparticles. He will spend his associated research stay in Technical Chemistry I at the University of Duisburg-Essen (UDE). The focus will be on materials for catalysis.
Catalysts make our high standard of living possible, and an energy turnaround would be inconceivable without them: For example, they are essential in fuel cells, enable the green production of hydrogen and also its conversion into storable chemicals as energy storage. For this purpose, catalysts have so-called "active sites": millions of tiny pores in the material into which starting materials migrate. There, they are converted into a desired product - without a catalyst, this would happen more slowly, with more energy input or simply not at all. Therefore, the active sites must be easily accessible and not blocked by foreign molecules.
Such pure nanoparticles for catalyst materials can be produced by high-energy laser pulses, as is done by the Technical Chemistry I team at UDE. To further understand these processes and improve them on the basis of this, it is necessary to be able to observe the individual steps - but this is not possible even with high-tech methods in experiments; they happen too quickly.
Leonid Zhigilei, on the other hand, simulates these steps at the atomic level and can calculate the ultra-short time scales: "We approach theory and experiment together. This way, my simulations can reveal both dead ends and promising changes in advance."
Zhigilei is already collaborating with the Technical Chemistry I team led by Professor Stephan Barcikowski; as soon as the situation allows, he will spend extended periods of time in the group as a guest. "We do research in different fields, and that's what makes the collaboration so fruitful," says Zhigilei, explaining his decision to come to UDE with the Humboldt Research Award. "We ask each other questions that the other would not have thought of."
The Humboldt Research Award is given to internationally leading researchers from all disciplines from abroad. It recognizes their previous work and enables them to spend several months conducting research at a scientific institution in Germany.
Further information:
Prof. Dr.-Ing. Stephan Barcikowski, Technical Chemistry I, Tel. 0201/18 3-3150, stephan.barcikowski@uni-due.de - Gottschalk-Diederich-Baedeker Prize
14th June 2021,
Thinking Along with Industry and Society.
© UDE/Frank PreußThis year, the Gottschalk-Diederich-Baedeker Prize goes to Prof. Dr. Doris Segets. The 38-year-old expert in process engineering of electrochemical functional materials at the UDE is being honored for her scientific achievements and her commitment to bringing research achievements to industry. The prize is endowed with 5,000 euros and is awarded by the Essen-based G. D. Baedeker Foundation.
The aim of the prize is to make visible the research achievements of the UDE and their benefits for society, especially in Essen and the Metropole Ruhr. Prof. Doris Segets is predestined to be the prize winner. She works at the Center for Nanointegration (CENIDE) in the NanoEnergieTechnikZentrum (NETZ) and in close cooperation with the Center for Fuel Cell Technology (ZBT) - both in basic research and on the practical challenge of transferring processes to large dimensions. Together with her team, she is looking for suitable processing methods for industrial production. Nanomaterials are particularly suitable for technologies in energy storage due to their large surfaces "We want to understand and improve the entire process chain from the production of nanomaterials to the finished layer for batteries or fuel cells."
Before moving to the Ruhr region, Segets conducted research at the Friedrich Alexander University of Erlangen-Nuremberg, where she studied chemical and bioengineering, earned her doctorate in 2013, and then headed the "Nanoparticle Processing" research group as a postdoc."It was not only her scientific work, which has already won many awards, that convinced the jury. She additionally scored points for her ability to establish and maintain networks with partners at the university, transfer-oriented research institutions, and especially with small, medium-sized companies and industrial partners. Equally impressive is Segets' commitment to young scientists, whom she promotes intensively," said Martin Sutter, board member of the G.D. Baedeker Foundation. "We are very pleased to be able to honor such an outstanding scientist."
A date for the award presentation by the patron, the mayor of Essen, has not yet been set.
Further information:
Prof. Dr. Doris Segets, Process Engineering of Electrochemical Functional Materials, Tel. 0203/37 9-8230, doris.segets@uni-due.de - Nanoparticles Available at the Speed of Light
14th June 2021,
START-UP transfer.NRW project.
Current prototype of the compact fully automatic machine (dimensions: L 53 cm, W 41 cm, H 50 cm) for the production of colloidal nanoparticles. Designed at Projekter Industrial Design.
© Projekter Industrial Design GbR (Duisburg)Producing colloidal nanoparticles quickly, easily and reliably with your own laboratory machine. Two researchers from the University of Duisburg-Essen are making this possible using innovative laser technology. With their automated machine, they want to accelerate nano R&D worldwide.
Colloidal nanoparticles have unique properties that are not known from any other class of materials. In the last few decades, research has therefore witnessed a veritable hype surrounding these small particles, which has led to countless new applications and products in various fields of application. Particles are used in important technologies for the energy transition, are being tested in cancer diagnostics and are creating new functional materials, for example for additive manufacturing.
One product already known on the market that would not exist without colloidal gold nanoparticles is the pregnancy test. The test exploits the good biofunctionalizability of the gold particles, but also their characteristic red to violet color. As a nanoparticle, the metal, which is actually yellow, appears in unusual colors due to a special interaction with light called surface plasmon resonance. The actual color depends on the size of the particles. Gold nanoparticles are therefore optimal biosensors. Silver nanoparticles interact with light in the same way, but appear yellow. Their field of application, however, is not the detection of biological substances, but the control of microbes. For this purpose, the particles are embedded in coatings or textiles to give them antimicrobial properties. The optically less special platinum nanoparticles are excellent catalysts and are used, for example, in fuel cells.
There are countless other applications for nanoparticles of various materials. Many of them are still in their infancy and others have not even been discovered yet. In fact, research and development based on colloidal nanoparticles is lengthy. With current manufacturing methods, the process development for synthesizing a new colloid can take months. In addition, it requires skilled personnel and specialized equipment, which is not standard equipment in some application fields. The alternative supply via mail order is easier, but logistically not optimal. Colloids are metastable and therefore rather unsuitable for a supply with high logistic effort. Particle properties change over time and quality variations are the rule.
Manufacturing the colloids at the place and time of further processing offers the better supply. However, one needs to simplify the synthesis to make it accessible to every researcher and developer. That's where the AutoProNano team comes in. Bessel and Waag, two researchers from the University of Duisburg-Essen combine all synthesis steps in a fully automated machine. In this way, they reduce the complexity of colloid production for the user to just a few inputs on the touch display. The high degree of automation even makes operation self-explanatory and enables highly reproducible colloid quality, which is completely independent of the operator.
The compact laboratory automat produces nanoparticles at the speed of light. This is not quite correct, but the energy source of the synthesis is actually a laser system. Laser pulses of a few nanoseconds in length and of high intensity break down solids into nanoparticles in the automated machine. The particles are directly captured by a liquid and are then present as a colloid. In principle, any material can be processed into nanoparticles, and the liquid can also be
liquid can also be varied within certain limits. The material is changed by exchanging a practical capsule, similar to a printer. The two founders will recycle used capsules with their future venture.
Bessel and Waag are currently developing their prototype to market maturity in a START-UP transfer.NRW project with funding from the European Regional Development Fund. The development of the laboratory automat is scheduled to be completed by the end of 2021. At that time, the researchers also want to officially spin off from the university. The laboratory automaton should then be available on the market at the beginning of 2022. Until then, the prototype will already be used in research collaborations with various public institutions and companies. The future founders are already well networked through their university and have gained many new contacts in the HIGH-TECH.NRW Accelerator. Nevertheless, they are always on the lookout for new cooperation partners and welcome any contacts.
Bessel and Waag are already thinking one step ahead. Their automated machines should not only improve the supply of colloidal nanoparticles to R&D, but also to industrial producers. The good scalability of the continuous synthesis technique makes the consistent development of industrial automats possible. Scaling is at the top of the further development agenda.
Further information & editorial office:
Dr. Friedrich Waag, AutoProNano / Technical Chemistry I and CENIDE, UDE, 0201 183-3750, friedrich.waag@uni-due.deProject website: www.autopronano.eu
- DECHEMA Award for Chemical Engineer
31st May 2021,
.
© UDE/Frank Preuß"In the list are the teachers of my subject who have shaped the field. I still have to get used to the fact that my name is now also on it," says junior professor Dr. Doris Segets. The engineer from the Center for Nanointegration (CENIDE) at University of Duisburg-Essen will be awarded the DECHEMA Prize* for her groundbreaking work in process engineering. It will be presented on July 5 at the Duisburg campus.
The climate crisis has turned a rather academic question into a highly topical, practical research issue within the past ten years: How do we manage to transfer new materials that work excellently in the laboratory, for example for batteries or fuel cells, into industrial applications?
Chemical and bioengineer Doris Segets works at the NanoEnergieTechnikZentrum (NETZ) at the interface between research and industry: "I make sure that a development becomes practically usable." After all, suitable technologies and scaling methods for new materials are still lacking. After all, what works on a laboratory scale often looks quite different on an industrial scale - and is often not cost-effective either.
Structure determines function
The new classes of materials discovered in recent years often consist of tiny particles with extremely large surface areas. Here, phenomena that take place at these very interfaces are crucial. "The biggest challenge is the distributed properties," says the engineer. "In any particle-based application, particles are made of different materials, and they also differ in shape, size and surface properties." This is critical for function as well as handling, and makes processing new materials complicated.
For this groundbreaking work on the development of a process technology for ultrafine particles, Doris Segets now receives the highest scientific award that DECHEMA has to bestow. The jury particularly praised the creativity and versatility with which the researcher is opening up new fields of application for these materials.
"For a long time, the prize would rather have gone to someone who actually develops new materials as well," Segets surmises. "What I'm doing is basically the next step. Because it's been realized: here you can't get any further by trial and error, you have to understand the fundamental processes and mechanisms."
* The DECHEMA Prize has been awarded annually since 1951. It is endowed with €20,000. The DECHEMA Society for Chemical Engineering and Biotechnology awards it to young scientists for outstanding research work in technical chemistry, process engineering, biotechnology and chemical apparatus engineering. Doris Segets will receive the award on July 5 at the Duisburg campus. Participation via stream is possible.
Zum DECHEMA-Interview
Zum 2. Teil des DECHEMA-Interviews
Further information:Prof. Dr. Doris Segets, Process Engineering of Electrochemical Functional Materials, Tel. 0203/37 9-8230, doris.segets@uni-due.de
- New degree program in materials science
27th May 2021,
In the study the hands also get dirty sometimes. Read original article
Alexander Hartmaier introduces the new Materials Science program. © RUB, MarquardThe combination of natural science and engineering issues characterizes the study of materials science at Ruhr-Universität Bochum.
Starting in the winter semester 2021/22, RUB is expanding its range of courses and offering the bachelor's degree program in materials science for the first time. "We are training future engineers who can develop, test and improve materials," reports Prof. Dr. Alexander Hartmaier, who heads the Chair of Materials Mechanics.
Combining theory and practice
In the first two years of study, students learn the basics of mathematics, physics, chemistry, materials science and materials engineering. The focus is on linking practice and theory: "From the first semester, our students will apply their theoretical knowledge in practical courses and also get their hands dirty when, for example, they harden, break or deform materials in a controlled manner," says Hartmaier.From the fifth semester onwards, students can choose between the specializations "Modeling and Simulation" and "Experimental Materials Science". Afterwards, they can choose a master's degree in "Material Science and Simulation" or mechanical engineering at the RUB, or they can take the step into the professional world. "Our graduates have very good prospects of finding a job in the materials industry in the Ruhr region, with which we have long had close links. They can be employed in quality control, product development or analysis," says Hartmaier.
Wide range of job prospects
With their skills, they will also be able to address sustainability issues, such as recycling plastics, or make further advances in medical technology. Here, for example, materials scientists are helping to refine stents made of shape memory alloys for heart operations, which are inserted folded into the vein and then unfold by themselves as they heat up to body temperature.The materials science program is open-admission; interested students can enroll for it around mid-August and begin their studies on October 11, 2021.
- Working on the Computer of the Future
26th April 2021,
EU Funds Two International Physics Projects.
© Nikolas Golsch/TU DortmundThe working group led by experimental physicist Professor Mirko Cinchetti from TU Dortmund University is to receive EU funding of almost a million euros for research into new technologies that could in future revolutionize computer processors and data storage media.
In the framework of its “Horizon 2020” program, the EU has approved research funds of over € 6.5 million for two international research projects involving Dortmund physicist Professor Mirko Cinchetti. Of this total sum, his research group at TU Dortmund University will receive more than € 900,000.
The two projects have been allocated funding in the FET Open category, which is open to all topics and makes funds available for high-risk scientific and technological research projects at a very early stage. The call, as it says, is particularly aimed at research projects with “radically new ideas” for “breakthrough technologies”.
Research on new technologies for computer processors and data storage media
“With the SINFONIA and INTERFAST research projects, we want to explore potential applications of molecular systems in the field of electronics and computer technology,” explains Professor Cinchetti. The objective of the projects is to advance existing concepts from basic research in the direction of possible applications. In this way, they could later be used in commercially available electronics with the help of technology multinationals.
The work conducted by Professor Cinchetti and his international colleagues within SINFONIA could contribute to a more efficient technology superseding – in the long term – semiconductor technology, which has formed the basis for the processors in our computers for many decades. The research team plans to produce hybrid structures from molecules and antiferromagnets, which can be used as logical computing circuits in what is known as magnonics. In comparison to conventional semiconductor technology, magnonics circuits have the advantage that no electrical current flows through them. As a consequence, they have a very low energy demand, generate hardly any heat, and can work substantially faster. This should facilitate the development of considerably more powerful processors.
Within the INTERFAST project, the researchers are also endeavoring to develop the foundations for a new data storage technology. Compared to conventional storage methods, this should be characterized by a significantly higher information density.
Extensive international collaboration
Due to the large number of proposals, the probability of receiving FET Open funding was under 10 percent – only 58 of the 902 projects for which a proposal was submitted were awarded funding.
Apart from TU Dortmund University, numerous other research institutions from Italy, Spain, France, Ireland, Slovenia, and the United Kingdom are participating in the two projects. Their joint work within SINFONIA started in April 2021 and is to last four years. Professor Cinchetti’s research group has € 500,000 at its disposal for this. Then, one month later, May 2021 will see the start of INTERFAST, which is planned as a three-year project. The researchers from Dortmund will receive a further € 400,000 for this project.
Further information on the research projects: SINFONIA INTERFAST
Contact for further information: Prof. Dr. Mirko Cinchetti Tel.: +49 231 755 5438 Mail: mirko.cinchetti@tu-dortmund.de TU Dortmund Experimentelle Physik VI Fakultät Physik
- Atomic Layer Pushes Surface Steps Away
26th April 2021,
Synthesis of Large-Area 2D Material.
Image sequence showing the evolution from the pure iridium surface (left, pink) to the fully borophen-covered surface of the sample (right, yellow-orange).
© UDE/PetrovićElbow mentality in a two-dimensional material: This has recently been discovered by an international team led by the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE): The physicists succeeded in creating boron layers with a height of a single atom. While growing, the material simply pushes interfering steps on the substrate out of the way. The team published its results in the scientific journal ACS Nano.
The team led by UDE’s Prof. Michael Horn-von Hoegen aims at producing the thinnest possible layer of boron, so-called borophene, since it promises properties that could enable the construction of two-dimensional transistors. The molecular beam epitaxy used for this purpose until now results in domains that are far too small. For more precise investigations and for use in technology, however, larger areas are needed.
With their newly developed method of "segregation-enhanced epitaxy", the team uses borazine gas and an iridium substrate. The essential components of borazine are boron and nitrogen atoms that are arranged in a hexagonal honeycomb structure. By heating the iridium sample in a borazine-containing environment, the boron molecules attach themselves to the surface, followed by the evaporation of the nitrogen. Above 1100°C, the boron moves into the iridium, because at such high temperatures the iridium can absorb additional boron atoms like a sponge – up to a quarter of its own volume. When the system has cooled down, borophene – the single-atom layer of boron – precipitates on the surface of the iridium crystal. In the process, it does not grow beyond surface steps of the underlying crystal but pushes them away in all directions to form areas as large as possible.
Next Step: Detachment
Experts from the Interdisciplinary Center for Analytics on the Nanoscale (ICAN), led by Professor Frank-J. Meyer zu Heringdorf, were able to prove beyond doubt that the areas are exclusively composed of boron atoms and that the nitrogen has disappeared from the sample.
In a next step, the researchers want to investigate how the borophene can be detached from the iridium substrate.
The publication was a result of a collaboration with physicists from the University of Cologne and the Center of Excellence for Advanced Materials and Sensing Devices in Zagreb (Croatia).
Original Publication:
K.M. Omambac, M. Petrović, P. Bampoulis, C. Brand, M.A. Kriegel, P. Dreher, D. Janoschka, U. Hagemann, N. Hartmann, P. Valerius, T. Michely, F.J. Meyer zu Heringdorf, M. Horn-von Hoegen
„Segregation-Enhanced Epitaxy of Borophene on Ir(111) by Thermal Decomposition of Borazine“
ACS Nano, published online March 24, 2021
https://doi.org/10.1021/acsnano.1c00819Further Information:
Prof. Dr. Michael Horn- von Hoegen, Experimental Physics, +49 203/37 9-1438, horn-von-hoegen@uni-due.de
Editor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de
- When will the Solid-state Battery Arrive?
19th April 2021,
Interview with Prof. Hartmut Wiggers.
A crucial strategic component in tomorrow's car is the battery. Solid-state or solid-state batteries promise tremendous progress for their performance. How can the development of solid-state batteries be assessed after the announcements of QuantumScape, Samsung or Toyota?
Prof. Hartmut Wiggers, Materials Chain member, head of the research group "Nanoparticle Synthesis" at the University of Duisburg-Essen and member of the Battery Research Group, talked to Prof. Ferdinand Dudenhöffer about this question in the video.
It should be a small foretaste, because on September 15 and 16, 2021, the Battery Day will take place in Braunschweig for the first time. The event evolves from the Car Symposium in Bochum, but will continue as an independent congress on battery materials and cell production capacities in 2021. Various companies will report there on their activities and products in battery systems and electric drives.
Further information:
To the video: https://www.youtube.com/watch?app=desktop&v=fgFKMq1SsoQ&feature=youtu.be
To the Battery Day: https://www.car-future.com/en/symposium/battery-day/
Kathrin Brüggemeier, kathrin.brueggemeier@car-future.com, +49 (0)203/306-1273 - Electrolysis Technologies
14th April 2021,
From Basic Research to Industrial Application.
Catalysts: Research groups worldwide are working on high-performance materials with challenging compositions, structures and morphologies.
© Fraunhofer UMSICHT/Kevinjeorjios PellumbiThey are essential for so-called "green technologies": electrolysis technologies. There is currently a plethora of catalyst candidates, but almost none of them have been transferred to applications to date. An interdisciplinary team, in which the UDE was also involved, has investigated the reasons for this and what needs to change. They have published their findings in the Journal of American Chemistry Au.
One of their most important findings: The development of electrocatalysts is an endeavor in which industrial and scientific research must work closely together. "There is still a deep, almost insurmountable valley between these two parties," explains Prof. Dr. Ulf-Peter Apfel of Fraunhofer UMSICHT and Ruhr-Universität Bochum.
The team shows what this looks like in practice, using catalysts as an example, among others. On the one hand, research groups worldwide are working on high-performance materials with sophisticated compositions, structures and morphologies. On the other hand, comparatively old or simple catalysts dominate technical and industrial applications. The publication identifies two issues as the cause: both insufficiently developed patenting strategies and insufficient implementation of promising materials under realistic conditions.
UDE Prof. Dr. Doris Segets: "In any project involving catalyst development, it should be clearly defined whether a potential technical application is actually being considered for a particular catalyst candidate or whether fundamental research topics - e.g. mechanistic investigations - are the focus of interest." If an industrial application is being pursued, researchers should look at practical issues such as cost, durability or quantities that can be produced.
In the end, they encourage venturing beyond the immediate field and establishing more intensive collaborations both between different disciplines and with industry.
A full version of the press release can be found here:
Original publication:
D. Siegmund, S. Metz, V. Peinecke, T.E. Warner, C. Cremers, A. Grevé, T. Smolinka, D. Segets, U.P. Apfel.
"Crossing the Valley of Death: From Fundamental to Applied Research in Electrolysis."
JACS Au, published online April 12, 2021
https://doi.org/10.1021/jacsau.1c00092Further information:
Jun.-Prof. Doris Segets, Process Engineering for Electrochemical Functional Materials, Tel. 0203/37 9-8230, doris.segets@uni-due.de - Materials for Energy
13th April 2021,
Materials Chain Workshop .
© Materials ChainBack in February, the Materials Chain flagship program hosted its first digital workshop “Materials for Energy”. We took a look at materials science - at the UA Ruhr and beyond - that focuses on the great challenge to provide our world with more efficient and sustainable energy. As novel materials play a key role for enabling new energy technologies, the fast and efficient discovery and development of novel materials is critical for sustainable future energy.
Over 150 registered participants listened to 18 talks from UA Ruhr materials researchers, and national and international guests from industry and academia and brought the workshop alive by making good use of the online chat and raise hand functions during the vivid discussion times.
In seven sessions, the workshop provided insights from the various key research topics within the UA Ruhr materials research, from magnetic and non-magnetic materials for physical and chemical energy conversion, metals and alloys via data-driven and combinatorial materials discovery to processing and plasma technology.
The workshop closed with an open discussion on future pathways for materials research concerned with sustainable energy. Both the talks and discussion provided impetus for the MCIC 2021 conference, which will take place in November 2021. Planning for MCIC 2021 is currently under way and further information will be made available to you as soon as possible!
- UDE4future: Lecture Series
12th April 2021,
Understanding and Acting on Climate Change.
On 15.04.2021 from 4 pm UDE4future invited you to the first event of the lecture series "Climate Crisis and the Ruhr Area - Understanding and Acting on Climate Change". The lectures, which are easy to understand for laypersons, are largely organized by Dr. Nicolas Wöhrl and Dr. Tobias Teckentrup. They take place twice a month, are aimed at all interested parties - even those without prior knowledge - and are free of charge.
With the lecture series, the action group wants to publicly highlight and jointly discuss various aspects of climate change for the first time at the UDE. In addition to technical and scientific approaches to solving the problem, the focus will also be on key aspects of individual behavioral change.
There will be eight guest lectures, among others by Prof. Schüth from the Max Planck Institute for Coal Research in Mülheim and by Prof. Zellner from the UDE (both CENIDE). Topics include challenges for science, sustainable mobility and urban development, and citizen movements.
The action group UDE4future was founded in January 2020 and sees itself as an open group of active and committed members of the UDE who are committed to a livable, sustainably designed future. The group is made up of students, academic staff, employees from technology and administration, and professors.
Further information, program and registration:
www.uni-due.de/ude4future/ringvorlesung
Dr. Tobias Teckentrup, 0203 379-8178, tobias.teckentrup@uni-due.de
Dr. Nicolas Wöhrl, 0203 379-3131, nicolas.woehrl@uni-due.de - A Stable Copper Catalyst for CO2 Conversion
26th March 2021,
Electrochemistry and Materials Research.
The gas diffusion electrode was analyzed in this measurement chamber. The products were detected with gas chromatography.
© João JunqueiraCO2 can be converted electrochemically into starting materials for industry. So far, however, catalysts that are stable over a long period of time have been lacking. A few tricks could solve the problem.
A new catalyst for the conversion of carbon dioxide (CO2) into chemicals or fuels has been developed by researchers at Ruhr-Universität Bochum and the University of Duisburg-Essen. They optimized already available copper catalysts to improve their selectivity and long-term stability. The results are described by the team led by Dr. Yanfang Song and Professor Wolfgang Schuhmann of the Bochum Center for Electrochemistry with the team led by Professor Corina Andronescu of the Duisburg-Essen Technical Chemistry III group in the journal Angewandte Chemie, published online on 9 February 2021.
Boron makes copper catalyst stableThe climate gas CO2 can be converted into larger carbon compounds that can be used as base chemicals for industry or as fuels. Researchers are pursuing the idea of converting CO2 electrochemically with the help of renewable energies. This would not only create useful products; they would also serve as storage for the renewable energies. Copper has already emerged as a promising catalyst in previous studies, but it must be in the form of a partially positively charged ion – and that is precisely the problem.
Under conventional reaction conditions, copper is rapidly converted from its positively charged form to the neutral state, which is unfavorable for the formation of products with more than two carbon atoms and thus deactivates the catalyst.
The team from Bochum and Duisburg-Essen therefore modified a copper catalyst with boron. The researchers tested different copper-boron ratios and determined the optimal composition to favor the formation of compounds with more than two carbon atoms. They also showed that the boron-copper catalyst can be operated at current densities that would be required on an industrial scale.
Zinc prevents corrosion damageThey implemented the system in the form of a gas diffusion electrode in which a solid catalyst catalyzes the electrochemical reaction between the liquid and gaseous phases. It is important that sufficient CO2 dissolves in the boundary region between the gas and liquid phases. The scientists succeeded in doing this by using a special binder.
Another challenge is to keep the system stable over a long period of time. For example, corrosion of the electrodes must be prevented. To this end, the chemists integrated a so-called sacrificial anode made of zinc into the system. Since zinc is a less noble metal than copper, this is corroded first, while the copper is spared.
“The combination of a selective and active catalyst material in a gas diffusion electrode and the addition of the stabilizing zinc is an important step towards the use of CO2 for the synthesis of base chemicals,” sums up Wolfgang Schuhmann.
Funding
Financial support for the project came from the European Research Council under the European Union’s Horizon 2020 research and innovation program (CasCat, 833408), the German Research Foundation in the framework oft he research unit FOR 2397e2 as well as the Cluster of Excellence Ruhr Explores Solvation – RESOLV (EXC 2033-390677874), the German Federal Ministry of Education and Research (MatGasDif, 03XP0263), the Alexander von Humboldt Foundation, and the International Clean Energy Talent Program.
Original publicationYanfang Song, João R. C. Junqueira, Nivedita Sikdar, Denis Öhl, Stefan Dieckhöfer, Thomas Quast, Sabine Seisel, Justus Masa, Corina Andronescu, Wolfgang Schuhmann: B-Cu-Zn Gas Diffusion Electrodes for CO2 Electroreduction to C2+ Products at High Current Densities, in: Angewandte Chemie International Edition, DOI: 10.1002/anie.202016898
Press contact
Prof. Dr. Wolfgang Schuhmann
Analytical Chemistry
Center for Electrochemistry
Faculty of Chemistry und Biochemistry
Ruhr-Universität Bochum
Germany
Phone: +49 234 32 26200
Email: wolfgang.schuhmann@rub.de - 100,000 Euros for Digital Fellowships
25th March 2021,
Innovations in Digital University Teaching.
Prof. Jeanette Orlowsky from the Faculty of Architecture and Civil Engineering and Dr. Lukas Wojarski from the Faculty of Mechanical Engineering
© Aliona Kardash/TU DortmundPromoting innovative approaches in digital university teaching is the goal of the funding program "Fellowships for Innovations in Digital University Teaching - digiFellows", which the TU Dortmund University announced university-wide with the Ministry of Culture and Science of the State of North Rhine-Westphalia (MKW NRW) and in cooperation with the Digital University NRW (DH.NRW). Now the two winning projects have been announced.
The first funded project is called "Materialcaching - learning app for structured self-study". Prof. Jeanette Orlowsky from the Faculty of Architecture and Civil Engineering and Dr. Lukas Wojarski from the Faculty of Mechanical Engineering are developing an app that sends their students on a search for materials and their manufacturing routes in the Ruhr region. The principle is similar to "geocaching," a popular pastime in which people search for small objects with coordinates or by GPS location, just like a treasure hunt.
Prof. Orlowsky and Dr. Wojarski's students work together in small groups of two to four people. First, they learn about the materials, for example steel, concrete or glass, in the course. By answering technical questions correctly in the app, they receive clues to the coordinates of the site they are looking for. They visit the site, solve further tasks on the spot and document their find with photos. One of the "material caching" locations, for example, is the blast furnace of the Meiderich iron and steel works in the Duisburg-Nord landscape park. During the visit, students learn interesting facts about steel production.
"Material caching allows participants to experience directly how materials are actually used in practice," says Prof. Orlowsky. Dr. Wojarski adds, "With the interactive game-based learning, i.e. the playful transfer of knowledge, we motivate the students in a very special way." The team that is the first to visit nine material caching sites will be rewarded with a small prize.
Portfolio work in digital form
Dr. Nina Göddertz from the Faculty of Education, Psychology and Educational Research is devoting her project "ePortfolios - Personal Learning Environment and Innovative Examination Format" to the digitalization of portfolio work in the social pedagogy teaching degree program. Portfolio work is an integral part of teacher training in social pedagogy at TU Dortmund University and is anchored here in both the Bachelor's and Master's programs. The portfolio to be compiled by the students in the Bachelor's degree consists of subject-related tasks as well as systematic and theory-guided (self-)reflection exercises from two seminars and a lecture.
Dr. Göddertz now wants to digitize this portfolio work as part of the fellowship for the social pedagogy teaching degree program. "I see particular added value here for students, because the ePortfolio allows students to integrate photos, audios or videos in addition to purely text-based content," says Dr. Göddertz. In addition, the ePortfolio enables direct and process-accompanying feedback from the teachers and fellow students and promotes the students' media competence.
Funding of both projects
Both projects are funded by the "digiFellows" program with 50,000 euros each. The program aims to promote the development and testing of digitally supported teaching and examination formats with the consistent use of digital technologies at TU Dortmund University. The projects are funded for one year. Further Digital Fellowships are to be awarded in 2022 and 2023.
- Stable and Catalytically Active Pigment
24th March 2021,
Coating of Single Atomic Layers for Zinc Sulfide.
Artistic representation of the core-shell structures.
UDE/ReichenbergerIt is one of the softest white pigments used by the industry. However, zinc sulfide turns gray over time if it is not appropriately pretreated. Chemists under the leadership of the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) discovered a way to retain its brilliant color and also enable its use as a catalyst; for example, to convert sunlight into usable energy. The scientific journal "Advanced Functional Materials" covers the topic in its latest issue.
Ideally, a pigment should be resistant to corrosion under light irradiation – especially to UV radiation. It should also retain its white color in the long term. Today, the industry has already achieved all this with zinc sulfide, but the resulting material is not suitable to exploit its other feature of triggering photocatalytic reaction because no charge carriers remain on the particle surface.
Cooperating with the Max Planck Institute for Chemical Energy Conversion (Mülheim a.d. Ruhr) and industry partner Venator, UDE chemists from the NanoEnergieTechnikZentrum (NETZ) have now developed an alternative: "We have encased zinc sulfide particles in a protective alumina shell that is just three nanometers thick - atomic layer by atomic layer," explains Dr. Sven Reichenberger, head of the Catalysis Group in Technical Chemistry." These core-shell structures proved stable to high-energy UV irradiation and corrosive media in initial lab experiments.
Possible Use for Sustainable Energy Supply
The additional benefit is that the particles in this form are also conceivable as photocatalysts, i.e. to induce chemical reactions triggered by light, such as the degradation of poisonous chemical compounds in waste water or the splitting of water into oxygen and the energy carrier hydrogen. "For this to happen, electrons would have to be able to penetrate the alumina shell," Reichenberger points out. "This is not yet the case, but we are currently testing whether this can be achieved by an even thinner layer."
If this succeeds, the core-shell structures would be highly interesting for the photocatalytic treatment of wastewater, for example, or for converting solar energy into storable energy carriers.
Original Publication:
T. Lange, S. Reichenberger, M. Rohe, M. Bartsch, L. Kampermann, J. Klein, J. Strunk, G. Bacher, R. Schlögl, S. Barcikowski
„Alumina‐Protected, Durable and Photostable Zinc Sulfide Particles from Scalable Atomic Layer Deposition“
Adv. Funct. Mater. 2021, 2009323
https://doi.org/10.1002/adfm.202009323Further Information:
Dr. Sven Reichenberger, Technical Chemistry I, +49 203/37 9-8116, sven.reichenberger@uni-due.deEditor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de
- 75 Million Euros for New Research Centers
19th March 2021,
UA Ruhr: Change through Science.
Science in the Ruhr region, symbolized here by Tiger and Turtle in Duisburg, is receiving a further boost.
© hagenvontrojaThe state of North Rhine-Westphalia will be funding the Bochum, Dortmund, Duisburg and Essen sites in the coming years.
The University Alliance Ruhr (UA Ruhr) is set to significantly expand its cutting-edge international research efforts. On Wednesday, 17 March, the state government announced its plans to support the alliance in establishing four research centers and a college as part of the Ruhr Conference. This will involve Ruhr-Universität Bochum, TU Dortmund University and the University of Duisburg-Essen consolidating their long-standing cooperation under one new roof – the Research Alliance Ruhr.
Outstanding scientific quality
The state government announced last November that it wanted to set up new, innovative research centers at the UA Ruhr and finance them over the long term in order to promote structural change. The three universities then presented the overall concept of the project in December to a team of experts put together by the German Council of Science and Humanities. The team voted overwhelmingly in favor of the joint project, confirming not only its outstanding scientific quality but also the enormous added value it could bring to the scientific hub of the Ruhr region and beyond. A sum of up to 75 million euros is now being invested in the construction over the next four years, with the buildings set to be fully operational by 2025.
The University Alliance RuhrWith these new research centers, the three universities are pooling their expertise in areas in which they are already conducting internationally renowned, cutting-edge research. The four research centers will deal with future-oriented issues in engineering and the life and natural sciences. The Chemical Sciences and Sustainability center will focus on sustainable solutions based on chemistry, while the center for Trustworthy Data Science and Security will deal with data security. The center for Future Energy Materials and Systems will be dedicated to questions of energy technology, and the One Health center will comprise a holistic approach to research into human health. A college will in turn be established for the humanities and social sciences, which will promote international exchange through research stays.
“With these new structures, the Ruhr region is becoming more appealing for scientists from all over the world who want to address the pressing questions of the future,” said Professor Axel Schölmerich, Rector of Ruhr-Universität Bochum. His colleague in Dortmund Professor Manfred Bayer added: “The entire region will benefit because research generates innovative ideas for practical applications – for large companies as well as for startups.” “The fact that the Ruhr Conference is now sponsoring the UA Ruhr confirms one of our guiding principles – collaboration pays off,” said Professor Ulrich Radtke. The Rector of the University of Duisburg-Essen is one of the founding fathers of the UA Ruhr, which began in March 2007 with the signing of a cooperation agreement between the three partner universities.
Minister-President of North Rhine-Westphalia Armin Laschet called the project “a new coalition of innovation”. Minister of Culture and Science Isabel Pfeiffer-Poensgen said that the state government wants to “take the Ruhr Area’s international reputation as an excellent scientific region to a whole new level” with this decision. Dr. Stephan Holthoff-Pförtner, Minister for Federal, European and International Affairs and leader of the Ruhr Conference, emphasized that the Ruhr Conference was established to harness the potential of the metropolitan region on a broad front: “The new research centers show we are making good progress.”
Before the actual implementation can begin, the recommendations of the expert team appointed by the Council of Science and Humanities must first be evaluated in detail.
- Alloys that Find Themselves
12th March 2021,
New Project.
Alfred Ludwig looks into a window of the sputtering plant.
© Christian NielingerA team at the Center for Interfacially Dominated High-Performance Materials is searching atomic mixtures of many different elements for new high-entropy alloys that hold promise for many applications.
Materials composed of five or more elements in approximately equal amounts could help overcome previous limitations in, for example, catalysis. Theoretically, there are millions of possible combinations - one challenge is to find the right ones. A research team led by Prof. Dr. Alfred Ludwig, holder of the Chair of New Materials and Interfaces at the RUB, is taking an unconventional approach: It is bringing together 20 to 30 starting elements in a perfect initial mixture, then exciting this mixture energetically and determining with atomic precision which complex alloys will result. The project is funded by the Volkswagen Foundation in the program "Experiment! In Search of Daring Research Ideas" program for 18 months with funding of around 120,000 euros.
Properties are promising
The so-called high entropy alloys, or HEA for short, promise, among other things, the development of novel electrocatalysts based on non-toxic and abundantly available elements that have the same performance as those that are rare and expensive because they are based on platinum or iridium, for example. "It has been shown that the number of five different elements is crucial for such materials," says Alfred Ludwig. How to quickly find the right ones in the multitude of possible combinations is the subject of research.
For the current study, the research team is relying on a special technique: in a sputtering system, starting elements are deposited in atomic form on a carrier material consisting of many tiny silicon tips. A small volume forms on the tips, which are in almost no direct contact with the carrier material. "These accumulations of a few million atoms on each tip are our nanoreactor," Alfred Ludwig explains. Using atomic probe tomography, the researchers can examine the resulting material on these coated tips and find out, for example, whether it is stable and at what temperature the individual elements separate again. Atomic probe tomography makes it possible to visualize many millions of atoms and their three-dimensional arrangement and to distinguish between different elements.
The idea of the new project is to sputter 20 to 30 non-toxic and available elements simultaneously onto such silicon substrates and then investigate which polyelementary combinations can form from them. In this way, a large number of new HEAs should be efficiently discovered.
- Switching Off the
8th March 2021,
Success of Interdisciplinary Collaboration.
Graphical representation of the protein "Survivin" (red, pink) and the tailored ligand (gray, yellow) in water (blue).
© Sanchez-GarciaIt is called the "survival protein" because it plays a central role in the growth of cancer cells: survivin influences two important processes in the body's cells at the same time – cell death and cell division. Chemists and biologists from the CRC 1093 and CENIDE have now succeeded in developing a precise molecule that can bind the protein’s surface at a defined site and switch it off. "Nature Communications" covers the topic.
Proteins control almost all vital processes in our cells. If they do not function correctly, if there is too much or too little of them, this can lead to the development of a variety of diseases including cancer. The associated proteins are therefore also important targets for drug discovery in biomedical research.
However, there are large number of proteins that simply do not offer suitable targets for a conventional active ingredient to dock onto. That's why scientists in UDE’s Collaborative Research Center 1093 are developing small, unusual molecules called supramolecular ligands that can precisely bind to their surface.
Molecules block pivotal site of the protein
Recently, the team of scientists led by Prof. Shirley Knauer, Prof. Elsa-Sanchez-Garcia and Prof. Thomas Schrader succeeded in targeting a critical interface that is important for the survival of cancer cells with such customized molecules. "The protein survivin is actually hardly found in healthy adult organisms," so Prof. Shirley Knauer. "In cancer cells, however, its production is ramped up." Using an artificial, tailored ligand, the scientists were able to cover the exact site of the survivin, which is responsible for its activation and transport out of the cell nucleus.
Each protein has a unique three-dimensional structure with a fissured surface that can form loops and niches. Sanchez-Garcia and her team performed computational analyses of the protein's surface and found out that the important interface is on an ordered but somewhat dynamic loop. Using this information and following further structural analyses, the chemists led by Schrader were able to design the ligand for this particularly difficult surface.
Original Publication:
A. Meiners, S. Bäcker, I. Hadrovic, C. Heid, C. Beuck, Y. B. Ruiz-Blanco, J. Mieres-Perez, M. Pörschke, J.-N. Grad, C. Vallet, D. Hoffmann, P. Bayer, E. Sanchez-Garcia, T. Schrader, S. K. Knauer
“Targeting a protein epitope: Specific inhibition of the Survivin-CRM1 interaction by peptide-modified molecular tweezers.”
Nature Communications 2021
https://doi.org/10.1038/s41467-021-21753-9Further Information:
https://www.uni-due.de/crc1093/
Prof. Dr. Shirley Knauer, Molecular Biology II, +49 201/18 3-4987, shirley.knauer@uni-due.deEditor: Dr. Lydia Didt, CRC 1093, +49 201/18 3-4351, lydia.didt@uni-due.de
- Robot Helps to Fight Hospital Germs
23rd February 2021,
Medicine/Electrical Engineering.
Hero in use in orthopedics
© ICA Health/ Ida Andrea"Hero21" disinfects with UV light.
A self-propelled robot disinfects surfaces with UV-C radiation at RUB's St. Josef Hospital. This is not only fast, but also thorough: the inactivation rate of germs on surfaces increases from 77 percent after normal disinfection to 96 percent after its use. The device was developed by the medium-sized Dortmund-based technology specialist ICA Traffic GmbH, supported by the Chair of General Electrical Engineering and Plasma Technology at the RUB.According to the Robert Koch Institute, between 400,000 and 500,000 patients become infected with hospital germs in German hospitals every year. Therefore, thorough and reliable disinfection of medical equipment and surfaces in hospitals is of particular importance. Long before Corona, the Catholic Hospital in Bochum (KKB) had already addressed this issue and is now taking the next step. With the "Hero21" - short for Health Robot - a self-propelled UV-C disinfection robot is being used for the first time.
Impressive results in the laboratory
The robot was extensively tested in the laboratory and already achieved impressive results there. Even resistant pathogens such as methicillin-resistant Staphyloccocus Aureus (MRSA) or vancomycin-resistant enterococci were reliably killed. The robot has been in use as a pilot at St. Josef Hospital since October. It supports the cleaning staff by carrying out disinfection using UV-C radiation in addition to disinfecting cleaning. This combined disinfection has reduced the number of germs to a minimum. Compared to disinfecting cleaning, the so-called inactivation rate of all germs detected by so-called swab samples on all conceivable surfaces increased from 77 to 96 percent. The robot needs just ten minutes to disinfect a patient room or functional area.
"The best result with a significant increase in the disinfection result is achieved when scrub-wipe disinfection and the robot are used in combination," explains Dr. Friederike Lemm, head of hospital hygiene at KKB. "Especially for high-infection areas or in places with a high disinfection effort, the robot is a good addition." ICA Managing Director Stefan Walko emphasizes, "I am pleased that the Hero21 could be embedded so well and efficiently into the daily hospital routine. This very good interdisciplinary cooperation between industry, science and clinical practice is a prime example of innovative solutions from the Ruhr region."
Eliminates the most difficult germs
The RUB had deliberately set the bar high in the laboratory. The robot was applied to spores of Bacillus subtilis, a typical test bacterium, where it achieved a reduction of 99.9 percent. Prof. Dr. Peter Awakowicz, Chair of General Electrical Engineering and Plasma Technology: "These endospores are among the most resistant microbes and the most difficult to inactivate. Anyone who cracks them is able to significantly reduce or even completely inactivate all vegetative bacteria and also viruses." In this respect, the reduction achievements of Hero21 are also strong evidence for the fight against Covid-19.
Prof. Dr. Stephanie Pfänder from the Department of Molecular and Virological Medicine at RUB and a specialist in the field of coronavirus research, confirms, "We tested UV-C irradiation against an annually circulating endemic coronavirus and found a strong reduction of viral load on surfaces. We expect these results to be applicable to Sars-Cov-2 as well." Scientific results on the effect of the disinfection robot will be published soon.
St. Joseph Hospital will now continue to use the robot. ICA, in turn, sees the successful test operation in Bochum as the starting point for a nationwide and international marketing offensive.
- Interdisciplinary Discussion of Aerosol Technologies
19th February 2021,
Meeting of SPP1980, FOR2284 and ProcessNet Specialist Group.
© CENIDEAerosol processes are essential in materials synthesis, the chemical industry and food technology. On May 17 and 18, experts from industry and science will discuss current research approaches and the state of the art in a Webex event. Participation is free of charge, and registrations are possible until May 3.
Particularly in spray flame and gas phase synthesis of nanoparticles, a deeper understanding of the complex particle formation mechanisms is required to optimize the process design and produce functional materials with a wide range of properties. It is a prerequisite for the development and application of specific in situ analytical methods, the generation of chemical mechanisms by basic kinetic experiments and theoretical calculations, and for comprehensive simulation of the entire process chain.
The main focus of the event:
Nucleation and condensation processes in the gas phase
Aerosol reactors and equipment for the technical production of functional particles
Adjustment of structural and functional particle properties
Generation of particle structures on substrates
Aerosol measurement technology
Submissions of papers will be accepted until February 28.The meeting is organized by the ProcessNet Aerosol Technology Division, the DFG Priority Program SPP1980 "Nanoparticle Synthesis in Spray Flames" and the research group FOR2284 "Model-based Scalable Gas Phase Synthesis of Complex Nanoparticles."
More information and registration:
https://www.uni-due.de/cenide/jahrestreffen_aero_2020
Steffi Nickol, Tel. 0203/37 9-8177, steffi.nickol@uni-due.de - Breakthrough for Magnetic Resonance Imaging
17th February 2021,
New Antenna is an All-round Talent.
The leaky wave antenna is built of periodic metamaterial structures.
© ATEAnyone needing a tomography gets the clearest possible images of an organ or other body structure slice by slice. But the further inside the potential problem lies, the more difficult it is to obtain high-resolution images in magnetic resonance imaging. An international team of scientists led by the University of Duisburg-Essen (UDE) has developed a high-frequency coil that allows for much better range inside the body – among other advantages. The scientific journal "Nature Communications" covers the topic.
Magnetic resonance imaging (MRI) at 7 tesla is the latest generation of this technology and offers images with a significantly higher-resolution than the classic devices, working with a maximum magnetic flux density of 3 tesla. However, the high-frequency magnetic fields at 7 tesla in particular are strongly absorbed by body tissue and therefore only poorly reach organs that are located far inside, such as the heart or prostate.
Long range, thereby broadband and efficient
Dr. Jan Taro Svejda from the Department of General and Theoretical Electrical Engineering (ATE) and the Center for Nanointegration (CENIDE) – together with colleagues from the ITMO University of St. Petersburg (Russia), the Technical University of Eindhoven and the University Hospital of Utrecht (both in the Netherlands) – has developed a new high-frequency coil with three decisive properties: The composite made of periodic metamaterial structures directs the energy into the radiated magnetic field as effectively as possible. This avoids an intense magnetic field directly around the antenna – and thus also on the body under examination. At the same time, this leads to a greater range because less energy is absorbed by the tissue.
The third advantage comes with the possibilities offered by this new type of leaky wave antenna: Conventional MRI antennas excite the resonance of hydrogen atomic nuclei in the body. Cartilage, however, could be better represented using the resonance of sodium nuclei, for example; but to date, this would require a different antenna with the appropriate operating frequency. "Our coil, on the other hand, can also generate such alternative magnetic resonances," Svejda explains. "In other words, complementary MRI images, which additionally highlight tissue structures containing sodium, such as cartilage, can be produced with only one antenna."
As a next step, the team is now working on a new version of the metamaterial structure that can further enhance the image quality from inside the body.
Original Publication:
G. Solomakha, J. T. Svejda, C. van Leeuwen, A. Rennings, A. J. Raaijmakers, S. Glybovski, D. Erni
"A self-matched leaky-wave antenna for ultrahigh-field MRI with low specific absorption rate,"
Nat. Commun., vol. 9, article no. 455, pp. 1-11, Jan. 19, 2021
DOI: 10.1038/s41467-020-20708-wFurther Information:
Prof. Dr. sc. techn. Daniel Erni, General and Theoretical Electrical Engineering (ATE), +49 203/37 9- 4212, daniel.erni@uni-due.deEditor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de
- Quickly Identifying High-Performance Multi-Element Catalysts
17th February 2021,
Electrochemistry and Materials Research.
Hundreds of possible material combinations can be tested on such a carrier.© Tobias LöfflerFinding the best material composition among thousands of possibilities is like looking for a needle in a haystack. An international team is combining computer simulations and high-throughput experiments to do just that.
Catalysts consisting of at least five chemical elements could be the key to overcoming previous limitations in the production of green hydrogen, fuel cells, batteries or CO2 reduction. However, finding the optimal composition of these multi-element catalysts is like looking for a needle in a haystack: Testing thousands to millions of possible combinations cannot be realized. Research teams from Ruhr-Universität Bochum (RUB) and the University of Copenhagen have therefore developed an approach that can predict the optimal composition and confirm its accuracy with high-throughput experiments. They report in the journal Angewandte Chemie International Edition, December 28, 2020.
Much less expensive elements than previous catalysts
Many electrochemical reactions go through multiple steps. Each should be optimized on a catalyst surface if possible, but different requirements apply to each step. "Since previous catalysts usually only have optimized functionality, only the best compromise was possible, and energy losses could not be avoided," explains Prof. Dr. Wolfgang Schuhmann of the Center for Electrochemistry at RUB. With complex solid solutions, several functionalities can be realized simultaneously on one catalyst surface, overcoming this limitation. However, this only happens when at least five different elements are combined. Millions of possibilities exist as to the percentage ratios in which the respective elements can be combined. The previous challenge of searching for a strategy to find optimal properties seems to be answerable with this class of materials. Now the challenge is to figure out which combination best meets the goal. "Incidentally, this may also be possible with much cheaper elements than with previous catalysts," Schuhmann emphasizes.
Making and testing predictions
In their work, the research teams present an approach that offers guidance among the myriad possibilities. "We have developed a model that can predict the activity for oxygen reduction as a function of composition, allowing calculation of the best composition," explains Prof. Dr. Jan Rossmeisl of the Center for High Entropy Alloy Catalysis at the University of Copenhagen.
The team from Bochum provided the verification of the model. "We can use a combinatorial sputtering system to produce material libraries where each point on the surface of the support has a different composition and there are different but well-defined gradients in each direction," explains Prof. Dr. Alfred Ludwig from the Chair of New Materials and Interfaces at RUB. Using a scanning droplet cell, the catalytic properties of 342 compositions on a material library are then automatically measured to identify activity trends.
"We found that the original model did not yet do justice to the complexity and still made imprecise predictions. Therefore, we revised it and had it tested again experimentally," says Dr. Thomas Batchelor from the Copenhagen team, who was a visiting scientist at RUB as part of the collaboration. This time, prediction and experimental measurement showed excellent agreement, which was confirmed by further material libraries.
This strategy allows the complex mechanisms at the surfaces, which consist of five chemical elements, to be identified, leaving most of the screening effort to the computer. "If the model turns out to be universally applicable to all element combinations and also to other reactions, one of the currently biggest challenges of this catalyst class would be realistically met," the team said.
Funding
The work was funded by the German Research Foundation under the Excellence Strategy (EXC 2033-390677874 Resolv) and in projects LU1175/22-1 and LU1175/26-1, and by the European Research Council (Cascat 833408). There was also support from the Danish National Research Foundation Center for High-Entropy Alloy Catalysis (Cheac) DNRF-149 and Villum Fonden Science Grant 9455. In addition, there was funding from the IMPRS Surmat grant and support in materials characterization from the Center for Interfacially Dominated High-Performance Materials (ZGH) in Bochum, Germany.Original publication
Thomas A. A. Batchelor et al: Complex solid solution electrocatalyst discovery by computational prediction and high-throughput experimentation, in Angewandte Chemie International Edition, 2020, DOI: 10.1002/anie.202014374.Press contact
Prof. Dr. Alfred Ludwig
New Materials and Interfaces
Institute for Materials
Faculty of Mechanical Engineering
Ruhr University Bochum
Phone: +49 234 32 27492
E Mail: alfred.ludwig@rub.deProf. Dr. Wolfgang Schuhmann
Analytical Chemistry - Center for Electrochemistry (CES)
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 26200
E Mail: wolfgang.schuhmann@rub.deProf. Dr. Jan Rossmeisl
Center for High Entropy Alloy Catalysis (CHEAC)
Faculty of Chemistry
University of Copenhagen
Denmark
Tel: +45 50 71 95 84
E Mail: jan.rossmeisl@chem.ku.dk - Poster Award for Research on High-Performance Batteries
11th February 2021,
Battery Forum Germany 2021.
© Stefan KilianStefan Kilian from the Wiggers research group at the University of Duisburg-Essen (UDE) was awarded a poster prize at the Battery Forum Germany 2021. The topic was his research on silicon nitride nanoparticles for high-performance lithium-ion batteries. He took 3rd place, which comes with prize money of 500 euros.
Electromobility is to become suitable for mass use - this requires high-performance batteries to improve the driving performance of electric vehicles and shorten charging times. Silicon is a promising component for this. However, to enable the batteries to discharge and charge without a major change in volume, research is currently being conducted into various nanostructures and composites. Kilian is working on SiNx nanoparticles, which contain nitrogen as well as silicon. Nitrogen stabilizes the silicon in batteries and is expected to improve cycle performance - the results so far are promising.
The Battery Forum Germany took place for the ninth time in 2021 and is organized by the Competence Network Lithium-Ion Batteries (KLiB) with support from the German Federal Ministry of Education and Research (BMBF). The invited speakers from industry, science and politics illuminate the topic of batteries from different perspectives and engage in discourse.
- Short Talk Award for Tigges
8th February 2021,
South East Asia Symposium.
© Nicolas WöhrlSharing science, networking science - on November 24 and 25, 2020, the sixth South East Asia Symposium on Energy Materials was held online. Co-organizers included the University of Tsukuba (Japan), a partner university of the University of Duisburg-Essen (UDE). Sebastian Tigges, a PhD student in AG Lorke, received a Short Talk Award for his talk on the synthesis of electrocatalysts.
It is precisely this process of synthesis that he, together with Dr. Nicolas Wöhrl and Professors Axel Lorke and Stephan Schulz, has significantly developed over the past four years - shortening the normally three-, four-, eight-step catalyst production process to a single step. In 2019, the logical step was to apply for a patent. The electrocatalysts are synthesized in a plasma system and used, for example, in fuel cells or in electrolysis cells.
The goal of the South East Asia Symposium is to promote scientific communication, collaboration and student exchange between universities in Southeast Asia and research institutes in Tsukuba. The focus is on energy and environmental topics such as photovoltaic materials, fuel cell catalysts, batteries and photomaterials.
- GUIDEPLUS Receives 3.5 Million Euros
3rd February 2021,
Milestone for New Start-up Era.
Supporting ideas, promoting startups: In recent years, the UDE has increasingly created structures and its own center for startup activities. Now, two co-creation labs are to be created - these are fully equipped workspaces where teams of founders can try their hand. They are part of the GUIDEPLUS project , for which the university will receive 3.5 million euros from the NRW Ministry of Economics until 2024.
Since mid-2019, the "Center for Start-ups and Innopreneurship", or GUIDE for short, has existed at the research-strong UDE. It advises people interested in founding a company and also supports them in the implementation of their ideas. The GUIDEPLUS project, which is now being funded, is not only linked to this in name: "It is an important building block for making our many outstanding research results visible beyond the region. As a university, we are actively helping to shape the transformation of the Ruhr region into a research and start-up metropolis," says Prof. Dagmar Führer-Sakel, Research Vice Chancellor, who is delighted about the funding decision from Düsseldorf.
Minister of Economics and Digital Prof. Andreas Pinkwart affirms: "The GUIDEPLUS project of the University of Duisburg-Essen uses the great potential of the university and underlines the clear will of the university management and professors to dedicate themselves even more intensively to the topic of start-ups in research, teaching and transfer," says the minister. "Together with the two Excellence Start-up Centers at the Ruhr-Universität Bochum and the Technische Universität Dortmund, we are thus sustainably strengthening the start-up ecosystem in the Ruhr region. This is an important milestone for the New Start-up Era in North Rhine-Westphalia."
Co-Creation Labs
To strengthen the importance of startups in the faculties, the university is establishing two new startup-oriented professorships.In addition, two co-creation labs are being created - one with a digital focus in Duisburg and one with a focus on product innovation in Essen led by Prof. Michael Giese. "The workspaces will be fully equipped - from cloud infrastructures to 3D printers. After all, the point is to enable founding teams to implement their ideas and approaches quickly and easily, be it for the development of sustainability apps or innovative materials. This enables them to better prepare for the next steps - founding and market entry," explains project manager Prof. Frederik Ahlemann.
Further information:
Prof. Dr. Frederik Ahlemann, Business Informatics and GUIDEPLUS Project Manager, Tel. 0201/18 3-4250, frederik.ahlemann@uni-due.de
Bernhard Schröder, GUIDE, Tel. 0201/18 3-6863, bernhard.schroeder.ssc@uni-due.de - A Brilliant Source of Single Photons
29th January 2021,
Physics.
A single-photon source opens up new possibilities in quantum communications
© Universität Basel, Departement PhysikThe results are another step towards quantum communication.
Researchers from the University of Basel and the RUB report on a new single-photon source with record efficiency. Billions of single photons can be generated per second and measured at the output of a standard optical fiber line. The source represents a new and powerful building block in the burgeoning field of quantum technology. The work was done in collaboration between physicists at the University of Basel, Switzerland, and RUB. The team published their findings in the journal Nature Nanotechnology, published online Jan. 28, 2021.Light is not only wave, but also particle: indivisible packets of light, also called quanta or photons. This duality between wave and particle, proven for more than 100 years, is described in quantum mechanics. Researchers around the world are trying to inscribe information in a wide variety of quanta and then use them to perform quantum information processing. In the future, this may enable tap-proof communication or even quantum computations.
Communication via photons
One conceivable realization of such quantum switching units are single photons. A single photon can transport the information encoded in its quantum state over long distances. This property makes single photons indispensable in quantum cryptography, where a message is encoded in a chain of single photons. The "no cloning" theorem of quantum physics prohibits the creation of an exact copy of the photon chain, so secure communication can be guaranteed.
In the future, remote quantum processors will communicate with each other via single photons. And perhaps the processor itself will use photons as quantum bits. A prerequisite for the realization of these concepts is a single photon source, a novel light source that generates one and only one photon at each excitation.
Quantum dots from Bochum
Natasha Tomm and Alisa Javadi of the University of Basel describe such a single-photon source in Nature Nanotechnology with an efficiency never before achieved. Each photon is produced by exciting a single artificial atom, called a quantum dot, made in Bochum, Germany, within a semiconductor designed by Dr. Arne Ludwig and fabricated by his team at RUB.
The portion of the light visible to humans spans a wavelength range from about 380 nanometers (violet) to 800 nanometers (red). Photons with longer wavelengths in the infrared spectral range are of interest for light-based communication over long distances. Fiber optic lines have very low absorption in that range and signals need to be amplified less often. Each individual photon from the semiconductor quantum dots consists of a wave train with a wavelength of about one micrometer, i.e. in the infrared spectral range just out of sight of the human eye. The wave trains themselves (i.e. the photons) each have a length of about two centimeters.
Funnel captures photons
Normally, these photons go in all possible directions and only a small fraction is ever detected. Here, however, the quantum dot is positioned in a funnel to send all the photons in a specific direction. The funnel, a new type of micro-cavity resonator, is at the heart of this success: it captures almost all the photons and then directs them into an optical fiber. At 57 percent, the efficiency of the entire system is more than double that of previous single-photon sources.
"This is a really special moment," explains Richard Warburton, group leader of the Basel team. "We've known for a year or two what was possible in principle. Now we've managed to put our ideas into practice. The increase in efficiency has massive consequences: for example, there is a computational advantage of about one million when working with a chain of 20 photons. In the future, we want to make our single photon source even better, we want to simplify it and pursue some of its myriad applications."
Funding
The project was supported by the Swiss National Science Foundation, the National Center of Competence in Research "Quantum Science and Technology" (NCCR QSIT), the European Union under the Horizon2020 program, DFH/UFA CDFA05-06, the German Research Foundation (TRR160, 383065199), and the German Federal Ministry of Education and Research (project Q.Link.X).
Original Publication
Natasha Tomm, Alisa Javadi, Nadia O. Antoniadis, Daniel Najer, Matthias C. Löbl, Alexander R. Korsch, Rüdiger Schott, Sascha R. Valentin, Andreas D. Wieck, Arne Ludwig, Richard J. Warburton: Eine helle und schnelle Quelle für kohärente Einzelphotonen, in: Nature Nanotechnology, 2021, DOI: 10.1038/s41565-020-00831-x
- Plasma Structures Analysed in Detail
15th January 2021,
High-Performance Plasmas.
The gas inside the plasma chamber is ionized and starts to glow.
© Damian GorczanyOnce the inhomogeneous character of plasmas became apparent, not everyone was pleased. However, this characteristic has some advantages, for example for the industry.
They are often invisible to the naked eye: the wafer-thin layers that are deposited on surfaces with the help of plasmas. For example, on architectural glass to control its reflectivity, on tools to protect them from wear and tear, or on plastics to make them more impermeable to gases. Plasma coatings have become indispensable in industrial applications. While surfaces can also be coated using chemical processes, this would sometimes require such high temperatures that the coated objects would melt. Plasmas, on the other hand, generate the required energy not through heat, but through the reactive particles they contain.
In a plasma, matter is partially or completely ionised. By applying electric fields to electrodes in a plasma chamber, the introduced gas, such as argon, can be ionised and the charged particles are accelerated towards a metal electrode. The ions impinging on the metal knock individual atoms out of the material, which are then deposited on a workpiece that is located across from it and is to be coated. The team of the Collaborative Research Centre SFB/TR 87 explores what exactly happens in the plasmas during such coating operations. The researchers have been studying the underlying processes for years.
Hype and valley of tears
“At our Collaborative Research Centre, we experienced both the hype surrounding high power pulsed plasmas for superior coatings a good ten years ago and the subsequent deep valley of tears,” recalls Professor Achim von Keudell, who holds the professorship for Experimental Physics of Reactive Plasmas at RUB. In 1999, the so-called High-power Impulse Magnetron Sputtering was established. The process uses fully ionised plasmas whose surfaces have a power density that pretty much equals that of rocket engines. In contrast to conventional plasmas, these high-power plasmas can’t be operated continuously, because they would destroy the materials of the plasma chamber. Therefore, they are repeatedly switched on and off, i.e. run in pulsed mode.
These dense plasmas can also be used to produce correspondingly dense high-quality coatings. Consequently, this technology immediately sparked interest in the industry. “Then, disillusionment hit,” says von Keudell. This is because the higher quality of the layers came at the expense of the coating rate, which in some cases was only 30 percent of those achieved by traditional processes at the same electrical power input.While conventional processes mainly use uncharged atoms, radicals or molecules for coating, high-performance plasmas primarily produce ions. Since the particles are charged, they are heavily affected by external and internal electric fields. Due to the direction of these electric fields, a large proportion of the ions that travel towards the workpiece simply turn back halfway and fly back. This phenomenon is called the return effect and can’t be circumvented because it is simply due to the property of fully ionised plasmas. “For ten years, the plasma community has been struggling and failing to achieve both a high-quality layer and a high growth rate. It doesn’t work, you have to decide which is more important depending on the application,” elaborates von Keudell.
However, a larger number of the ionised particles make it to the other side through the electric fields and settle there as a layer than one would expect according to simple plasma models. This is thanks to another phenomenon that the Bochum team has now researched in depth: although the high-power plasmas look very uniform when viewed with the naked eye, they actually contain structures that help the ions to get to the other side.
Croissants and comets
Viewed from above, the plasmas are toroidal, they resemble a glowing donut. This glow of the excited particles forms structures that move in circles at ten kilometres per second and can only be detected by high-speed cameras. “One of the first structures we observed in an aluminium plasma at that time looked like a comet flying backwards,” describes Achim von Keudell. In subsequent analyses, the Bochum-based researchers found that different structures were formed, depending on the type of plasma. In a titanium plasma, for example, not a single comet is formed, but rather something that looks like a croissant. The number of structures in the torus also changes depending on the plasma conditions. Because of the regularity and rotation of the structures, the term “rotating plasma spokes” has been adopted.
The description of these inhomogeneities in technical plasmas caused a stir in the research community, especially among scientists working in applied fields. Today, Achim von Keudell is convinced: “It was probably unfortunate that we basic researchers spoke of inhomogeneities or instabilities. A process engineer doesn’t like the sound of that.”Stabile instabilities
It turned out that although these structures are created by instability at the beginning of each plasma pulse, the final structure is very stable. Structure formation is an essential property of high-power density plasmas and can’t be entirely prevented, but it doesn’t pose a problem for coating processes, either. On the contrary, it even helps to mitigate the return effect. Without the inhomogeneities, there would be no efficient layer growth at all in fully ionised plasmas, because many ions deflected by the electric fields would never reach the surface.
Because the luminous plasma spokes are electrically charged, they don’t interlock; once the structure is formed, it is stable. And because it moves at high speed, it does not affect the coating finish. Only under certain conditions can the structures freeze in their motion, which would indeed lead to an uneven coating. “In the meantime, however, we have understood the plasmas to such an extent that we know how to choose the parameters to prevent such an outcome,” says Julian Held, PhD researcher at the Chair of Experimental Physics II. “We can even specifically grow certain structures in the lab.”
Julian Held has perfected the method. He developed a technique that allows him to analyse structures in a plasma synchronised with high-speed cameras. Thus, he can also render the different plasma components visible separately from each other, such as the glow of certain atoms or ions, and correlate their movements in time and space. “For years, we had tons of individual images but never knew how to superimpose them,” Held recalls. “This project was an essential step in creating detailed plasma models.”
- Future Options for Storing CO2
14th January 2021,
Synthesis of Inorganic Heteroalkenes.
Structures of the gallaphosphene (1) and the complex of CO2 (2) and acetophenone (3).
© UDEGroup 13/15 heteroalkenes RMER' with M-E double bonds (M = B-Tl; E = N-Bi) offer promising potential for bond activation reactions, but they are difficult to prepare. A team led by CENIDE professor Stephan Schulz now describes new synthetic methods for group 13 metallapnictenes in no less than three articles in the journal "Angewandte Chemie". They allow for the preparation of preparative amounts as a basis for systematic reactivity studies.
It was shown that the gallaphosphene L(CL)Ga=P-GaL (L = β-diketiminate) not only selectively activates the C(sp3)-H bonds of acetone and acetophenone, but also CO2. The latter reaction is even completely reversible in this process, and thus the bound CO2 can be re-released with reversion of the gallaphosphene at 90 °C.
"I would never have thought that such a reversible reaction, that reveals new options in CO2 storage, was possible. Together with CH activation, the supreme discipline in organometallic chemistry, this results in a wide range of options – including catalytic reactions," Schulz says.
Original Publications:
B. Li, C. Wölper, G. Haberhauer, S. Schulz
Synthesis and reactivity of heteroleptic Ga-P-C allyl cation analogues
Angewandte Chemie International Edition, 2021
DOI: 10.1002/anie.202012595
https://onlinelibrary.wiley.com/doi/10.1002/anie.202012595Krüger, C. Wölper, S. Schulz
From π-bonded gallapnictenes to nucleophilic, redox-active metal-coordinated pnictanides
Angewandte Chemie International Edition, 2021
DOI: 10.1002/anie.202013618
https://onlinelibrary.wiley.com/doi/full/10.1002/anie.202013618K. Sharma, C. Wölper, G. Haberhauer, S. Schulz
Multi-talented gallaphosphene for Ga–P–Ga heteroallyl cation generation, CO2storage and C(sp3)–H bond activation
Angewandte Chemie International Edition, 2021
DOI: 10.1002/ange.202014381
https://onlinelibrary.wiley.com/doi/10.1002/anie.202014381Further Information:
Prof. Dr. Stephan Schulz, Anorganic Chemistry, +49 201/18 3-4635, stephan.schulz@uni-due.de
- Outstanding Research Work on Hydrogen in North Rhine-Westphalia Honored
13th January 2021,
Special Jury Prize.
Professor Dr. Andreas Pinkwart with award winners
© MWIDE NRWWhere can plants for converting electricity from renewable energies into green gases be built? Which fuels made from hydrogen or CO2 are suitable for sustainable, CO2-neutral transportation systems? As part of the EnergyResearchOffensive.NRW, Innovation and Energy Minister Professor Dr. Andreas Pinkwart awarded the Energy Research Prize 2020 to four outstanding research projects on the subject of hydrogen on January 13.
Prizes were awarded for final theses by young scientists at universities in North Rhine-Westphalia in the categories Bachelor's, Master's and dissertation. A special jury prize was also awarded.
Minister Pinkwart: "Climate change and the transformation of the energy system present us with major challenges. Innovations are the key to the transformation to the climate-neutral industry of the future. Exciting ideas, innovative technologies and advanced practices are central to a climate-neutral industry and the success of the energy transition. The state government wants to strengthen research and development in this area and thus significantly advance North Rhine-Westphalia on its way to becoming a hydrogen state. The Energy Research Award is intended as motivation to continue actively shaping the transformation of the energy system with clever ideas and approaches. I am very pleased that so many outstanding research papers have been submitted for the Hydrogen Energy Research Award and it shows that we are absolutely on the right track."
An independent jury of five renowned scientists judged the submitted papers based on the following criteria: Quality of the scientific thesis, consistency with the strategies and goals of North Rhine-Westphalian energy research, relevance for North Rhine-Westphalia as a research and business location, and transferability of the research results into practice.
Special jury prize
The jury's special prize for an outstanding dissertation with a particularly innovative approach, practical relevance and practicality went to Dr. Tobias Löffler from the Ruhr Universität Bochum. In his dissertation, Dr. Tobias Löffler researched ways to develop novel electrocatalysts for energy conversion. "With this work, Dr. Tobias Löffler has developed important basic principles and made a substantial contribution to solving the problem of necessary energy storage in connection with the volatile supply of electricity from renewable sources such as wind and sun and efficient energy conversion by electrochemical conversion in fuel and electrolysis cells in the energy transition," the jury stated. The scientific results and findings of this work are already being incorporated into a concrete application reference within the framework of the Future Cluster Initiative of the German Federal Ministry of Education and Research. The jury's special award is a non-material prize: the winner is given the opportunity to present his or her work at a specialist forum.
Current call for entries: Battery development
This year, the Ministry of Economic Affairs and Energy is awarding prizes for outstanding theses on the topic of battery development. Bachelor's, master's and doctoral theses whose completion date is no older than February 28, 2019 are eligible. Applications for the Energy Research Award can still be submitted online via the website of Project Management Jülich until February 28, 2021: www.ptj.de/energieforschungspreis - Battery Research Group founded
22nd December 2020,
Further Development of Lithium-ion Technology.
© CAR-Center Automotive ResearchBringing findings from basic research even faster into application is the declared goal of the newly founded "Battery Research Group", of which Prof. Christoph Schulz from University of Duisburg-Essen (UDE) is also a member. In a video interview*, he and his three colleagues explain their respective focal points.
They want to contribute to the further development of lithium-ion technology through the exchange of top scientists with industry: Prof. Christof Schulz (CENIDE), Prof. Arno Kwade (Institute for Particle Technology at the Technical University of Braunschweig), Prof. Maximilian Fichtner (Helmholtz Institute Ulm and Karlsruhe Institute of Technology) and Prof. Ferdinand Dudenhöffer (CAR-Center Automotive Research).
Continuous symposia will be held to ensure exchange with industry. Battery Day 2021 is planned for March 10 and 11 in Braunschweig and Salzgitter.
* To the video conversation:
https://www.car-future.com/de/battery-research-group/#battery-group-event
Further information:
Prof. Dr. Christof Schulz, Institute of Combustion and Gas Dynamics - Reactive Fluids, Tel. 0203/37 9-8163, christof.schulz@uni-due.de - New Energy Conversion Layer for Biosolar Cells
21st December 2020,
Biotechnology.
A bioelectrode with the protein complex Photosystem I under irradiation with red light for measurement of the photocurrent response
© Felipe ConzueloPhotosynthetic proteins can convert light energy into other forms of energy. Researchers want to make this technology usable for the industrial production of fuels, for example.
A research team from the Ruhr-Universität Bochum (RUB), together with colleagues from Lisbon, has produced a semi-artificial electrode that could convert light energy into other forms of energy in biosolar cells. The technique is based on the photosynthesis protein Photosystem I from cyanobacteria. The group showed that they could couple their system with an enzyme that used the converted light energy to produce hydrogen. The results were published online in advance in October 2020 in the journal Angewandte Chemie.
For the work, the RUB group consisting of Panpan Wang, Dr. Fangyuan Zhao, Dr. Julian Szczesny, Dr. Adrian Ruff, Dr. Felipe Conzuelo and Professor Wolfgang Schuhmann from the Center for Electrochemistry cooperated with the team consisting of Anna Frank, Professor Marc Nowaczyk and Professor Matthias Rögner from the Chair of Biochemistry of Plants as well as colleagues from the Universidade Nova de Lisboa.
Short-circuit danger
Photosystem I is part of the photosynthesis machinery in cyanobacteria and plants. With the help of light energy, it can separate charges and thus generate high-energy electrons that can be transferred to other molecules, for example to protons for the production of hydrogen.
In earlier work, the Bochum scientists had already used the light-collecting protein complex photosystem I to design electrodes for biosolar cells. For this purpose, they covered an electrode with a photosystem I monolayer. In such monolayers, the photosystems are not stacked on top of each other, but lie side by side in the same plane. Photosystem I, however, usually occurs as a trimer, i.e. three photosystems are always linked together. Since the trimers cannot be packed close together, holes appear in the monolayer, which can lead to short circuits. This impairs the performance of the system. It was precisely this problem that the scientists solved in the present work.
Holes in the photosystem layer plugged
In the cyanobacterium Thermosynechococcus elongatus, photosystem I exists mainly as a trimer. Using a new extraction technique, the researchers were able to isolate additionally monomers from the organism, creating a photosystem I monolayer on the electrode in which the monomers filled the holes between the trimers. In this way, they reduced the short-circuit effects. The system achieved current densities twice as high as a system consisting only of trimers.
To show what the technique could be in principle used for, the scientists coupled it to a hydrogenase enzyme that produced hydrogen using electrons provided by the photosystem. “Future work will be directed toward even more efficient coupling between the photosystem monolayer and the integrated biocatalysts to realize practical biosystems for solar energy conversion,” the authors preview in their publication.
Funding
The work was financially supported by the German Research Foundation within the Cluster of Excellence Ruhr Explores Solvation, short Resolv (EXC2033 – project number 390677874), and within the Research Training Group 2341 “Microbial Substrate Conversion” as well as by the China Scholarship Council.
Original publication
Panpan Wang et al: Closing the gap for electronic short-circuiting: Photosystem I mixed monolayers enable improved anisotropic electron flow in biophotovoltaic devices, in: Angewandte Chemie International Edition, 2020, DOI: 10.1002/anie.202008958
Press contact
Prof. Dr. Wolfgang Schuhmann
Analytical Chemistry – Center for Electrochemistry
Faculty of Chemistry and Biochemistry
Ruhr-Universität Bochum
Germany
Phone: +49 234 32 26200
E-mail: wolfgang.schuhmann@rub.de - Catalytic Activity of Individual Particles
15th December 2020,
Robotic Arm Helps with Analysis.
Two cobalt oxide particles on a carbon nanoelectrode
© T. Quast, RUBAnalyzing nanoparticles individually is a challenge precisely because they are so small. A new technique using electron microscopy and a robotic arm could make the process much easier.
Precious metal-free nanoparticles could serve as powerful catalysts in the future, for example for hydrogen production. To optimize them, researchers must be able to analyze the properties of individual particles. A new method for this has been suggested by a team from the Center for Electrochemistry at Ruhr-Universität Bochum (RUB) and the Institute of Inorganic Chemistry at the University of Duisburg-Essen (UDE). The group developed a method using a robotic arm that allows them to select individual particles under an electron microscope and place them on a nanoelectrode for electrochemical analysis. The method is described in the journal Angewandte Chemie, published online in advance 19 November 2020.
Using a robotic arm to deposit nanoparticles onto electrode
For the studies, the scientists used hexagon-shaped particles of cobalt oxide with diameters of 180 to 300 nanometers, which the Duisburg-Essen team consisting of Professor Stephan Schulz and Sascha Saddeler had synthesized. In the experiment, the particles catalyzed the so-called oxygen evolution reaction. During the electrolysis of water, hydrogen and oxygen are formed, with the limiting step in this process currently being the partial reaction in which the oxygen is formed. More efficient catalysts for the oxygen evolution reaction would simplify the efficiency for electrochemical water splitting under formation of hydrogen. Nanoparticle catalysts are supposed to help with this. Since their catalytic activity often depends on their size or shape, it is important to understand the properties of individual particles in order to find the optimal catalysts.
The Bochum team consisting of Thomas Quast, Dr. Harshitha Barike Aiyappa, Dr. Patrick Wilde, Dr. Yen-Ting Chen and Professor Wolfgang Schuhmann analyzed selected cobalt oxide particles first microscopically, then electrochemically. “Using a movable robotic arm, we can pick out individual nanoparticles under the electron microscope,” Schuhmann explains. “The selected particle, which we then already know microscopically, we place on a tiny electrode to test what it can do as a catalyst.” The researchers then use electrochemical methods to measure its catalytic activity for the oxygen evolution reaction.
High catalytic activity
In this way, the chemists analyzed several individual particles. Since they knew the size and crystal orientation of a particle, they were able to relate the catalytic activity to the number of cobalt atoms. “Here, the particles showed remarkably high activities in the oxygen evolution reaction, and the measured current densities exceeded commercially available alkaline electrolyzers by more than 20 times,” says Stephan Schulz.
“We believe that by applying the proposed methodology, single particle analysis of catalyst materials has finally reached the point of reliable and comparatively simple sample preparation and characterization, which are crucial for establishing structure-function relationships,” the authors write in conclusion.
University Alliance Ruhr
Since 2007, the three Ruhr region universities have been engaged in close strategic cooperation under the umbrella of the University Alliance Ruhr (UA Ruhr). By pooling their strengths, the partner institutions are systematically expanding their output. There are now over 100 cooperations in the fields of research, teaching and administration, all built on the principle of being “better together”. With over 120,000 students and almost 1,300 professors, the UA Ruhr is one of the largest and best-performing hubs for science and technology in Germany.
Funding
The work was funded by the German Research Foundation within the Collaborative Research Center/Transregio “Heterogeneous Oxidation Catalysis in the Liquid Phase” (TRR 247) and the Cluster of Excellence Ruhr Explores Solvation, short Resolv (EXC 2033-390677874), by the European Research Council in the Horizon 2020 Research and Innovation Program (CasCat, 833408) as well as by the Alexander von Humboldt Foundation and the Chemical Industry Fund.
Original publication
Thomas Quast, Harshitha Barike Aiyappa, Sascha Saddeler, Patrick Wilde, Yen-Ting Chen, Stephan Schulz, Wolfgang Schuhmann: Single entity electrocatalysis of individual ‘picked‐and‐dropped’ Co3O4 nanoparticles on the tip of a carbon nanoelectrode, in: Angewandte Chemie International Edition, 2020, DOI: 10.1002/anie.202014384
Press contact
Prof. Dr. Wolfgang Schuhmann
Analytical Chemistry
Center for Electrochemistry
Faculty of Chemistry and Biochemistry
Ruhr-Universität Bochum
Germany
Tel.: +49 234 32 26200
E-Mail: wolfgang.schuhmann@rub.deProf. Dr. Stephan Schulz
Inorganic Chemistry
Center for Nanointegration Duisburg-Essen
Faculty of Chemistry
University of Duisburg-Essen
Germany
Phone: +49 201 18 34635
Email: stephan.schulz@uni-due.de - Nanochip with Quantum Advantage
10th December 2020,
Physics.
The Bochum researchers, here Arne Ludwig, are experts in the production of quantum dots, which can be used to realize qubits - the information units for future quantum computers.
© RUB MarquardThe technology is potentially more powerful than the world's fastest supercomputer.
A Danish-German research team has developed a tiny chip based on quantum technology that - if realized on a larger scale - could surpass the computing power of a classically operating supercomputer. The researchers showed that their nanochip can, in principle, achieve this so-called quantum advantage. Light particles, also called photons, are generated in the chip and can be used as on-the-fly quantum information units. The team from the University of Copenhagen and Ruhr University Bochum reports on the development in the journal Science Advances, published online Dec. 9, 2020.
Quantum advantage through superposition of states
Quantum computers could solve some computational tasks significantly faster than classical computers because they could process information in parallel to a high degree. While a classical computer works with bits that have either the state zero or one, quantum computers would be based on qubits that can assume many different states simultaneously. Research groups and IT companies around the world are working hard to develop a technique that would make the so-called quantum advantage a reality: a state in which a quantum technology can solve a particular computing task faster than the world's most powerful supercomputers.
The team led by Prof. Dr. Peter Lohdahl of the Copenhagen Center for Hybrid Quantum Networks has now unveiled a chip just one-hundredth as thick as a human hair that could achieve the quantum advantage. The nanochip produces stable photons into which researchers can store quantum information. The quality of the individual photons must be so high that they are quantum mechanically indistinguishable, i.e., virtually identical. If enough of these photons are generated - and this is possible with the chip - computing operations can be performed that far exceed the computing power of a classical computer.
The expertise of the Bochum group led by Dr. Arne Ludwig and Prof. Dr. Andreas Wieck from the Chair of Applied Solid State Physics, who are experts in the production of semiconductor structures that can be used to store and read out quantum information, was also crucial to the development.
Practical test requires large financial investment
The newly developed chip has not yet undergone practical testing, so the physicists have not yet used it to solve a computational problem faster than a supercomputer. Conducting such an experiment would far exceed the financial resources of a university. "Put simply, the photons produced by our chip can be compared to the switching states on transistors in classical computers, but with quantum states," says Arne Ludwig. "For the practical test, the chip would now have to be built into a photonic circuit, i.e., wired correctly, so to speak. The technology for this already exists, but a lot of work, time and money would have to be invested in its implementation."
To achieve the quantum advantage, the researchers would need to be able to use their technique to control about 50 of their qubits created in the chip. That mark comes from experiments conducted by Google, which had its quantum computer based on superconducting qubits undergo the field test. In their current work, the Danish-German team used theoretical methods to show that it would be possible to control 50 qubits using the light-based technique. Now they are looking for industry partners who could scale up the chip for practical applications.
Different types of qubits
There are different approaches to developing quantum computers, whose information units can be based on atoms, electrons or photons. Each technique has its advantages and disadvantages. According to scientists, the biggest advantage of the light-based technique is the fact that photonic technologies are already widely used in the telecommunications industry. So when scaling up the technology, it could dock onto existing infrastructure.
Quantum dots from Bochum
Over the past eight years, the Bochum team has continued to develop the manufacturing technology for quantum dots. These are structures in semiconductors that can emit qubits in the form of photons. Together with partners, they designed techniques to load and unload qubits with information in a targeted manner and to be able to transport information over long distances. Because the quantum dots are nearly perfect at emitting single photons, they are ideal for light-based applications.
Funding
This work was supported by the German Federal Ministry of Education and Research (grant numbers 16KIS0867 and Q.Link.X) and the German Research Foundation (Collaborative Research Center/Transregio 160, project number 383065199 and DFH/UFA CDFA-05-06).
Original publication
Ravitej Uppu, Freja T. Pedersen, Ying Wang, Cecilie T. Olesen, Camille Papon, Xiaoyan Zhou, Leonardo Midolo, Sven Scholz, Andreas D. Wieck, Arne Ludwig, Peter Lodahl: Scalable integrated single-photon source, in: Science Advances, 2020, DOI: 10.1126/sciadv.abc8268
Press contact
Prof. Dr. Andreas Wieck
Chair of Applied Solid State Physics
Faculty of Physics and Astronomy
Ruhr University Bochum
Phone: +49 234 32 26726
E-mail: andreas.wieck@rub.deDr. Arne Ludwig
Chair of Applied Solid State Physics
Faculty of Physics and Astronomy
Ruhr University Bochum
Phone: +49 234 32 25864
E-mail: arne.ludwig@rub.de - Light Weakens Magic Nano Clusters
9th December 2020,
Research on Semiconductors.
Model of a (CdSe)13 cluster (yellow/grey) surrounded by organic molecules (blue/white)
© F. Muckel et. al., Nat Commun 11, 4127 (2020), CC 4.0They are known as "magic sized nano clusters" because they have special properties: The particles consist of only a few atoms, but since they are arranged in a special crystal structure, they are extremely stable. Unless you expose them to light. Scientists from the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) have discovered that such materials undergo fundamental changes as soon as they are merely analysed using optical methods. "Nature Communications" reports on the issue.
Junior professor Dr. Franziska Muckel is head of the working group "Electroenergetic Functional Materials" at the chair "Materials of Electrical Engineering”. Her team investigates cadmium selenide particles, which consist of no more than 26 atoms. Yet these atoms are arranged in a crystal structure, i.e. in a regular lattice similar to the symmetrical climbing frames made of ropes and metal on children's playgrounds. This structure renders the particles extremely stable.
In collaboration with the Seoul National University (South Korea) and the Max-Planck-Institut für Eisenforschung in Düsseldorf, UDE's researchers demonstrated that light above a certain wavelength weakens the bonds within these semiconductor nano clusters significantly – a hundred times more than in the same material with much larger dimensions.
Optical analysis methods as standard techniques in semiconductor research thus reach their limits in these dimensions: Instead of merely elucidating material properties, they change the investigated material itself. Since magic nano clusters are an important intermediate step on the way to larger functional particles, this is a decisive discovery.
Muckel, who conducts her research at the NanoEnergieTechnikZentrum (NETZ) on the Duisburg campus, now wants to put the results to practical use: "In the long term, we plan to develop components from similar materials that convert light into charge carriers and could therefore serve as optical sensors."
Original Publication:
F. Muckel, S. Lorenz, J. Yang, T. A. Nugraha, E. Scalise, T. Hyeon, S. Wippermann, G. Bacher
„Exciton-driven change of phonon modes causes strong temperature dependent bandgap shift in nanoclusters“
Nat Commun 11, 4127 (2020)
https://doi.org/10.1038/s41467-020-17563-0Further Information:
Jun.-Prof. Dr. Franziska Muckel, Electroenergetic Functional Materials, +49 203/37 9-3408, franziska.muckel@uni-due.deEditor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de
- Publication in Physical Review Letter
4th December 2020,
On the Trail of the Mysterious Dark Exciton Matter.
Apl. Prof. Dmitri Yakovlev, Prof. Dietmar Fröhlich, Andreas Farenbruch und Prof. Manfred Bayer haben neue Erkenntnisse über Exzitonen erlangt.
© Oliver Schaper/TU DortmundLEDs are the basis for the energy-efficient generation of light: Inside them, electricity creates particles called excitons, which are converted into light. These "bright" excitons have "dark twins", which a research team at TU Dortmund University has now characterized in detail for the first time - and made some astonishing observations in the process. For example, the team was able to detect quantum mechanical phenomena that improve the understanding of interference effects in LEDs.
Today, LEDs are built into smartphones, televisions and lamps and have become an indispensable part of everyday life. Their widespread use was only made possible by the development of the blue light-emitting diode, for which the Nobel Prize in Physics was awarded in 2014. Before that, there were already red and green light-emitting diodes. Together with the blue light-emitting diode, it was now also possible to generate white light.
To generate light, negative and positive electrical charges are injected into a crystal. When two collide, they transform into light and decay. Before that, they enter a bound state. This state corresponds to a new particle called an exciton. Excitons can only have certain energies, which are given by quantum mechanics. Each light-emitting crystal exhibits a specific series of energy states of the excitons, whose values depend on the material. If one wants to optimize this, one needs conclusions about the excitons and their characteristic energies. For the first time, excitons were detected in the material copper oxydul (Cu2O).
Dark and bright excitons
In addition to the bright, light-emitting excitons, there are also dark excitons that cannot decay into light. Via a quantum mechanical interaction, the so-called exchange interaction, their energies differ from those of the light excitons. So far, only the lowest ground state of this dark exciton matter could be observed in all known materials, including copper oxide. According to their name, these states had remained dark and hidden until now.
Now, for the first time, the Dortmund physicists were able to gain a deeper insight into the dark exciton world. For this purpose, strong magnetic fields were used to mix dark and bright excitons. In addition, a special experimental technique was used in which two photons, each with half the exciton energy, are used to excite the dark exciton. When this decays again, a photon is produced which can be observed. Only by this trick the extremely weak signals can be measured at all.
Thus, the research team of TU Dortmund succeeded in observing the six energetically lowest dark excitons and in systematically measuring the exchange energy. On the basis of quantum mechanics, clear differences to atomic physics and its predictions became apparent. Thus, the energies of the dark excitons should be systematically below those of the bright excitons. However, the Dortmund team found an exception, namely the state with the second lowest energy. Here the order is reversed, the bright exciton has a lower energy than the dark one. They were also able to clarify the reason for this: The bright exciton is in strong coupling with another exciton of higher energy, and whenever in quantum mechanics there is such a coupling, the two levels involved repel each other. As a result, the energy of the light exciton is lowered, while that of the dark exciton hardly changes. As a consequence, their order is rotated.
Publication in renowned journal
With this finding, the influence of dark excitons and the possibility to manipulate them can now be better understood. For example, dark excitons can massively interfere with the brightness of a light-emitting diode, for example by causing excitons to accumulate in the lowest-energy dark state. Conversely, information could also be stored in dark excitons, since they do not decay. This opens up new perspectives for their constructive use.
The results were published in the current issue of the renowned journal Physical Review Letters.
Original publication:
Andreas Farenbruch, Dietmar Fröhlich, Dmitri R. Yakovlev and Manfred Bayer: Rydberg Series of Dark Excitons in Cu2O. Physical Review Letters 125, 207402 (2020).
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.207402Contact person for queries:
Andreas Farenbruch
E-mail: andreas.farenbruch@tu-dortmund.de
Experimental Physics II
Faculty of Physics - New Heisenberg Professorship
2nd December 2020,
Interlocked Molecules as Catalysts.
© UDE/Frank PreußNot directly connected, but inseparable: interlocked molecules are interwoven like links in a chain or like a ring on a thread. Professor Jochen Niemeyer is researching how they are applied at the Faculty of Chemistry and the Center for Nanointegration (CENIDE) at UDE. The new Heisenberg Professor of Organic and Supramolecular Chemistry is particularly interested in their use as catalysts.
Interlocked molecules have been known since the last century, but their application is still in its infancy. They consist of several components that are interwoven in space, analogous to the links of a chain or like a ring on an axis closed on both sides. In 2016, the Nobel Prize in Chemistry was awarded for their highly complex production.
At UDE, Professor Niemeyer and his team have been using them for some time for cooperative catalyses, in which two active units work together to control a reaction. "This allows us to produce complex chemical products in a resource-efficient way. As catalysts, the interlocked molecules accelerate the chemical reaction, and at the same time, unwanted byproducts can be avoided," explains the Heisenberg professor. Although this is initially basic research, later application in industrial catalysis is conceivable.
Professor Niemeyer wants to teach his chemistry students as close to applications and research as possible. "I always try to show them how the content is used in industry and research," he says. At the same time, he would like to anchor the research focus of the Faculty of Chemistry, supramolecular chemistry, more firmly in teaching.
After a very good chemistry degree (2000-2005) and an excellent PhD (2009) at the University of Münster, Jochen Niemeyer did research at Emory University (USA) in 2004 and at Nagoya University (Japan) in 2006/07. In 2010, he was a postdoc at the University of Oxford for one year, and from 2011 to 2014, he was a laboratory manager in innovation management at Evonik Industries AG. At UDE, he has headed a junior research group in organic chemistry since 2014. His research and teaching have received several awards.
Further information:
Prof. Dr. Jochen Niemeyer, Organic Chemistry, Tel. 0201/18 3-3148, jochen.niemeyer@uni-due.deEditorial office: Dr. Alexandra Nießen, Tel. 0203/37 9-1487, alexandra.niessen@uni-due.de
- Andronescu on the Advisory Board
27th November 2020,
Support for Young Scientific Careers.
© UDEMaterials Chain member Jun-Prof. Corina Andronescu from the Faculty of Chemistry of University of Duisburg-Essen (UDE) will join the "Early Career Advisory Board" of ChemElectroChem, a high-ranking journal for pure and applied electrochemistry, as of January 1, 2021. The aim is to promote young scientists and to involve them in publication processes at an early stage.
To serve on the editorial board of an important journal usually requires that you have already made a name for yourself in the scientific community. However, this is often not the case, especially in the early stages of a career. "This is why I find the ChemElectroChem initiative very innovative," praises Andronescu. Through the so-called Early Career Advisory Board, young researchers can be involved in the activities of a scientific journal at an early stage and thus gain important experience in scientific publishing already in this career phase. In addition, special issues can be initiated or other young researchers can be recommended for the review process. "I am honored and delighted to be able to serve the scientific community already in this early career phase," summarizes the expert in electrochemical catalysis.
Andronescu's junior professorship is part of the German government's program for the promotion of young scientists (WISNA), which aims to offer young scientists a transparent and plannable path to a lifetime professorship. To date, 468 of these "tenure-track professorships" have been funded throughout Germany, 23 of them at the UDE. At the Duisburg campus, she conducts research on electrochemical catalysis both at the NanoEnergieTechnikZentrum (NETZ) and the Zentrum für BrennstoffzellenTechnik (ZBT). Her project MatGasDif, short for "Nanomaterials as a basis for gas diffusion electrodes for highly selective CO2 reduction", is funded by the Federal Ministry of Education and Research with 1.4 million euros for five years.
Editors: Sarah Heuser, sarah.heuser@uni-due.de, Steffi Nickol, steffi.nickol@uni-due.de
- Collaborative Research Center Extended
27th November 2020,
Success for UDE and RUB. Read original article
Fully integrated digital microbolometer infrared image sensor with chip-scale vacuum package.
© Fraunhofer IMSThe SFB MARIE (Mobile Material Characterization and Location by Electromagnetic Scanning) has been extended. This program, which develops the fundamentals for mobile mini-material detectors, will be funded with 13.7 million euros for a second phase from 2021 to 2024. UDE and the Ruhr-Universität Bochum are working together on this project.
Since 2016, this CRC/Transregio has been researching the basic principles for a mobile highly sensitive mini detector. The device will one day be able to determine the material properties of almost any object, even if it is hidden behind a wall. This will also make it possible to detect people in contaminated rooms or stewing cables inside walls. To do this, the detector must cover very high frequencies down to the terahertz range.
In the first funding phase, compact high-performance terahertz transmitters and receivers were designed, measured and finally realized in the disciplines of electronics, photonics and micromechanics. According to the international SFB reviewers, these are among the world's best. In the second funding phase starting in January, these detectors will be "mobile", i.e. particularly energy-efficient and lightweight. They will thus be suitable for numerous applications, including integration into a smartphone.
MARIE is headed by Prof. Thomas Kaiser (spokesperson), head of the UDE Department of Digital Signal Processing, and Prof. Ilona Rolfes, head of the RUB Chair of High Frequency Systems. The University of Wuppertal, TU Darmstadt and the Fraunhofer Institutes for Microelectronic Circuits and Systems (IMS/Duisburg) and for High-Frequency Physics and Radar Technology (FHR/Wachtberg) are also involved.
Further information:
Prof. Dr. Thomas Kaiser, Digital Signal Processing, Tel. 0203/37 9-1873, thomas.kaiser@uni-due.de - Green Methanol Production in Container Format
24th November 2020,
Chemistry.
Methanol is an important raw material for the chemical industry. Up to now, it has mostly been obtained from fossil natural gas. A team with RUB participation wants to change this.
© Alina Gawel
A research association is developing a sustainable and scalable process for methanol production.
Methanol is produced from fossil natural gas at a rate of more than 100 million tons per year. In view of the Paris Climate Agreement, the associated CO2 emissions are unacceptable. This aspect is addressed by the research project "E4MeWi" under the leadership of Creative Quantum: Over the next three years, an interdisciplinary team of chemists and engineers will develop a container-sized chemical plant that will produce methanol from water, carbon dioxide and renewable energies in a highly efficient manner. This will enable small and medium-sized companies as well as regional suppliers to produce methanol in a decentralized and environmentally friendly way in a few years.
The research association consists of the startups Creative Quantum and Ineratec as well as the Leibniz Institute for Catalysis and the Ruhr-Universität Bochum and Chemiepark Bitterfeld-Wolfen. The project is being funded by the Federal Ministry of Economics and Energy with a total of 2 million euros for three years from November 1, 2020.
Using CO2 emissions and electricity from renewable energies
The abbreviation E4MeWi stands for energy-efficient renewable energy-based methanol economy. The planned container-sized chemical plant is to demonstrate that methanol can be produced from sustainable sources by orders of magnitude faster and more energy-efficiently than before. A further goal of the project partners is to design the technology in such a way that methanol can be produced at competitive prices in places where cheap electricity meets local CO2 emissions. In the vision of the project partners, wind power and waste incineration plants or solar energy and biogas plants could thus be brought together for a new added value, resulting in a sustainable source of raw materials for the chemical industry. The mobility sector is another target market for green methanol, which can be used as a fuel additive or for fuel cells.
Dr. Marek Checinski, CEO and co-founder of Creative Quantum from Berlin, is one of the inventors of the process innovations implemented in the project. His company uses computers to calculate the chemical and physical properties of substances and materials and elucidates chemical reactions and processes in detail. From his experience, "chemists are often skeptical and doubt that computers and modern algorithms can be used to evaluate and optimize completely new processes from scratch. Methanol is one of the most important chemicals on which we wanted to demonstrate this once". He developed the new capture and hydrogenation approach. Creative Quantum will now further improve this process in virtual space. Modern methods such as genetic algorithms and machine learning will be used.
From the RUB, the team around Prof. Ulf-Peter Apfel from Inorganic Chemistry is involved. His group is responsible for catalyst and reactor development for the electrochemical reduction of CO2 to synthesis gas.
Press contact
Dr. Alexander Janz
Creative Quantum
Phone: +49 30 9599 911 88
e-mail: kontakt@e4mewi.deProf. Ulf-Peter Apfel
Inorganic chemistry I
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 21831
e-mail: ulf.apfel@rub.de - Novel Quantum Dots Facilitate Coupling to Quantum Memory Systems
12th November 2020,
Physics.
Julian Ritzmann from the Bochum Chair for Applied Solid State Physics
© RUB, MarquardResearchers from Basel and Bochum have realised a key element of quantum communication at the edge of the visible spectrum. So far, that was only possible in the near-infrared range.
Researchers at the University of Basel and Ruhr-Universität Bochum have realised quantum dots – tiny semiconductor nanostructures – that emit light close to the red part of the spectrum with ultra-low background noise. Quantum dots might one day constitute the basis for quantum computers; the light particles, also called photons, would then serve as information carriers. Quantum dots with adequate optical properties had previously only been obtained for photons with wavelengths in the near-infrared range. Now, the researchers have succeeded in creating low-noise states at wavelengths between 700 and 800 nanometres, i.e. close to the visible red range. This would, for example, enable coupling to other photonic systems. They outline their findings in the journal “Nature Communications” from 21 September 2020.
Different wavelengths required
Systems for quantum communication require photons of different wavelengths. For communication over long distances, the main requirement is to avoid signal losses; wavelengths around 1,550 nanometres can be used for this purpose. For short distances, on the other hand, photons are needed that can be detected as effectively as possible and connected to other quantum memory systems. This would be possible with red light, or more precisely with wavelengths between 700 and 800 nanometres. Currently available photon detectors have their highest sensitivity in this range. Moreover, light particles of this frequency could be coupled with a rubidium storage system.
In order for information in a quantum system to be precisely encoded, manipulated and read out, stable optical emission is crucial. This is exactly what the researchers have now achieved for photons near the visible red range.
Lower aluminium content is the key to success
The project was a collaborative venture between a team of young physicists led by Professor Richard Warburton from the Basel-based Nano-Photonics Group and Professor Andreas Wieck, Dr. Arne Ludwig, Dr. Julian Ritzmann and colleagues from the Chair for Applied Solid State Physics in Bochum. The researchers converted the quantum dots in a semiconductor made of gallium arsenide. Since the system has to be cooled with liquid helium, it operates at low temperatures of minus 269 degrees Celsius.
One of the main challenges was to design a diode with gallium-arsenide quantum dots that reliably emits photons at these low temperatures. The Bochum-based team produced aluminium-gallium-arsenide layers with a lower aluminium concentration than usual, which improved the layers conductivity and stability. The Nano-Photonics team then used this material for the experiments in Basel.
Coupled system in progress
In the next step, the researchers are planning to combine the newly developed quantum dots with a rubidium quantum memory device. Such hybrid structures would be a first step towards practical applications in future quantum communication network.
Funding
The project was funded by the European Union as part of the Horizon 2020 Programme (Marie Skłodowska-Curie Grants no. 721394/4PHOTON and 840453/HiFig), by the Swiss National Science Foundation as part of the National Centre of Competence Research QSIT and the project with the funding number 200020_156637, the German Research Foundation as part of the projects at Collaborative Research Centre/Transregio 160 and project 383065199, the Franco-German University in the project DFH/UFA CDFA05-06, as well as the Federal Ministry of Education and Research (Q.Link.X 16KIS0867).
Original publication
Liang Zhai, Matthias C. Löbl, Giang N. Nguyen, Julian Ritzmann, Alisa Javadi, Clemens Spinnler, Andreas D. Wieck, Arne Ludwig, Richard J. Warburton: Low-noise GaAs quantum dots for quantum photonics, in: Nature Communications, 2020, DOI: 10.1038/s41467-020-18625-zPress contact
Chair for Applied Solid State Physics
Faculty of Physics and Astronomy
Ruhr-Universität BochumDr. Arne Ludwig
Phone: +49 234 32 25864
Email: arne.ludwig@rub.deDr. Julian Ritzmann
Phone: +49 234 32 25805
Email: julian.ritzmann@rub.deProf. Dr. Andreas Wieck
Phone: +49 234 32 26726
Email: andreas.wieck@rub.deNano-Photonics Group
Department of Physics
University of BaselProf. Dr. Richard Warburton
Phone: +41 61 207 3560
Email: richard.warburton@unibas.chLiang Zhai
Phone: +41 61 207 3866
Email: liang.zhai@unibas.ch - Basic Research for IT of the Future
10th November 2020,
Research Team Achieves Strong Coupling of Sound and Spin Waves in Magnets.
Dmytro Yaremkevych, Serhii Kuktaruk, Prof. (apl.) Dmitri Yakovlev, Felix Godejohann, Dr. Alexey Scherbakov and Prof. Manfred Bayer have published their research results in the renowned journal Physical Review B.
© Martina Hengesbach/TU DortmundSince electronic data processing will foreseeably reach its limits, alternative methods for the information technology of the future are in demand. In magnetic materials, there are two types of excitations that could perspectively serve as efficient information carriers: the vibrations of the crystal lattice and the oscillations of the magnetic moment. Under the leadership of Dr. Alexey Scherbakov from the Faculty of Physics at TU Dortmund University, an international group of scientists from five different research centers has now shown that these two excitations can be made even more efficient by strong coupling.
In our everyday lives, we receive, process and send huge amounts of data. Classical electronics, which master data processing with the help of electric charge, has made enormous progress in the past, as can be seen in the example of smartphones. Today, however, it is facing major challenges, as energy efficiency requirements are increasing and electronics cannot become infinitely more compact and more powerful at the same time. For this reason, researchers around the world are looking for alternative ways to transfer and process data, especially in quantum computers and neural networks.
There are two possible information carriers in magnetic components that could be used in energy-efficient devices in the future: on the one hand, the atomic vibrations in the crystal lattice and, on the other, the oscillations of the magnetic moment. As sound or spin waves, they exhibit behavior similar to that of water waves. Since they propagate without any electrical charge, they do not experience any electrical resistance that would cause losses and heat up the processor - as in conventional devices. Moreover, the waves oscillate at frequencies of up to 100 GHz - which is much higher than the clock frequencies of a few GHz in modern processors - while their wavelengths are well below 1 millionth of a meter. Devices that use this type of data processing in the future could therefore be considerably faster, smaller and more energy-efficient.
Simultaneous sound and spin wave
However, to be able to exploit these advantages, reliable mechanisms for data handling must first be developed. This can be done, for example, by taking advantage of the fact that sound waves can trigger spin waves and vice versa, so that these two waveforms can be converted into one another. However, this requires the strongest possible coupling between the two waves.
The international research team from Germany, Russia, Ukraine and Great Britain has now succeeded for the first time in achieving a strong coupling between a sound wave and a spin wave with identical frequencies in a spatial structure similar to a computer chip. They observed the mutual transformation of the two excitations with a time resolution far below a billionth of a second. During the periodic conversion, a new excitation is created that is simultaneously both a sound wave and a spin wave.
This observation could be used for technological purposes in the future: Because by coupling spin waves with sound waves, they can be transported over greater distances - something that is necessary for the coding and transmission of high-frequency data.
"Since our first work in the field of ultrafast magnetoacoustics 10 years ago, we have tried to directly observe this strong coupling. Bringing together the knowledge of all cooperation partners involved was crucial for this success: From Nottingham we received magnetic samples in optimal quality, which formed the basis for the investigations in Dortmund. Our observations were explained and supported by sophisticated theoretical model calculations from Saint Petersburg and Kiev," says Dr. Alexey Scherbakov. Professor Manfred Bayer, Rector of the TU Dortmund University and member of the research team, adds: "The contribution of Raith GmbH, one of the world's leading suppliers of equipment for nanofabrication, should also not go unmentioned: They produced nanogrids of the highest quality for us".
Original publication:
F. Godejohann, A. V. Scherbakov, S. M. Kukhtaruk, et al: Magnon polaron formed by selectively coupled coherent magnon and phonon modes of a surface patterned ferromagnet. Physical Review 102, 144438 (2020)
Contact person for further questions:
Alexey Shcherbakov
e-mail: alexey.shcherbakov@tu-dortmund.de
Experimental Physics II
Faculty of Physics
Felix Godejohann
e-mail: felix.godejohann@tu-dortmund.de
Experimental Physics II
Faculty of Physics - Innovation Prize for Anna Grünebohm
26th October 2020,
ICAMS researcher wins in young talent category. Read original articleICAMS junior professor Anna Grünebohm, was awarded the Innovation Prize of the State of North Rhine-Westphalia in the young talent category. Her research focuses on ferroelectric materials, which are able to cool themselves down under certain conditions or to generate electricity from movement. Her cross-scale computer simulations contribute to a fundamental understanding of the interaction between a material, its microstructure and its functional properties. The prize is endowed with 50,000 euros. Congratulations, Anna!
© RUB, Marquardhttp://www.icams.de/content/departments/scalebridging-simulation-of-functional-composites/
- Better Anode Material for Lithium Ion Batteries
15th October 2020,
2.3 Million € for Battery Project by UDE and Evonik.
Amorphous silicon/carbon particles (image taken by transmission electron microscope).
© ICAN/Dr. Hans OrthnerIt is expected to be market-ready by 2023: Anode material for lithium ion batteries, leading to more powerful energy storage systems. The material has already been tested in the laboratories of the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE). Since September 1, the German Federal Ministry of Economics is funding UDE with almost 1.7 million Euro to further develop the synthesis process in a joint project with Evonik and transfer it to industrial scale.
To date, graphite is used as the anode material in lithium-ion batteries, but its storage capacity and ability for rapid charging have almost reached the limit. A promising alternative was developed by UDE and Evonik in the synthesis facilities of the NanoEnergieTechnikZentrum (NETZ) at the Duisburg campus: The composite of carbon and silicon has a much higher capacity in the same volume, long-term stability and can be charged fast. "No project partner knows of anything comparable," says Prof. Dr. Hartmut Wiggers, expert for the gas phase synthesis of nanomaterials. The composite easily provides the capacity of 1.5 Ah/g that industry is looking for.
The manufacturing and processing methods – already established in the laboratory – will now be developed and transferred to the industrial scale. Two further groups, led by Prof. Doris Segets and Prof. Andreas Kempf, are involved in this project. Together, they cover topics related to process design, particle characterization and modeling as well as particle processing into pastes and printing of the anode material on copper foil.
Evonik uses the flow models and the experiments of the UDE experts for its own industrial-scale pilot plant. "Our first goal is to ensure the correct composition and shape of the particles at the industrial scale. This will allow us to offer our customers tailor-made solutions“, explains Dr. Julia Lyubina, the project lead at Evonik.
The Federal Ministry for Economic Affairs and Energy is funding the joint project "HOSALIB - High-performance silicon-carbon composite as anode material for lithium-ion batteries" for three years with a total amount of 2.3 million Euro (grant number 03EI3027 A/B).
Further Information:
apl. Prof. Dr. Hartmut Wiggers, Institute for Combustion and Gas Dynamics – Reactive Fluids, +49 203/37 9-8087, hartmut.wiggers@uni-due.deEditor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de
- Flexible Light Emitting Elements in 2D
14th October 2020,
Scalable Growth Process.
Foil with 1 cm edge length, containing four emitter elements with one of them depicted in operation in the inset.
(Source: Andrzejewski et al., Advanced Optical Materials 2020, 2000694, Published by Wiley-VCH, Weinheim)If 80,000 of them were piled on top of each other, the stack would only be as high as a flat sheet of paper. Scientists from the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) and cooperation partners have developed a layer of tungsten disulfide that is just as thin as three atomic layers – and it is luminous, flexible and also withstands external influences. Several square centimeters of this layer have already been embedded in structural components, but the manufacturing process is scalable beyond that, the trade journal Advanced Optical Materials reports.
The wafer-thin luminescent layer grows on a sapphire base, is then carefully removed with the aid of a lacquer and transferred to the carrier film. The lacquer is then dissolved. In broad terms, this is the manufacturing process the project partners from UDE, RWTH Aachen University and AIXTRON used to develop entire devices from the two-dimensional material. The method can be scaled to much larger areas using the same material and the same device architecture, and this is what makes it interesting from an industrial point of view.
Change the bending to change the light
Led by UDE's Professor Gerd Bacher, lighting elements were created that combine the advantages of different component concepts: The inorganic tungsten disulfide layer is less susceptible to harmful environmental influences such as oxygen or moisture and is also long-term stable. Due to the flexible design, the structure adapts to any shape. But the flexibility has even another advantage: if the film is bent, the crystal lattice of the luminous layer is distorted and the wavelength of the emitted light – and thus the color of the light – changes. Although this difference is not visible to the naked eye, it is easy to detect with measuring instruments.
"This is what makes the elements interesting as sensors, for instance”, explains Dr. Tilmar Kümmell from the Bacher working group. "We think they could be used to detect deformation or distortions.” On the other hand, the precise bending of the film would also make it possible to select a specific wavelength for the emitted light.
Original Publication:
D. Andrzejewski, R. Oliver, Y. Beckmann, A. Grundmann, M. Heuken, H. Kalisch, A. Vescan, T. Kümmell, G. Bacher
„Flexible large-area light-emitting devices based on WS2 monolayers“
Advanced Optical Materials 2020, 2000694
https://doi.org/10.1002/adom.202000694Further Information:
Dr. Tilmar Kümmell, Electronic Materials and Nanostructures, +49 203/37 9-3403, tilmar.kuemmell@uni-due.deEditor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de
- First Interdisciplinary Conference
12th October 2020,
Jointly Promoting Catalysis Research.
© CENIDECatalysis initiates central processes of our entire life on earth - from enzyme catalysis in metabolic processes in all organisms to natural photosynthesis and the production of synthetics and environmentally friendly energy sources. Scientists in four Collaborative Research Centres (CRCs) of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) are currently investigating how these fundamental and at the same time diverse processes of chemical catalysis work exactly and how their principles can be used for sustainable value creation.
In order to set new research impulses and create synergies in the field, the four DFG-funded Collaborative Research Centres have now organised the first joint CataLysis conference. Around 170 researchers from Germany and Austria presented their latest research findings in a joint online conference from September 30th to October 1st, 2020 and initiated new collaborations.
The participants presented their research topics in 16 lectures and 65 poster contributions. The spectrum ranged from homogeneous and heterogeneous catalysis, thermal catalysis and photocatalysis to (photo-) electrochemistry. The researchers also exchanged the latest findings on the methodological and theoretical characterisation of catalysis processes and on new materials and methods. After the sessions there was the possibility to meet and discuss with the speakers in a virtual room. Other virtual networking areas such as the Coffee Point or the Snack Bar offered additional opportunities to exchange ideas and initiate cooperation.
The speakers of the Collaborative Research Centres closed the conference with a positive summary: "We are thrilled to see the different and interesting developments that have emerged within catalysis research," said Prof. Michael Buchmeiser, spokesperson of CRC 1333. And Prof. Malte Behrens, spokesperson of CRC/TRR 247, added: "In order to be able to create synergies and make catalytic processes usable for important applications in the future, it is necessary to continue to illuminate this complex and multifaceted research area from all sides." Prof. Sven Rau, spokesperson of the CRC/TRR 234, is particularly pleased about the high participation of doctoral students who used this event for discussion and networking, underlining the importance of training for the sustainable catalysis research. In summary, Prof. Christian Jooss, spokesperson of CRC 1073, adds that the common goal is to link the methodologies and approaches even more strongly in the future than in the past and beyond the boundaries of the respective Collaborative Research Centres.
The spectrum of the field of catalysis is reflected in the topics of the Collaborative Research Centres:
- CRC 1333: "Molecular Heterogeneous Catalysis in Confined Geometries"
- CRC/TRR 247: "Heterogeneous Oxidation Catalysis in the Liquid Phase - Materials and Mechanisms in Thermal, Electro- and Photocatalysis"
- CRC 1073: "Atom Scale Control of Energy Conversion"
- CRC/TRR 234: "CataLight - Light-driven Molecular Catalysts in Hierarchically Structured Materials: Synthesis and Mechanistic Studies"
Edited by: CRC 1333, CRC/TRR 247, CRC 1073 and CRC/TRR 234
- Materials for Laser Additives Manufacturing
8th October 2020,
International Conference.
Castle Montabaur
© WikipediaBringing together the fields of laser additive manufacturing and materials science is the goal of the international conference "New Frontiers in Materials Design for Laser Additive Manufacturing", which will take place from May 25 to 28, 2021, at the Hotel Schloss Montabaur. High-ranking keynote speakers will present and discuss current developments. Registration deadline for the conference organized by the Center for Nanointegration Duisburg-Essen (CENIDE) is December 6.
The conference serves as a stimulating forum for international knowledge exchange and closer cooperation between scientists working in these fields. Inspired by Gordon Research Conferences, the conference venue was chosen for its scenic and isolated location to promote an informal community atmosphere. Accordingly, there will be no parallel sessions and in addition to the focused scientific presentations and posters there will be ample time for discussion.
The international conference is organized and financially supported by the priority program SPP 2122 "Materials for Additive Manufacturing", which is funded by the German Research Foundation (DFG), and by the Center for Nanointegration Duisburg-Essen (CENIDE).
Further Information and Registration:
https://udue.de/confmat4am
Prof. Stephan Barcikowski, Coordinator SPP 2122, +49 201 18-33150, stephan.barcikowski@uni-due.deEditor: Tobias Teckentrup, +49 203 37-98178, tobias.teckentrup@uni-due.de
- Catalyst Material from the Laser Lab
2nd October 2020,
Industrial Relevance Proven.
From particle production to the final catalyst (schematic diagram)
© CENIDEIn catalysts, more surface area usually equals more activity. And hardly anything offers more surface than structures made of nanoparticles. Scientists from the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) have shown that it makes sense in economic terms to produce catalytically highly active particles by laser. Not only are they extremely pure, but even at low temperatures they are more efficient than their conventionally produced counterparts. This has been demonstrated in tests conducted by an industrial partner.
Exhaust gases from the diesel engine usually pass a catalytic converter consisting of platinum and palladium particles on an alumina carrier. The particles are smaller than 10 nanometers in diameter and have so far mainly been produced in a wet-chemical process, i.e. in a multi-step process that has to be optimized for each composition. Tests with new materials are therefore time-consuming and expensive.
Laser ablation, on the other hand, makes it possible to produce highly pure nanoparticles from a solid in one step. In this process, a laser vaporizes material from the surface of a platelet with ultra-short pulses. The platelet is made of the selected raw material and lies in a liquid. The fragments then assemble into nanoparticles. That's it.
The former disadvantage of the method: Until now, the output of the desired particle size was limited. But Dr. Sven Reichenberger from Technical Chemistry I and his team found a solution: "We placed the focus point of the laser slightly above the platinum-palladium plate in the solution." In this way, more than one gram per hour in the desired size can be produced selectively. The scientists who work at the NanoEnergieTechnikZentrum (NETZ) have thus exceeded the decisive limit where the laser method is more economical than the wet chemical method due to the low running costs. The trade magazine "Nanomaterials" covers this in its current issue.
Better Performance Even at Lower Temperatures
Umicore as industrial partner has tested the resulting particles under realistic conditions: Even at low temperatures the catalyst shows a much higher activity than the classic product. Moreover, it converts carbon monoxide equally well and nitrogen oxides even better into ecologically safe products.
"This was our milestone to prove the industrial relevance of the method," says Reichenberger. "Now we will test further materials."
Original Publication:
S. Dittrich, S. Kohsakowski, B. Wittek, C. Hengst, B. Gökce, S. Barcikowski, S. Reichenberger
„Increasing the Size-Selectivity in Laser-Based g/h Liquid Flow Synthesis of Pt and PtPd Nanoparticles for CO and NO Oxidation in Industrial Automotive Exhaust Gas Treatment Benchmarking“
Nanomaterials 2020, 10(8), 1582
https://doi.org/10.3390/nano10081582Further Information:
Dr. Sven Reichenberger, Technical Chemistry I, +49 203/37 9-8116, sven.reichenberger@uni-due.de - Entangled Catalysts
24th September 2020,
Interlocked Molecules Provide High Product Selectivity.
Schematic representation of the interlocked molecules. Due to the flexible connection of the two components, the shape of the active center can adapt during the reaction
© Niemeyer, CENIDEThey are inseparable, but not rigidly connected: Mechanically interlocked molecular architectures have only recently been discovered. They can look like two connected chain links or a ring on an axis closed on both sides, for example. Chemists from the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) have now successfully tested them as cooperative catalysts for the first time. Two renowned trade journals have reported on this.
Nowadays, more than 90 percent of all chemical products are obtained by using catalysts. The development of new catalytically active systems is therefore a highly topical field of research. One particularly promising approach is cooperative catalysis, a process in which two active units work together to manage a reaction.
The team of PD Dr. Jochen Niemeyer from Organic Chemistry has now investigated the value of interlocked molecules for this application for the first time. It was not until 2016 that the Nobel Prize in Chemistry was awarded for the production of such highly complex molecules.
Niemeyer's group produced catenanes (chain links) and rotaxanes (ring on axis) and placed active centers on both components. It turned out that this arrangement was ideal for cooperative catalysis: The components can actively adapt during the reaction and position their active centers in the best possible way. "Like a wrench that adjusts itself," Niemeyer puts it.Pure Products by Active Adaptation
Catenanes and rotaxanes both exhibited high product selectivity, which is not the case without the interwoven structure – a decisive advantage for sectors such as the pharmaceutical industry. "Because this means that the result is a single, pure product, not a mixture," the chemist explains.
Theoretical and spectroscopic studies in cooperation with the working groups of Prof. Stefan Grimme from Bonn and Prof. Ruth Gschwind from Regensburg confirmed the cooperative behavior. The results of these studies were published in two scientific articles in "Angewandte Chemie International Edition" and "Chemical Science".
Niemeyer's group now wants to investigate whether and how interlocked molecules with several active centers can be used to potentially realize various reactions with a single catalyst material to obtain different but highly pure products.
Original Publications:N. Pairault, H. Zhu, D. Jansen, A. Huber, C.G. Daniliuc, S. Grimme, J. Niemeyer
“Heterobifunctional Rotaxanes for Asymmetric Catalysis”
Angew. Chem. Int. Ed. 2020, 59, 5102 –5107
https://doi.org/10.1002/anie.201913781D. Jansen, J. Gramüller, F. Niemeyer, T. Schaller, M.C. Letzel, S. Grimme, H. Zhu, R.M. Gschwind, J. Niemeyer
„What is the role of acid–acid interactions in asymmetric phosphoric acid organocatalysis? A detailed mechanistic study using interlocked and non-interlocked catalysts“
Chem. Sci. 2020, 11, 4381-4390
https://doi.org/10.1039/D0SC01026JFurther Information:
PD Dr. Jochen Niemeyer, Organic Chemistry, +49 201/18 3-3148, jochen.niemeyer@uni-due.de
Editor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de - Raw Materials from Waste
23rd September 2020,
Successful Transfer to Industrial Scale.
High-alloyed steel chips after cleaning, ready for reuse in the plant.
© RHM Rohstoff-Handelsgesellschaft mbHRecovering raw materials from contaminated metal chips and thus reusing valuable materials: This sustainable resource efficiency is promised by the deoiling plant, which was developed by University of Duisburg-Essen (UDE) and regional project partners and has now been put into operation in Herne. The process, whose implementation was funded by the Federal Ministry of Education and Research, requires up to 40 percent less energy than other methods.
Anyone who processes metals uses cooling lubricants and oils for this purpose. This reduces friction between the workpiece and the tool, while at the same time dissipating the heat generated and the chips produced during machining. "The chips contain the same metals as the finished product," says UDE Professor Rüdiger Deike from the Institute of Metal Technologies (ITM) and explains: "However, they are contaminated by the lubricants and oils, which means they lose a lot of their value. And yet the alloying elements are often expensive raw materials of strategic economic importance".
For five years, Deike's team, together with the Institute for Energy and Environmental Technology (IUTA) and the industrial partners RHM Rohstoff-Handelsgesellschaft (Mülheim) and Federal-Mogul Burscheid GmbH (now TENNECO), has been investigating how the chips can be economically returned to the material cycle - on an industrial scale.
The result is a deoiling process in which the chips are washed with a mixture of water and surfactants in a multi-stage process and then dried in the cycle. The water is also cleaned and reused. Compared to previous processes, this reduces energy consumption by around 40 percent and CO2 emissions by a good two thirds.
Deoiling is more difficult in the case of waste produced during metal grinding. "The particles are more difficult to separate from the oil because of their smaller grain size," says Deike. However, the scientists have already developed a process on a pilot plant scale for this purpose as well, with which quantities of 100 kg per hour can be deoiled.
The project "COMPASS - Continuous Oil and Metal Recovery Process Plant for Sludges and Chips" was funded by the Federal Ministry of Research with 1.7 million €.
Further information:
https://www.uni-due.de/mus/kompass.php
Prof. Dr.-Ing. Rüdiger Deike, Institute for Metal Technologies, Tel. 0203/37 9-3455, ruediger.deike@uni-due.de - Double Honor for Materials Researchers
22nd September 2020,
Prizes Awarded.
Prof. Gunther Eggeler
© RUB, KramerTwo of this year's awards in materials science go to Bochum.
Two materials scientists from Bochum have received a prestigious award from the German Society for Materials Science (DGM) for outstanding pioneering work and excellent research achievements. Prof. Michael Pohl was honored as a DGM pioneer, Prof. Gunther Eggeler even received the highest award of the DGM with the Heyn coin. Due to the corona pandemic, the annual meeting of the society with the award of the prize winners took place virtually on September 21, 2020.At Ruhr-Universität Bochum (RUB), the joy about the double award is great. "The fact that the DGM awards two of its coveted prizes in a single year to researchers at one location is a very special distinction and honor for the RUB," says Prof. Alexander Hartmaier, Director of the Interdisciplinary Centre for Advanced Materials Simulation. "At the same time, it encourages us, especially with such high-ranking researchers in our rows, to further expand our internationally visible research focus in the future with a new bachelor's degree program in materials science.
About the award winner
Gunther Eggeler has received the highest award of the DGM with the Heyn commemorative coin. Named after the first chairman of the DGM, Emil Heyn, it is awarded for those achievements in the field of materials science and materials engineering which have led to significant progress in scientific, practical or economic terms. Eggeler will be honored in particular for his outstanding research work on shape memory and high-temperature alloys and for his extraordinary commitment to materials research in Germany. As with the other prizes it awards, the DGM also wants to use the Heyn commemorative coin to draw attention to excellent developments in the field.
Pressekontakt
Dr. Iris Bertozzi
PR und Internationalisierung
Fakultät für Maschinenbau
Ruhr-Universität Bochum
Tel.: +49 234 32 27265
E-Mail: IB-Dekanat-MB@rub.de - Award for German-Russian Cooperation
15th September 2020,
Tailor-made Miniature Solutions Against Cancer.
Electron microscopic image of magnetite gold nanoparticles for theranostics.
© Beilstein J. Nanotechnol. 2018, 9, 2684-2699Their nanoparticles of gold and magnetite have been specially developed for the diagnosis and therapy of tumors: Physicists from the Center for Nanointegration (CENIDE) at University of Duisburg-Essen (UDE) and Moscow colleagues will be honored for their successful collaboration on September 15.
"Theranostics" is a portmanteau word combining "therapy" and "diagnostics" and is of crucial importance in medicine: In the project that has now received the award, it refers to the potential applications of the particles, which are only 25 nanometers in size and are injected into affected body regions of patients. Using computer tomography or magnetic resonance imaging, tumor tissue can thus be detected and then targeted in the next step - with the same particles. The combination of precious metal and mineral offers several possibilities; for example, magnetite can be heated by an alternating magnetic field. In doing so, it heats up so strongly that it destroys the surrounding tumor. Healthy tissue remains unharmed and the biocompatible particles are later broken down by the body.
"In contrast to particles that are already commercially available, our particles are optimized for precisely this benefit," says UDE physicist private lecturer Dr. Ulf Wiedwald. Now the cooperation between him and his colleague Prof. Maxim Abakumov from the Russian National University of Science and Technology MISiS is being honored in the category "top-level research".
The cooperation started with Wiedwald's guest professorship in Moscow in 2017/18. "Since then, we have jointly published four papers in renowned journals in the short time available," says the physicist.
The award is presented within the "German-Russian Year of University Cooperation and Science 2018-2020", which is organized by the German Academic Exchange Service (DAAD) and the National University of Science and Technology.
Further information:
Private lecturer Dr. Ulf Wiedwald, experimental physics, Tel. 0203/37 9-2633, ulf.wiedwald@uni-due.de - Tuning Nanoparticles for Green Catalysis
3rd September 2020,
ERC Grant.
Kristina Tschulik is funded by the European Research Council.
© Photostudio-4everKrsitina Tschulik's team is studying individual nanoparticles. They are to become models for optimized catalysts.
In the search for alternatives for precious metal-based catalysts, the research team has considered nanoparticles based on transition metals. To be able to design them optimally, their catalytic activity must be analyzed as a function of their properties. This is the focus of the project "Microfluidic Tuning of Individual Nanoparticles to Understand and Improve Electrocatalysis", or Miticat for short, by Prof. Kristina Tschulik. The holder of the Chair of Analytical Chemistry II at Ruhr-Universität Bochum (RUB) is supported by a Starting Grant from the European Research Council.Two identical particles are rare
Two obstacles currently stand in the way of the smart design of such catalytically active nanoparticles. First, almost all particles are slightly different. Measuring the activity of such a disparate ensemble yields an average value that says little or nothing about the best candidates. Secondly, the effects of additives are unknown, which are necessary for the currently common investigations of catalytic processes with such materials.
Kristina Tschulik and her team have already succeeded in studying individual nanoparticles without additives. "Nevertheless, we have not yet been able to derive a full relationship between properties and activity, because we have not been able to study the properties of the individual particles in solution during the catalytic process," explains the chemist.
Particles on the racetrack
In her ERC project, she is therefore sending several hundred nanoparticles onto the racetrack: they are to circulate in solution in a circle, with their properties and catalytic activity being measured at individual stations. Between the individual measurements, modifications can be made, for example to the size or surface properties of the particles. In this way, Tschulik hopes to draw conclusions as to which characteristics of the particles have a favorable effect on catalytic performance. "If we understand this, we can use this model to produce optimized nanoparticles," she explains.
Press contact
Prof. Dr. Kristina Tschulik
Chair of Analytical Chemistry II
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 29433
e-mail: nanoec@rub.de - 3D Laser Printing in Color
31st August 2020,
Seasoning with Nanosilver.
In the article, the scientists have called it "seasoning" in a winking way and arranged the bowls accordingly: They contain the powder raw material, coated with different nanoparticles for laser-based 3D printing in various colors.
Gökce, CENIDE/UDEVentilation grilles in aircraft cabins, serial components in cars and lately even mascara brushes: The industry has been using laser-based 3D printers for several years now when precision and good mechanical properties are required. However, these printers are expensive, large and print only in white. For home use, desktop devices are becoming available, but they can only print in black – until now. A team from the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) has now brought color into play.
The laser printers for the kitchen table are to become cheaper and smaller – and more colorful: "Instead of the CO2 lasers commonly used in the industry, we are relying on much cheaper diode lasers, such as those with lower output found in CD players," explains Dr. Bilal Gökce from Technical Chemistry I at UDE. "However, you have to be a little tricky." Because the usual polymer powder, the raw material for printing, is white. This means that it reflects all the wavelengths of the visible light – unfortunately including those of diode lasers.
That's when the team had the idea to kill two birds with one stone: The scientists coated the powder grains with nanoparticles made of silver. The point is: In the tiny dimensions of a millionth of a millimeter, materials often have surprising properties. For example, silver appears yellow, while nanogold is red to violet.
Concept Applicable to Other Colors
The previously white polymer was now yellow, and in combination with a diode laser, whose radiation is particularly well absorbed by yellow objects, the idea worked. The result was the first laser-based desktop 3D printing in color – to be read in the current issue of Advanced Optical Materials magazine, which featured the article in its cover.
"Since the nanoparticles sit firmly on the surface of the powder grains and are not just mixed in, even a pinch of them gives a homogeneous color," Gökce says. And what works with silver also works with nanoparticles of other elements. There are no limits to the colors in this process. As a bonus, you also obtain other characteristics of the nanoparticles as well, such as the antibacterial effect of silver or the magnetic properties of iron oxide.
Original Publication:
T. Hupfeld, A. Wegner, M. Blanke, C. Doñate-Buendía, V. Sharov, S. Nieskens, M. Piechotta, M. Giese, S. Barcikowski, B. Gökce
„Plasmonic Seasoning: Giving Color to Desktop Laser 3D Printed Polymers by Highly Dispersed Nanoparticles“
Adv. Optical Mater. 2020, 8, 2000473
https://doi.org/10.1002/adom.202000473Further Information:
PD Dr. Bilal Gökce, Technische Chemie I, +49 201/18 3-3146, bilal.goekce@uni-due.deEditor: Birte Vierjahn, +49 203 37 9-8176, birte.vierjahn@uni-due.de
- International Web Symposium
31st August 2020,
Gas Phase Synthesis of Functional Nanomaterials.
Crystalline iron oxide spheres produced in a flame reactor.
Sascha Apazeller, CENIDE/IVGThe different time zones are taken into account in the order of the presentations: Unlike its three predecessors, this year's "International Symposium on Gas Phase Synthesis of Functional Nanomaterials" from October 6 to 9 will take place online. However, as usual, top-class keynote speakers will be present. More than 100 participants are expected to attend the event organized by the Center for Nanointegration Duisburg-Essen (CENIDE). The registration deadline is September 14, participation is free of charge.
The topics of the English language sessions are "Fundamentals of Particle Formation and Growth", "Modeling and Simulation", "Diagnostics" and "Scale-up and Application". Keynote speakers are Prof. Sotiris Pratsinis (ETH Zurich, Switzerland), Prof. Hai Wang and Prof. Matthias Ihme (both Stanford University, CA, USA). Their presentations will be framed by 20-minute talks, followed by a virtual poster presentation at the end of each session.
The 4th International Symposium is funded by the Priority Program SPP1980 "Nanoparticle Synthesis in Spray Flames SpraySyn: Measurement, Simulation, Processes" and the research group FOR2284 "Model-based Scalable Gas Phase Synthesis of Complex Nanoparticles". Both projects are supported by the German Research Foundation (DFG).
Further information and registration:
https://www.uni-due.de/cenide/symposium_synthesis_2020.php
Prof. Christof Schulz, speaker SPP1980 and FOR2284, Tel. 0203/37 9-8161, christof.schulz@uni-due.de - Prof. Manfred Bayer Takes Office as TU Rector
31st August 2020,
Farewell to Prof. Ursula Gather after Twelve Successful Years .
Prof. Ursula Gather (right) handed over the keys to the office of the Rectorate to the new TU Rector Prof. Manfred Bayer
© Oliver Schaper/TU DortmundChange at the top of TU Dortmund University: Prof. Manfred Bayer takes over the office of Rector of the University on September 1. He succeeds Prof. Ursula Gather, who has led the TU Dortmund University for twelve years over two terms of office. She is retiring after 34 years as a professor at TU Dortmund University.
Prof. Manfred Bayer was elected as the new Rector by an overwhelming majority at the university election meeting on April 24. Before that, the internationally renowned scientist had taught and researched at the Physics Faculty of the TU Dortmund University for 18 years. In addition, he was Chairman of the University Senate from 2008 to 2019.The new rector intends to continue the successful work of his predecessor. One of his goals is to further improve the conditions for students, especially the supervision ratio, i.e. the ratio of students to teaching staff. During Prof. Gather's term of office, the number of students had risen from 22,000 to more than 34,000 - a nationwide trend due to the double A-levels and an increasing willingness to study among the younger generation.
Strengthening international orientation and regional cooperation
Prof. Bayer also wants to further increase the success of the study. To this end, he is considering introducing a "zero" semester. The new rector wants to give the university an even more international orientation, but also expand regional cooperation - for example with the Federal Institute for Occupational Safety and Health, Dortmund University of Applied Sciences and within the UA Ruhr universities. He also wants to further ease the shortage of space at the university. It is also important, he says, to acquire third-party funding from new funding programs in certain areas in order to be able to keep up with the competition in research.
With her re-election in 2015 and a total of twelve years in office, the outgoing Rector Prof. Gather has had a significant impact on the TU Dortmund University: A total of 228 new appointments were made at TU Dortmund during her term of office from September 2008 to the present. She has appointed three of the five professors currently working here. In order to create the best possible conditions for teaching, studies and research, the Rectorate developed a model for a needs-based and performance-oriented distribution of financial resources to the faculties. In addition, the TU Dortmund University has joined the top group of young universities in Germany: Until its 50th birthday in 2018, the university was ranked third nationwide in the QS ranking "Top50 under 50".
Gather was particularly interested in ensuring that the city of Dortmund and the Ruhr area are perceived as a strong science region. For this commitment, she has received several awards, including the title "Citizen of the Ruhr Area" in 2014.
Key officially handed over
"I am very pleased to be able to hand over the office of Rector to such an experienced colleague," she said at the official handover of the keys to the Rectorate office. "I wish you, dear Manfred, a happy hand at all times. Chancellor Albrecht Ehlers joined in the congratulations: "I have already worked very well with Mr. Bayer in his role as Chairman of the Senate. I am very much looking forward to continuing the pleasant and fruitful cooperation with him in this new constellation".
- Programmable Synthetic Materials
28th August 2020,
Materials Research.
Tong Li is an expert for atom probe tomography.
© RUB, MarquardProgrammable synthetic materials
In DNA, information is stored in the sequence of chemical building blocks; in computers, information consists of sequences of zeros and ones. Researchers want to transfer this concept to artificial molecules.
Artificial molecules could one day form the information unit of a new type of computer or be the basis for programmable substances. The information would be encoded in the spatial arrangement of the individual atoms – similar to how the sequence of base pairs determines the information content of DNA, or sequences of zeros and ones form the memory of computers. Researchers at the University of California in Berkeley and Ruhr-Universität Bochum (RUB) have taken a step towards this vision. They showed that atom probe tomography can be used to read a complex spatial arrangement of metal ions in multivariate metal-organic frameworks (MOFs).Professor Tong Li, head of the Atomic-Scale Characterisation research group at the Institute for Materials at RUB, describes the method together with Dr. Zhe Ji and Professor Omar Yaghi from Berkeley in the journal “Science”, published online on 7 August 2020.
Decoding metal sequences
MOFs are crystalline porous networks of multi-metal nodes linked together by organic units to form a well-defined structure. To encode information using a sequence of metals, it is essential to be first able to read the metal arrangement. However, reading the arrangement was extremely challenging. Recently, the interest in characterizing metal sequences is growing because of the extensive information such multivariate structures would be able to offer.
Fundamentally, there was no method to read the metal sequence in MOFs. In the current study, the research team has successfully done so by using atom probe tomography (APT), in which the Bochum-based materials scientist Tong Li is an expert. The researchers chose MOF-74, made by the Yaghi group in 2005, as an object of interest. They designed the MOFs with mixed combinations of cobalt, cadmium, lead, and manganese, and then decrypted their spatial structure using APT.Just as sophisticated as biology
In the future, MOFs could form the basis of programmable chemical molecules: for instance, an MOF could be programmed to introduce an active pharmaceutical ingredient into the body to target infected cells and then break down the active ingredient into harmless substances once it is no longer needed. They could also be used to capture CO2 and, at the same time, convert the CO2 into a useful raw material for the chemical industry.
The synthetic world could reach a whole new level of precision and sophistication that has previously been reserved for biology.
“In the long term, such structures with programmed atomic sequences can completely change our way of thinking about material synthesis,” say the authors. “The synthetic world could reach a whole new level of precision and sophistication that has previously been reserved for biology.”Original publication
Zhe Ji, Tong Li, Omar M. Yaghi: Sequencing of metals in multivariate metal-organic frameworks, in: Science, 2020, DOI: 10.1126/science.aaz4304 - Making Enzymes Fit for Industrial Applications
26th August 2020,
Electrochemistry.
Together with their research partners, the team at the Center for Electrochemistry is working on the development of new catalysts.
RUB, MarquardBacterial enzymes are often powerful but also very sensitive catalysts. To call up their performance, they therefore need a special environment.
Researchers at Ruhr-Universität Bochum (RUB) have developed new techniques for efficiently coupling bacterial enzymes to electrodes. Together with a team from the University of Utah, they realised a system for ammonia synthesis based on a nitrogenase enzyme. They also designed a hydrogen/oxygen biofuel cell based on a hydrogenase enzyme together with a team from the Max Planck Institute for Chemical Energy Conversion. Both papers have been published in the journal “Angewandte Chemie” in May and June 2020.Powerful enzymes require special conditions
Many enzymes that occur in nature are powerful catalysts, such as the so-called [FeFe]-hydrogenases. Hydrogenases are used by bacteria to produce hydrogen, while nitrogenases succeed in activating the strongest bond in nature in nitrogen (N2). Both enzymes are highly sensitive to oxygen, but use readily available non-precious metals in their active centres. Thus they could one day replace expensive precious metal catalysts. “To use such highly sensitive catalysts for biofuel cells is still one of the biggest challenges in sustainable energy conversion,” says Professor Wolfgang Schuhmann, head of the RUB Centre for Electrochemistry and member of the cluster of excellence “Ruhr Explores Solvation”, Resolv.
Biofuel cell realized with enzyme
In cooperation with the team of Professor Wolfgang Lubitz from the Max Planck Institute for Chemical Energy Conversion in Mülheim an der Ruhr, the Bochum group showed under which circumstances this is nevertheless possible. They used a so-called [FeFe] hydrogenase from the bacterium Desulfovibrio desulfuricans. Although this is a very efficient catalyst, it must be protected in the fuel cell from the oxygen required for operation at the second electrode.
In this work, the scientists integrated the [FeFe]-hydrogenase for the first time into a biofuel cell operated with so-called gas diffusion electrodes. In this cell, hydrogen and oxygen are transported to the enzymes through a membrane. The team embedded the enzyme in a matrix consisting of a so-called redox polymer, which fixes the enzyme to the gas-permeable electrode surface, protects the enzyme from the harmful effects of oxygen and also establishes electrical contact between the enzyme and the electrode. With this design, the fuel cell achieved previously unattained high current densities of 14 milliamperes per square centimetre and high power densities of 5.4 milliwatts per square centimetre.
Biobased process for ammonia production
In the second project, the research team at RUB, together with the US group led by Professor Shelley Minteer from the University of Salt-Lake City, looked for a bioelectrosynthetic alternative for ammonia synthesis. In the chemical industry, ammonia is commonly produced using the Haber-Bosch process at high temperature and high pressure and with a considerable release of CO2.
Some bacteria possess enzymes, called nitrogenases, with which they fix molecular nitrogen (N2) and can metabolise it at room temperature and without increased pressure. However, in living organisms this consumes a lot of energy in the form of the energy storage molecules ATP.
The research team showed that it is possible to couple the nitrogenase from the bacterium Azotobacter vinelandii with an electrode through which the necessary electrons for the reaction can be supplied, so that no ATP is required. Once again, the key to success was a redox polymer that helped to establish a stable and efficient electrical contact between the electrode and the nitrogenase/redox polymer composite. “To our knowledge, the fixation and contacting of nitrogenases in redox polymers is the first step in making nitrogenases applicable for bioelectrosynthesis,” write the authors of the study.
Funding
The work with the hydrogenase was financially supported by the German Research Foundation within the framework of the Cluster of Excellence Resolv (EXC 2033, project number 390677874) and within the priority program “Iron-Sulfur for Life” (SPP 1927, project BI 2198/1-1). Further support came from the Max Planck Society.
The work with the nitrogenase was supported by the US Department of Energy (DE-SC0017845), by Fulcrum Biosciences, by the German Research Foundation within the Cluster of Excellence Resolv (EXC 2033, project number 390677874), by the European Research Council and within the framework of the European Union’s Horizon 2020 research and innovation programme (CasCat, funding number 833408).
Original publications
Julian Szczesny, James A. Birrell, Felipe Conzuelo, Wolfgang Lubitz, Adrian Ruff, Wolfgang Schuhmann: Redox‐polymer‐based high‐current‐density gas‐diffusion H2‐oxidation bioanode using [FeFe] hydrogenase from Desulfovibrio desulfuricans in a membrane‐free biofuel cell, in: Angewandte Chemie International Edition, 2020, DOI: 10.1002/anie.202006824Yoo Seok Lee, Adrian Ruff, Rong Cai, Koun Lim, Wolfgang Schuhmann, Shelley D. Minteer: Electroenzymatic nitrogen fixation using a MoFe protein system immobilized in an organic redox polymer, in: Angewandte Chemie International Edition, 2020, DOI: 10.1002/anie.202007198
Press contact
Prof. Dr. Wolfgang Schuhmann
Analytical Chemistry
Center for Electrochemistry
Faculty of Chemistry and Biochemistry
Ruhr-Universität Bochum
Germany
Phone: +49 234 32 26200
Email: wolfgang.schuhmann@rub.de - Chemists in the Heisenberg Program
25th August 2020,
High Distinction for two Materials Chain Scientists.
© V. Unkovic, © B. GökceDeveloping new materials: Junior Professor Michael Giese does this just like Lecturer Dr. Bilal Gökce - but in very different ways. For their outstanding research, the two chemists from the Materials Chain at University of Duisburg-Essen (UDE) have been accepted into the Heisenberg Program of the German Research Foundation (DFG).
Funding is being provided for Giese's project "Supramolecular liquid crystals - a modular concept for 'smarter' materials", in which he and his team are designing a sort of construction kit. Its components can be assembled to form substances with desired properties.
Liquid crystals are the focus of his research. "We encounter them in everyday life, for example in cell phones or flat screens," explains Giese. "In our module system, we can add structural color components to the liquid crystals. In nature, this color makes bird feathers or insect wings shimmer and is created by the refraction of light.
The exciting thing, says Giese: Depending on the composition of the materials, they react to various changes in the environment. For example, if temperature or light changes, they can modify their properties again and again.
"In the laboratory, we first let nature run wild, it is the master builder, and the molecular building blocks and patterns create themselves autonomously," explains Michael Giese. "The challenge for us is to design the components afterwards so that they can be used in a versatile and flexible way.
Better Materials for 3D Printing
Gökce, on the other hand, focuses on 3D printing. "The enormous potential of powder-based 3D printing has not yet been fully realized because many available materials are still inadequate for these printers. I'm enabling 3D printing of new materials through the targeted addition of nanoparticles and improving the properties of 3D-printed polymer or metal components," the chemist explains.
Bilal Gökce is pursuing two directions. First, he is investigating how laser-based nanoparticle production can be upscaled and the size of the particles produced can be controlled. He uses these nanoparticles to develop new powders for 3D printing of magnets, optics or materials with special mechanical properties. "For the first time, the entire process chain of 3D printing - from material to component - will be explored in a holistic approach," says the UDE scientist.
Gökce himself receives much praise from the DFG reviewers: In his proposal, the DFG states that "the goals and sub-goals are so perfectly described and completely convincingly substantiated that one can be sure that real progress in understanding materials and developing methods will be achieved here."
The Heisenberg Program honors highly qualified researchers in all disciplines and is intended to enable them to work on more advanced topics, among other things. Of the four funding options in the program, the professorship is the most desired.
Further information:
Jun. prof. Dr. Michael R. A. Giese, Organic Chemistry, Supramolecular Materials, Tel. 0201/18-3 2087, michael.giese@uni-due.de
PD Dr. Bilal Gökce, Technical Chemistry I, Tel. 0201/18-3 3146, bilal.goekce@uni-due.deEditorial Office: Alexandra Nießen, Tel. 0203/37 9-1487, alexandra.niessen@uni-due.de
- Priority Program Continues
24th August 2020,
From Detailed Understanding to Industrial Scale.
View of the center of the standardized synthesis reactor "SpraySyn", which was specially developed for the reproducible production and investigation of nanoparticles from a spray flame. The flame is examined using a special sampling probe that is suitable for temperatures of up to 2600°C.
© Samer Suleiman, IVG/CENIDEMany materials reveal new, promising properties when they are nanostructured, i.e. built up from tiny particles. One way of doing this is spray flame synthesis, which can be used to produce a wide variety of materials. Making the process already established in the laboratory ready for industrial scale is one of the aims of the Priority Program (SPP) 1980 under the coordination of the Center for Nanointegration (CENIDE) at University of Duisburg-Essen (UDE). The German Research Foundation is funding the program for another three years with about 7.5 million euros.
Since 2017 the project partners have been working under the coordination of UDE Professor Christof Schulz to understand the underlying processes of spray flame synthesis. With this knowledge, alternatives for expensive specialty chemicals and solvents can be found and the required synthesis plants can be designed to fit exactly. Only then the process is attractive for larger scale industrial applications and the production of materials, for example for batteries, catalysts or gas sensors.
Building on acquired knowledge
"Now, in the second funding phase, we are focusing on further questions: How can the processes be transferred to industrial scale? What can be used to replace expensive or toxic raw materials and which product spectrum is possible at all," explains Schulz. To this end, the scientists continue to use the specially developed standard burner "SpraySyn", whose standardized structure is used to study the spray flame synthesis of nanoparticles in detail. The results can be used to develop simulation procedures that help transfer the process from laboratory to production scale. A database not only documents the results of all project participants, but also serves beyond the SPP to document and further develop the process understanding.
The UDE is significantly involved in eight of the 19 projects of the SPP 1980 "Nanoparticle synthesis in spray flames, SpraySyn: measurement, simulation, processes". Its nanoparticle synthesis facility at the NanoEnergieTechnikZentrum (NETZ) closes the gap between laboratory scale and industrial production. In addition, all project partners have access to a joint central laboratory for laser-optical investigations in the NETZ.
Further information:
https://www.uni-due.de/spp1980
Prof. Christof Schulz, Institute of Combustion and Gas Dynamics - Reactive Fluids, Tel. 0203/37 9-8161, christof.schulz@uni-due.de - Challenges in the Development of Electrocatalysts
20th August 2020,
Energy Conversion.
© RUB, MarquardEfficient catalysts are crucial for energy conversion. However, findings from basic research rarely make it into practice at present. What would have to change to develop efficient, stable and selective catalysts for industrial application is described by Prof. Dr. Corina Andronescu from the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) and partners from the Max Planck Institute for Chemical Energy Conversion and Ruhr-Universität Bochum in a review article. It was published online in the journal “Angewandte Chemie” on 30 June 2020.
Three chemical reactions would be particularly suitable for energy conversion: the electrolysis of water to hydrogen and oxygen, which can later be used to generate electrical energy in fuel cells; the conversion of nitrogen into ammonia, an important starting material for the chemical industry; and the electrochemical conversion of CO2 into other starting materials for industry, such as ethylene.
Activity, selectivity and stability of catalysts
In their review article, the authors from the University Alliance Ruhr (UA Ruhr), describe that research on new catalysts must always keep three factors in mind: activity, selectivity and stability. Activity describes how powerful a catalyst is at a given energy input. Selectivity is defined as the ability to produce the desired substance without contaminating by-products. The stability indicates how efficient a catalyst is in the long run.
“Many publications claim high activity, stability and selectivity of electrocatalysts for important energy conversion reactions, but there is a lack of evidence”, says Wolfgang Schuhmann, head of the Centre for Electrochemistry and member of the Ruhr Explores Solvation Cluster of Excellence, Resolv (solvation.de).
Gap between basic research and application
Masa, Andronescu and Schuhmann criticize, among other things, that often not enough importance is attached to the stability of catalysts. “The underestimation of catalyst stability is largely responsible for the huge gap between seemingly exciting breakthroughs in the design of active catalysts and the practical implementation of such catalysts in technical applications,” they write.
The team identifies five factors that hinder the step from research to practice:
- - The performance and material properties of catalysts under application-relevant conditions differ from those under laboratory conditions.
There are no defined guidelines for assessing and comparing the performance of catalysts. - - Unsuitable characterisation methods are often used to determine the performance of electrocatalytic reactions.
- - Too little is known about the active centres of the catalysts and their long-term stability. For example, influences of the surrounding solvent molecules and ions on the function are neglected.
- - To determine the activity of a catalyst, its actual surface area must be known. Nanoparticle ensembles are often used as catalysts for which conventional methods of surface determination are not suitable
In their article, Justus Masa, Corina Andronescu and Wolfgang Schuhmann use experimental results to demonstrate how important it is to always think about the stability of catalysts in an integrated way with their activity.
Original Publication: Justus Masa, Corina Andronescu, Wolfgang Schuhmann: Electrocatalysis as the nexus for sustainable renewable energy. The Gordian knot of activity, stability, and selectivity, Angewandte Chemie International Edition, 2020, DOI: 10.1002/anie.202007672
https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202007672?af=RFurther Information:
Prof. Dr. Corina Andronescu, Technical Chemistry III (University of Duisburg-Essen), corina.andronescu@uni-due.de
Prof. Dr. Wolfgang Schuhmann, Analytische Chemie (Ruhr-Universität Bochum), Tel. 0234/32 2620, wolfgang.schuhmann@rub.deEditor: Dr. Julia Weiler (RUB)
- - The performance and material properties of catalysts under application-relevant conditions differ from those under laboratory conditions.
- Laser Expert Receives DAAD Scholarship
20th August 2020,
Research in Moscow.
© privatThere are projects that cannot be realized in video chat. Dr. Peter Fyodorov, laser physicist at University of Duisburg-Essen (UDE), will be spending a year in Moscow starting in September doing research with an internationally renowned expert. The German Academic Exchange Service (DAAD) finances his position through the PRIME program*.
"Just two weeks ago I got the green light for the trip, Russia is still a high-risk area," says Peter Fyodorov, who works at the engineering science institute for combustion and gas dynamics. Because of Corona, he is therefore probably one of the few PRIME candidates this year who can start their project.
In Moscow, the 37-year-old has chosen the working group around Professor Vladimir Kozlovsky at the Lebedev Institute of the Russian Academy of Sciences. The host is recognized worldwide for the growth of laser crystals, which are used, among other things, to develop various lasers in the mid-infrared range (MIR). They enable very sensitive measurements of gas phase species in physico-chemical processes, for example.
Fyodorov will combine the MIR lasers with the ICAS (intracavity absorption spectroscopy) measuring technique. "This technology is my specialty," says the UDE scientist. With ICAS, the sample to be examined is placed directly into the laser, which enables high measurement sensitivities. "If we combine the know-how of the Russian institute and the UDE, we can achieve extremely high sensitivity and thus discover so-called intermediates in combustion processes. These substances, which are created in the course of a multi-stage chemical process, often play an important role. However, since they occur in very low concentrations, they have only been studied to a limited extent," says Fyodorov.
Another PRIME fellow from the UDE has just returned from his stay abroad: Dr. Leonid Ryvkin. He spent a year at the Institut de Mathématiques de Jussieu-Paris Rive Gauche, the largest research center for basic mathematics in France. There Ryvkin worked on so-called multisymplectic geometry and singular foliations.
* PRIME is the abbreviation for Postdoctoral Researchers International Mobility Experience.
Further information:
Dr. Peter Fyodorov, Institute of Combustion and Gas Dynamics, Tel. 0203/37 9-4772, peter.fjodorow@uni-due.deEditorial office: Alexandra Nießen, Tel. 0203/37 9-1487, alexandra.niessen@uni-due.de
- Christof Schulz New Deputy Director
18th August 2020,
Decision of the Management Board.
© IVGProfessor Christof Schulz (Faculty of Engineering - University of Duisburg-Essen) is the new Deputy Scientific Director of CENIDE - the Board of Directors elected him at its meeting last Thursday.
He succeeds Professor Malte Behrens (Faculty of Chemistry), who has held the office since December 2018 but was not up for re-election due to his call to Kiel. Scientific director is still Professor Heiko Wende (Faculty of Physics).
Further information:
Dr. Tobias Teckentrup, phone 0203 37 9-8178, tobias.teckentrup@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Research Report Nanosciences
7th August 2020,
Successful performance.
© AG Bovensiepen/N. Rothenbach et al., Phys. Rev. B 100 (2019)Tiny polymer cups that could one day remove oil residues from water or the production of high-quality catalyst materials in just one step - exciting scientific insights are offered by the new special issue "Nanosciences", which was published on the occasion of the research report of University of Duisburg-Essen (UDE).
In 2018 and 2019, two new Collaborative Research Centers (SFB/TRR 247 "Heterogeneous Oxidation Catalysis in the Liquid Phase" and SFB/TRR 270 "HoMMage - Hysteresis Design of Magnetic Materials for Efficient Energy Conversion" have been launched or approved. Together with the SFB 1242 "Non-equilibrium dynamics of condensed matter in the time domain", which has been in existence since 2016, CENIDE an Materials Chain members now play a major role in three SFB/TRRs and are involved in another one with six subprojects.
In addition to these and other highlights on publications, international cooperations, prizes and awards, the topics of transfer and sustainability are not neglected, because: The development and research of sustainable technologies and materials is the focus of many Cenide and Materials Chain working groups.
The Nanoscience Research Report can be downloaded from www.uni-due.de/imperia/md/content/cenide/forschungsbericht2019.pdf. Printed copies are available on request.
Editor: Steffi Nickol, 0203 37-98177, steffi.nickol@uni-due.de
Sarah Heuser, sarah.heuser@uni-due.de - New High-tech Microscope in Physics
4th August 2020,
Zoom in to Half a μ.
Prof. Marika Schleberger changing samples.
© UDE/Andreas ReichertFunny question: What do physicists do all day long? They measure! The research group of Materials Chain and CENIDE member Prof. Marika Schleberger from University of Duisburg-Essen (UDE) has now acquired a special device with which it can characterize 2D materials even better than before. This so-called confocal Raman microscope provides high-resolution images combining information from Raman, photoluminescence spectroscopy and scanning probe microscopy. In this way, the structure and electronic properties of graphene and other wonder materials can be precisely determined.
The samples that come under the new microscope are only a few tens of micrometers in size. They do not have to be marked or prepared in any other way. You can zoom in, scan the area and measure structures that are only half a micrometre in size - at thousands of positions on the sample.
"The instrument will greatly accelerate the demanding analyses of our working group. For a measurement with 250 x 250 points we will only need about 15 minutes, which otherwise took three hours," says experimental physicist Schleberger happily. "Thanks to the excellent resolution and the combination of the methods, the different spectra can be recorded in parallel for each point and displayed in color-coded form."
In future, the device will not only be used by researchers. Advanced students of physics, energy science and nanoengineering will also learn how to use the special microscope and become familiar with 2D materials. "As ultra-thin, quasi two-dimensional layers, these materials have completely different properties than in their usual three-dimensional form," explains Schleberger. "Ultra-thin molybdenum disulfide, for example, glows when irradiated with a laser. It can therefore be used for flexible LEDs."
How much does a confocal Raman microscope like this cost? At 470,000 euros, it is nothing "that can be paid out of petty cash", says Schleberger. "Fortunately, the German Research Foundation and the state of North Rhine-Westphalia supported the purchase."
Further information:
https://www.uni-due.de/physik/newsarchiv2020.php
Prof. Dr. Marika Schleberger, Experimental Physics, Tel. 0203/37 9-1600, marika.schleberger@uni-due.deEditor: Ulrike Bohnsack, Tel. 0203/37 9-2429, ulrike.bohnsack@uni-due.de
- Nanocatalysts Made of Metallic Glass
20th July 2020,
Humboldt Fellow at NETZ.
© privatThey combine the properties of metal and glass and thus reveal new possibilities: Among other features, metallic glasses have extraordinary catalytic properties. Dr. Shunxing Liang intends to exploit this for water splitting, i.e. the production of hydrogen as an energy carrier. To this end, he wants to generate nanoparticles of this promising material by pulse laser ablation in liquids. The 29-year-old is a Humboldt Fellow at the NanoEnergieTechnik-Zentrum (NETZ) at the University of Duisburg-Essen (UDE) for one year.
Metallic glasses are comparatively new in the glassy family. They combine the best of both materials. They conduct electricity like metals but have an internal structure like glass that is completely untypical of alloys: Their atoms are not arranged in a regular lattice but are as mixed up as in our windows made of classic silicate glass. This chaotic structure makes the material e.g. stronger than traditional alloys (like steel and bronze), and thus provides a wider application potential.
New Generation of Nanocatalysts
“Because of their large surface compared to their volume, nanoparticles are, in general, very well suited for catalytic purposes”, explains Dr. Shunxing Liang. “Let alone those made of metallic glasses.” His method of choice to synthesize these new generation of nanocatalysts is laser ablation in liquids. In this process, a laser vaporizes material from the selected substrate with ultra-short laser pulses. In the surrounding solvent, the material combines to form nanoparticles.
What sounds simple has never been achieved with the envisaged material: Dr. Liang aims to stabilize the disordered structure in the particles during their synthesis. "It is an ambitious but promising plan", says Dr. Sven Reichenberger, head of the junior research group on laser-based synthesis of nanomaterials for energy research, where the Alexander von Humboldt fellow takes part in. "Within a few billionths of a second, we locally heat the materials to temperatures like those prevailing on the sun’s surface and then cool the ejected material back down to the ambient temperature just as quickly. This leaves the atoms no time to rearrange in a regular lattice."
Dr. Reichenberger’s laboratories are located in the NETZ, a research building dedicated to the development of materials for energy technology. The microscopy center in the basement makes it possible to analyze samples on the spot and thus improve the production process step by step.
Dr. Liang studied mechanical engineering at South China Agricultural University before completing his master and PhD degree at Edith Cowan University in Perth, Australia. Back then, he mainly focused on metallic glasses and their advanced application in wastewater treatment.
Further Information:
Dr. Shunxing Liang, Technical Chemistry I, + 49 203/37 9-8217, shunxing.liang@uni-due.de
Dr. Sven Reichenberger, Technical Chemistry I, +49 203/37 9-8116, sven.reichenberger@uni-due.de
https://www.uni-due.de/reichenberger-group/Editor: Birte Vierjahn, Tel. +49 203/37 9-8176, birte.vierjahn@uni-due.de
- Superconducting Nickelates
17th July 2020,
Cuprate-like Behavior in a Nickel-oxide Film.
Side view of the infinite-layer (top) and the perovskite structure (bottom) on SrTiO3. Only the infinite layer structure induces a two-dimensional electron gas at the interface (framed in blue).
© B. Geisler and R. PentchevaSuperconductors transmit electric current without loss at any distance and play an important role in quantum computers and medical imaging. Unfortunately, the stars among the electrical conductors work exclusively at extremely low temperatures. Since the discovery of high-temperature superconducting cuprates with their characteristic copper-oxygen plaquettes in 1986, scientists have been searching for similar behavior in other materials classes. It was not until 2019 that superconductivity was reported in a nickel oxide, but the underlying mechanism is still unclear. Theoretical physicists from the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) have therefore studied the electronic properties of the material and found a possible explanation.
Since bulk neodymium nickel oxide (NdNiO2), which exhibits an analogous crystal structure and valence electron number as the cuprates, does not show superconductivity, Prof. Rossitza Pentcheva and Dr. Benjamin Geisler focused on the role of the film geometry. They simulated a 1.5 nanometer thin layer of this so-called infinite-layer nickelate on a strontium titanate substrate (SrTiO3) in comparison to a perovskite (NdNiO3) film based on quantum-mechanical simulations at the supercomputer MagnitUDE.
Two-dimensional electron gas discovered
Despite the fact that both systems have a charge mismatch at the interface, a major difference appears in accommodating it: Only in the infinite-layer case does the charge mismatch lead to the formation of a two-dimensional electron gas at the interface. "It is known from other materials combinations that such a two-dimensional electron gas can be superconducting" explains Pentcheva. Moreover, in contrast to the bulk, the infinite-layer film shows a cuprate-like electronic behavior, indicating that the film geometry may play a significant role in the emergence of superconductivity.
The more that is known about the origin of superconductivity, the better the chances are that the sought-after property can be specifically induced in tailor-made material systems, even at room temperature.
Original Publication:
B. Geisler and R. Pentcheva: „Fundamental difference in the electronic reconstruction of infinite-layer versus perovskite neodymium nickelate films on SrTiO3(001)“. Phys. Rev. B 102, 020502(R) (2020) , Rapid Communication, Editors’ Suggestion
https://doi.org/10.1103/PhysRevB.102.020502Further Information:
Prof. Rossitza Pentcheva, Computational Materials Physics, +49 203 37 9-2238, rossitza.pentcheva@uni-due.deEditor: Birte Vierjahn, +49 203 37 9-8176, birte.vierjahn@uni-due.de
- Science and Society in Dialogue
14th July 2020,
Engineer Appointed to the Young Academy of the Leopoldina.
© UDE/Frank PreußAnyone who is a member here has not only written an excellent dissertation, but has also done outstanding work beyond that - and has done so at a young age: Junior Professor Doris Segets from the Center for Nanointegration (CENIDE) at University of Duisburg-Essen (UDE) has been appointed to the Young Academy of the Leopoldina. Together with 49 other scientists and artists, she now has the opportunity for five years to help shape the exchange between society and research.
"My selection interview was on a Friday afternoon, and then it all happened one after the other," reports Segets. "The decision came that very evening and six days later the first meeting began - partly online, partly in presence in Berlin. Our topics ranged from mopheads to artificial intelligence and EU science policy. It was incredibly inspiring, but I was also quite exhausted afterwards".
Since December 2018, Segets has headed the working group "Process Technology for Electrochemical Functional Materials" at the NanoEnergyTechnologyCenter (NETZ) at UDE. Her professorship is part of the programme for the promotion of young scientists (WISNA) set up by the federal government, which aims to offer young scientists a transparent and plannable path to a lifetime professorship.
Her focus is on the further processing of functional nanoparticles for future technologies such as batteries or fuel cells: Among other things, her research group analyses the properties of these particles in order to understand how they behave in contact with certain liquids. If they can be distributed in a controlled manner, the result is a dispersion such as an ink or paste from which structured, functional layers can be printed over large areas for numerous applications.
From science to society
The Young Academy is a joint project of the Berlin-Brandenburg Academy of Sciences and Humanities and the renowned Leopoldina. It offers young scientists and artists a platform for exchange among themselves across disciplines, but also for dialogue between science and society. With personal and central research budgets, members can jointly organize scientific projects such as workshops, panel discussions or symposia.
Further information:
Junior Professor Doris Segets, Process Engineering for Electrochemical Functional Materials, Tel. 0203/37 9-8230, doris.segets@uni-due.de - Position Paper from the Engineering Sciences
8th July 2020,
.
A technology-open approach on the way to a global climate-neutral energy system - this is what more than 50 professors from leading German universities and research institutions recommend, including Prof. Christof Schulz from the Center for Nanointegration (CENIDE) at University of Duisburg-Essen (UDE). A position paper drawn up jointly with engineering scientists from Darmstadt Technical University and RWTH Aachen University draws attention to the thermal use of chemical energy sources. In addition to electrochemical energy conversion, these are indispensable for safe power generation and energy supply in vehicles, industry and residential buildings.
"In the current climate target discussion, it is important to develop various technical options, which are indispensable for our society from an ecological and economic point of view, in parallel", the authors of the position paper are certain.
Under the chairmanship of TU Darmstadt, around 50 internationally renowned scientists conducting research on chemically reactive flows and energy process engineering are calling for a strong competition of ideas. "In research and development, we would like to see guard rails from politicians, but not predetermined technology paths." The authors welcome the EU funding programme for hydrogen technology presented by the EU Commission as well as the German government's National Hydrogen Strategy. With their position paper, they also want to point out options with which the engineering and natural sciences can responsibly master the challenges posed by the restructuring of our energy systems. They point to the extensive expertise on thermochemical energy technologies available in Germany.
Replacing fossil energy sources
The position paper outlines a gradual transformation of the energy system towards climate neutrality with the help of chemical energy sources. Processes for the thermochemical and electrochemical energy conversion of fuels, such as those used in gas-fired power plants and fuel cells, are to be further developed.
Gas turbines in the electricity industry or hybrid drives in vehicles would continue to be useful and necessary in order to achieve the goals of reducing global warming. Fossil energy sources used so far, however, would have to be increasingly replaced by regeneratively produced, for example CO2-neutral synthetic hydrocarbons. The proportion of carbon-free chemical energy carriers such as hydrogen produced with renewable energy is to increase.
"Responsibility for a resilient energy system"
The authors emphasize that an energy system geared purely to electric drives and storage systems cannot reliably cover demand. Important sustainable energy sources such as wind power and photovoltaics are subject to production fluctuations. There is a lack of capacity to store electrical energy on a large scale. The use of chemical energy sources from regenerative sources to generate electricity in power plants is a necessary component of the energy system after the phase-out of nuclear power and coal. Synthetic fuels can also make a contribution to energy system transformation in air and sea transport.
In the opinion of the scientists, research and development, for example on energy converters for operation with non-fossil fuels and on plants with high efficiencies and low pollutant emissions, should be promoted, especially in Germany.
Further information:
Position Paper
Prof. Christof Schulz, Institute of Combustion and Gas Dynamics - Reactive Fluids, Tel. 0203 37 9-8161, christof.schulz@uni-due.de - New Chemistry for Ultra-thin Gas Sensors
1st July 2020,
Material Research.
Lukas Mai – he is reflected in a thin film – and Anjana Devi.
© RUB MarquardThe application of zinc oxide layers in industry is manifold and ranges from the protection of degradable goods to the detection of toxic nitrogen oxide gas. Such layers can be deposited by atomic layer deposition (ALD) which employs typically chemical compounds, or simply precursors, which ignite immediately upon contact with air, i.e. are highly pyrophoric. An interdisciplinary research team at Ruhr-Universität Bochum (RUB) has now established a new fabrication process based on a non-pyrophoric zinc precursor that can be processed at temperatures low enough to allow plastics to be coated. The team published their report in the journal “Small”, where it was featured as the cover story in the edition from 4 June 2020.
Deposition ultra-thin layers
In order to produce a sensor for nitrogen dioxide (NO2), a thin layer of nanostructured zinc oxide (ZnO) must be applied to a sensor substrate and then integrated into an electrical component. Professor Anjana Devi’s team used ALD to apply ultra-thin ZnO layers on such sensor substrates.
In general, ALD processes are used in industry to miniaturise electrical components using ultra-thin layers, some of which are only a few atomic layers thick, while at the same time increasing their efficiency. For that, suitable precursors are required that react at surfaces to form such a thin film. “The chemistry behind ALD processes is therefore essential and has a huge impact on the resulting thin films,” points out Anjana Devi.
Safe handling and highest quality
To date, industrial manufacturers have been producing ZnO thin films by deploying an extremely reactive, highly pyrophoric zinc precursor via ALD. “The key for the development of a safe alternative ALD process for ZnO at RUB was to develop a new, non-pyrophoric precursor that is safe to handle and is able to deposit ZnO thin films of the highest quality,” explains Lukas Mai, lead author of the study. “The challenge was to find alternative chemistries to replace the pyrophoric compounds that are generally used in the industry for ZnO.”
The unique aspect of the new process is that it can be performed at very low process temperatures, thus facilitating deposition onto plastics. Consequently, the new process can be used not only for the manufacture of gas sensors, but also of gas barrier layers. In the packaging industry, such layers are applied on plastics to protect degradable goods such as food or pharmaceuticals from air.
Cooperation partnersThe research could be carried out thanks to an interdisciplinary collaboration of natural scientists and engineers. The team included the research groups Inorganic Materials Chemistry headed by Professor Anjana Devi and Electrical Engineering and Plasma Technology headed by Professor Peter Awakowicz, researchers from Heinrich-Heine-Universität Düsseldorf, and the company Paragon.
FundingThe research was funded by European Regional Development Fund (EFRE) in the Funald project and by the German Research Foundation as part of the Collaborative Research Centre/Transregio TR87. Lukas Mai was funded by Stiftung der Deutschen Wirtschaft for his doctoral studies.
Original publicationLukas Mai et al.: Zinc oxide: from precursor chemistry to gas sensors: plasma‐enhanced atomic layer deposition process engineering for zinc oxide layers from a nonpyrophoric zinc precursor for gas barrier and sensor applications, in: Small, 2020, DOI: 10.1002/smll.202070122
Editor: Meike DrießenPress contactProf. Dr. Anjana Devi
Inorganic Materials Chemistry
Chair of Inorganic Chemistry II
Faculty of Chemistry and Biochemistry
Ruhr-Universität Bochum
Germany
Phone: +49 234 32 24167
Email: anjana.devi@rub.de - Nanoparticles at the Push of a Button
29th June 2020,
EU Project Starts.
The future founders Tobias Bessel (left) and Dr. Friedrich Waag do not need the laser safety glasses to operate their invention.
© privatInsert capsule, refill with water if necessary, switch on: The machine whirrs a little, and the precious item runs into the waiting vessel. This is not about coffee, but nano particles. Two scientists from the Center for Nanointegration (CENIDE) at University of Duisburg-Essen (UDE) will start the "AutoProNano" project in July, in which their particle production machine, for which a patent has already been applied for, will be made ready for the market. Their goal is to spin off the company at the beginning of 2022.
Colloidal nanoparticles are tiny particles of only a few millionths of a millimetre in diameter that float as separately as possible in a liquid. They are usually very expensive: gold nanoparticles cost about 300 times more than the same amount of pure precious metal in one piece.
The prospective founders want to make life easier for researchers and developers: Their machine delivers colloidal nanoparticles at the touch of a button, whenever you need them. "It can be operated without instruction and only requires a power socket," explains chemist Dr. Friedrich Waag, who is managing the project together with Tobias Bessel, a chemical engineering assistant. In addition, production is very cost-effective and other costs are eliminated. But there is another reason why Bessel sees great potential for their development: "I can't think of any industry in which nanoparticles are not used as a general rule".
Uncomplicated material change
And this is how the compact benchtop unit works: Three tanks contain different solvents; the desired particle raw material is inserted into the machine as a platelet in a capsule. At the push of a button, the integrated microchip laser vaporizes material from the platelet surface with ultra-short pulses. In order to generate colloids of different material combinations, the liquid and platelets can be easily exchanged. The automatic cleaning in between prevents contamination.
Waag and Bessel are currently looking for reinforcements for their team. "And we would be pleased if interested pilot users from research and development contact us," says Waag.
The project is funded by the Europäischen Fonds für regionale Entwicklung, EFRE for short. The UDE supports the future founders primarily with offices and laboratories that they are allowed to use in Technical Chemistry I. This is also where Waag and Bessel got to know each other during their doctorates and training.
Photo: They do not need the laser safety glasses to operate their invention: The future founders Tobias Bessel (left) and Dr. Friedrich Waag.
Further information:
Dr. Friedrich Waag, Technical Chemistry I, Tel. 0201 / 18 3-3750, friedrich.waag@uni-due.de - DLR_School_Lab is Online
26th June 2020,
Prof. Metin Tolan Enriches School Lab with One-hour Film.
© Martina Hengesbach/TU DortmundThe DLR_School_Lab at the TU Dortmund University goes online. At the end of June, Prof. Metin Tolan from the Faculty of Physics enriched the offer of the School Lab with an approximately one-hour film about the infinite vastness of the universe. Tolan's contribution will be included in the nationwide offering of the 13 DLR_School_Labs.
Prof. Tolan's mouthguard bears the Star Trek symbol when he comes to the DLR_School_Lab in Dortmund. "Unusual times", he says in view of the depopulated campus and the almost empty laboratory. Only a four-member recording team - all of them trainees in the field of media design, image and sound at the TU Dortmund University's nrwrision learning channel - as well as School_Lab director Dr Sylvia Rückheim and three visitors await him there. In front of this unusually small audience, Tolan, but then without a mask, leads into the universe and to the two themes: Rocket propulsion and planets in distant star systems.
DLR_School_Labs switched to digital formats
Media professional Tolan, who is also the winner of the Communicator Prize of the German Research Foundation, prepares his topics in his usual professional manner. The film crew Quentin Federau, Zoran Garic, Robin Leyendecker and Florian Polenz accompany his presentation with several cameras. After shooting, they also take care of editing the material and the final version of the film. Meanwhile, Tolan reports on the frustration of space travel, namely that an enormous amount of energy is needed to shoot material into space. About 25 years ago, Tolan continues, a first planet outside our solar system was discovered there. Would there be other intelligent life out there? Life probably does, but intelligent? Mother Earth has also left her fingerprint in the universe by broadcasting television programs. Whether this is considered a civilizing achievement by extraterrestrials who receive these radio waves? Tolan dithers. He releases his soon to be many viewers on the net and the three guests in the School_Lab with the Vulcan greeting "Live long and prosper". Applause from the few spectators.
The Covid 19 pandemic had also led to the closure of the Dortmund School_Lab in March 2020. In normal times, Sylvia Rückheim familiarises around 120 classes with several thousand pupils every year with phenomena from aerospace technology, but also from physics in general. Because of the corona pandemic, the DLR_School_Labs have switched to digital formats, from apps for virtual flying, to teaching materials for downloading, handicraft templates and hands-on experiments, to film clips. These professionally produced films - there are currently two - can be viewed on DLR's YouTube channel.
- New Insights into the Energy Levels in Quantum Dots
25th June 2020,
Physics.
Schematic representation of a charged exciton, i.e. an excited state consisting of two electrons and a hole in a quantum dot
© RUB, Arne LudwigResearchers have experimentally proven the theoretically predicted Auger effect in quantum dots. The findings help to understand the structures that could form the basis of quantum communication.
Researchers from Basel, Bochum and Copenhagen have gained new insights into the energy states of quantum dots. These semiconductor nanostructures are promising candidates for the basic information units for quantum communication. With their experiments, the scientists confirmed certain energy transitions in quantum dots that had previously only been predicted theoretically: the so-called radiative Auger process. For the investigations, the researchers in Basel and Copenhagen used special samples produced by the team from the Chair of Applied Solid State Physics at Ruhr Universität Bochum (RUB). They report on the results in the journal Nature Nanotechnology, published online on 15 June 2020.Locking up charge carriers
In order to create a quantum dot, the Bochum researchers use self-organizing processes in crystal growth. In the process, they produce billions of nanometre-sized crystals from, for example, indium arsenide. In these they can trap charge carriers, such as a single electron. This construct is interesting for quantum communication because information can be encoded with the help of charge carrier spinning. For this coding it is necessary to be able to manipulate and read the spin from the outside. During readout, quantum information can be imprinted into the polarisation of a photon, for example. The photon then carries the information at the speed of light and can be used for quantum information transfer.
This is why scientists are interested, for example, in what exactly happens in the quantum dot when energy is irradiated from outside onto the artificial atom.
Special energy transitions demonstrated
Atoms consist of a positively charged nucleus surrounded by one or more negatively charged electrons. If an electron in an atom is excited, i.e. has an increased energy, it can reduce this energy in two ways: It can release the energy in the form of a single particle of light (photon) without affecting the other electrons. Or it comes to the Auger process, in which the high-energy electron transfers all its energy to the other electrons in the atom. This effect was discovered in 1922 by Lise Meitner and Pierre Victor Auger. About a decade later, physicist Felix Bloch described the so-called radiative Auger process. In this process the excited electron splits its energy between another electron in the atom and a photon.
A semiconductor quantum dot resembles an atom in many ways. However, the radiative Auger process had previously only been predicted theoretically for quantum dots. Experimental proof has now been provided by researchers from Basel. The physicists Dr. Matthias Löbl and Prof. Dr. Richard Warburton, together with colleagues from Bochum and Copenhagen, demonstrated the radiative Auger process in the smallest possible system of one electron and one photon. This was the first time they showed a connection between this process and quantum optics. They proved that quantum optical measurements with the radiating Auger process can be useful to study the dynamics of single electrons.
Applications for quantum dots
Using the radiant Auger effect, scientists can also precisely determine the structure of the quantum mechanical energy levels available to a single electron in the quantum dot. Until now, this has only been possible indirectly through calculations in combination with optical methods. Now a direct proof has been achieved. This helps to better understand the quantum mechanical system.
In order to find ideal quantum dots for different applications, questions such as How much time does an electron remain in the energetically excited state? What energy levels does a quantum dot form? And how can this be influenced by manufacturing processes?
Different quantum dots in stable environments
The group observed the effect not only in quantum dots in indium arsenide semiconductors. The Bochum team Dr. Julian Ritzmann, Dr. Arne Ludwig and Prof. Dr. Andreas Wieck also succeeded in producing a quantum dot from the semiconductor gallium arsenide. With both materials, the scientists were able to create quantum dots with very stable environments, which was crucial for demonstrating the radiative Auger process. For many years, the group at the Ruhr-Universität Bochum has been working on the optimal conditions for stable quantum dots.
Funding
The project was funded by the National Centre of Competence in Research "Quantum Science and Technology", the Swiss National Science Foundation (Grant No. 200020 156637), the European Union within the Horizon 2020 Programme (Grant Nos. 721394 and 840453), the German Research Foundation (Collaborative Research Centre TRR160, Project DFH/UFA CDFA05-06 and Project 383065199), the Federal Ministry of Education and Research (Project Q. Link.X/funding number 16KIS0867), the Danish Center of Excellence Hy-Q, (grant number DNRF139) and the European Research Council within the ERC Advanced Grant "Scale".Original publication
Matthias C. Löbl, Clemens Spinnler, Alisa Javadi, Liang Zhai, Giang N. Nguyen, Julian Ritzmann, Leonardo Midolo, Peter Lodahl, Andreas D. Wieck, Arne Ludwig, Richard J. Warburton: Radiative Auger process in the single-photon limit, in: Nature Nanotechnology, 2020, DOI: 10.1038/s41565-020-0697-2Press contact
Prof. Dr. Andreas Wieck
Chair of Applied Solid State Physics
Faculty of Physics and Astronomy
Ruhr University Bochum
Phone: +49 234 32 26726
e-mail: andreas.wieck@rub.deDr. Arne Ludwig
Chair of Solid State Physics
Faculty of Physics and Astronomy
Ruhr University Bochum
Phone: +49 234 32 25864
e-mail: arne.ludwig@rub.de - CAR becomes MOTION
25th June 2020,
Institute Realigns Itself.
The CAR Institute of University of Duisburg-Essen (UDE) is realigning itself and becoming considerably larger. "In the future, the fields of work will not be limited to automotive engineering and economics, but will also include other areas of mobility. These include ship technology and transport logistics," explains Prof. Dr. Dieter Schramm, Dean of Engineering Sciences. Consequently, additional members will strengthen the institute and it will be given a new name: MOTION - MObility TransformaTION.
In this way, the Institute is taking into account the fact that new technologies today can no longer be easily assigned to specific industries. "Methods that are developed and used for the autonomous driving of cars can also be applied in inland navigation, for example. And transport logistics also reacts to the networked world and asks for energy-efficient and automated systems," Schramm explains the new orientation. "Our faculty has outstanding expertise in this area - in research and teaching, both nationally and internationally.
Among the new members of MOTION is Prof. Dr. Ellen Enkel, who will also play an important role in the institute's executive board. The expert for general business administration and mobility researches collaborative business models as well as digitalisation in the automotive and aviation industry. Prof. Schramm was elected spokesperson of the institute. He succeeds Prof. Dr. Ferdinand Dudenhöffer, who has withdrawn from the institute.
Further information:
Prof. Dr. Dieter Schramm, Engineering/Mechatronics, Tel. 0203/37 9-3275, dieter.schramm@uni-due.de - Project Nominated for EU-Award
23rd June 2020,
Chipless Radio Labels for Printing.
They are printable, flexible and do not require a chip: Radio labels based on silicon nanoparticles from the NanoEnergieTechnikZentrum (NETZ) at University of Duisburg-Essen (UDE). They were developed in the "DruIDe" project, which is led by four UDE engineers. DruIDe has now been nominated for the EU "REGIO STARS 2020" award. The final decision is made by online voting.
In future, chip-less labels made of nanosilicon will make it possible to detect entire carloads with a single scan. With the barcodes commonly used up to now, each package must be recorded and scanned individually. But the new technology not only makes life easier for logisticians and parcel carriers, it also saves a lot of material: trees. Because, unlike barcodes, the RFID label ("radio-frequency identification") is reusable, and so is the parcel. Since it does not require a chip, its price is around €0.01, which is around five times less than its conventional counterpart.
Now the project, headed by Professors Niels Benson, Thomas Kaiser, Daniel Erni and Roland Schmechel - three of them from the Center for Nanointegration Duisburg-Essen (CENIDE) - has been nominated in the category "Industrial transition for a Smart Europe". The team includes five other institutions, including the University of Twente (Netherlands).
The REGIO STARS Awards are presented annually by the Directorate-General for Regional Policy and Urban Development of the European Commission. The aim of the competition is to identify best practice in regional development and to reward innovative EU-funded projects that can be attractive and inspiring for other regions and project managers.
The jury will select up to five finalists per category, which will be announced on 9 July.
To vote: https://regiostarsawards.eu (DruIDe is in the first, yellow-orange category; click on the heart to vote)
Further information:
Prof. Dr. Daniel Erni, General and Theoretical Electrical Engineering, Tel. 0203 / 37 9-4212, daniel.erni@uni-due.de - Dies academicus 2020
12th June 2020,
UDE chemist awarded.
© privatDr. Vi Tran from University of Duisburg-Essen (UDE) was awarded for the best doctorate in 2019 in the Faculty of Chemistry. She was a PhD student in the working group of Materials Chain member Prof. Sebastian Schlücker. This year, the Dies academicus could not take place in front of an audience as usual, so congratulations were sent to the winners by video.
In her work she developed a highly sensitive and quantitative rapid test (LFA) for patient-oriented laboratory diagnostics. Tests of this kind can be carried out and directly evaluated in the presence of the patient, and do not have to go to a central laboratory. This is particularly important in emergency medicine, for example.
Tran combined the previous test method with the advantages of surface-enhanced Raman spectroscopy (SERS). The result: By using SERS-active nanoparticles as markers and a portable Raman/SERS reader developed in the research group, a rapid test was realized that is highly sensitive and quantifiable and enables parallel detection through multiplexing. This is a major developmental advance for the LFA technology.
Every year, the UDE's Dies academicus awards prizes for the best bachelor's and master's theses and outstanding doctorates. This year the event was held online due to the current situation.
- Evolution Underground
10th June 2020,
Potential Beginning of Life Simulated in Lab.
High-pressure chamber where the evolutionary experiments take place. Its diameter is about 6 cm.
© C. Mayer, CENIDE/UDEDid life originate not on the ground but underground? Scientists at University of Duisburg-Essen (UDE) have substantiated their theory that first life could have begun deep in the earth's crust. In their experiments, structures that were inanimate developed survival strategies within a short time.
In the beginning there was the vesicle: A self-generated bubble similar to a soap bubble, enclosed by a membrane. It was surrounded by a liquid according to the recipe of the primeval soup, with a temperature of 40 to 80°C and increased pressure. Those are the conditions as they existed some 3.8 billion years ago and still do today – far down in the earth's crust.
With this experimental setup, chemist Christian Mayer from the Center for Nanointegration (CENIDE) and geologist Ulrich Schreiber, also a professor at the UDE, have simulated water-filled crevices in the earth's bowels as well as geothermal sources. In their laboratory experiment, they created and disintegrated a total of 1,500 vesicle generations within two weeks.
The researchers discovered that some vesicles survived the generation change because they had embedded certain protein precursors from the primordial soup into their membrane. This made them more stable, smaller and – most importantly – their membrane became slightly more permeable.
Forwarding Functions to Subsequent Generations
"We concluded that this way the vesicles were able to compensate for destructive pressure," explains Mayer. "As a survival strategy, if you will." Even if such a vesicle was destroyed, the next generation took up the protein structure. In this way, it adopted a function from its predecessors – similar to classical inheritance.
Mayer and Schreiber are certain that they have at least shown the way to a preliminary stage of life. "As we have simulated in time-lapse, billions of years ago such vesicles might have become stable enough to come to the surface during geyser eruptions," said Schreiber. Over time, other functions might have been added until the first cell was formed.
Mayer summarizes: "We suspect that this type of molecular evolution in depth took place parallel to other mechanisms or temporally displaced from them."
Further Information:
Prof. Christian Mayer, Physical Chemistry, +49 201/18 3-2570, christian.mayer@uni-due.deEditor: Birte Vierjahn, +49 203/37 9-8176, birte.vierjahn@uni-due.de
- An Exceptional Cobalt Compound
9th June 2020,
Material Research.
David Zanders and Anjana Devi (right) are excited about this extraordinary discovery.
© RUB/MarquardIn the search for small but stable cobalt compounds, an international team has discovered an exciting complex for materials research that has not been seen for almost 50 years.
A research team from the Ruhr-Universität Bochum (RUB) and Carleton University in Ottawa has produced a novel, highly versatile cobalt compound. The molecules of the compound are stable, spatially very compact and have a low molecular weight so that they can be evaporated for the production of thin films. This makes them interesting for applications such as battery or accumulator production. Due to their special geometry, the compound also has a very unusual spin configuration from ½. Such a cobalt compound was last described in 1972. The team reports in the journal Angewandte Chemie International Edition of May 5, 2020.The geometry makes the difference
"The few known cobalt (IV) compounds are unstable at high temperatures and very sensitive to air and moisture. This makes them difficult to use as study systems or in materials synthesis," explains first author David Zanders from the Bochum-based Chemistry of Inorganic Materials Group of Prof. Dr. Anjana Devi. In the course of his binational doctorate, which was sealed by a cotutelle agreement between the RUB and Carleton University, he and his Canadian colleagues Prof. Dr. Seán Barry and Goran Bačić discovered a cobalt(IV) compound that has an unusual stability.
Using theoretical studies, the team was able to demonstrate that an almost perpendicular embedding of the central cobalt atom in a tetrahedrally arranged environment of connected atoms - so-called ligands - is the key to stabilizing the compound. This special geometric order within the molecules of the new compound also forces the extraordinary electron spin of the central cobalt atom. "Under these special circumstances, the spin can only be ½," explains David Zanders. A cobalt compound with this spin state and similar geometry has not been described for almost 50 years.
With a series of experiments, the team also showed that the compound - untypical of cobalt(IV) - has a high volatility and can be evaporated at temperatures up to 200 degrees Celsius with almost no decomposition.
A promising candidate for ultra-thin layers
Individual molecules of the compound dock onto surfaces in a controllable manner after evaporation. "This fulfils the most important criterion of a potential precursor for atomic layer deposition," Seán Barry notes. "This process is becoming increasingly important in industry in the production of materials, and our cobalt(IV) compound is the first of its kind suitable for this purpose". "Since the highly valent oxides and sulfides of cobalt are considered to have great potential in modern battery and microelectronics, for example, our discovery is all the more exciting," adds Anjana Devi. The electrodes in rechargeable batteries lose stability with the increasing number of charging and discharging processes, which is why research is looking for more stable and thus more durable materials for them. The use of new methods for their production is also in focus.
"This binational collaboration is based on David Zanders' own initiative and has combined the ingenuity and complementary expertise of chemists from Bochum and Ottawa. This has produced something unexpected and was the key to success," summarizes Anjana Devi.
Funding
The work was funded by the German Research Foundation within the framework of the Collaborative Research Centre/Transregios 87 and by the Natural Sciences and Engineering Research Council of Canada in the project RGPIN-2019-06213. David Zanders received a Kekulé grant from the German Chemical Industry Association and a one-year scholarship from the German Academic Exchange Service.Original publication
David Zanders, Goran Bačić, Dominique Leckie, Domilola O. Odegbesan, Jeremy Rawson, Jaseon D. Masuda, Anjana Devi, Seàn T. Barry: A rare low-spin Co(IV) Bis(β-silyldiamide) with high thermal stability: Steric enforcement of a doublet configuration, in: Angewandte Chemie International Edition, 2020, DOI: 10.1002/anie.202001518Press contact
Prof. Dr. Anjana Devi, David Zanders
Chemistry of inorganic materials
Chair of Inorganic Chemistry II
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 24167
e-mail: anjana.devi@rub.de
david.zanders@rub.de - Physics Collaborative Research Centre Prolonged
29th May 2020,
Flip-book in a Split Second.
Vortex formation of light: The pattern represents the electric field that is formed for a few femtoseconds at the centre of a spiral on a gold surface when illuminated with circularly polarised
SFB 1242, Dreher/JanoschkaRapidly changing materials and measuring techniques in the femtosecond range: These are the core aspects of the Collaborative Research Centre 1242 of the Faculty of Physics at University of Duisburg-Essen (UDE). The German Research Foundation (DFG) is funding it for another four years with €12 million.
The Collaborative Research Centre 1242 "Non-equilibrium dynamics of condensed matter in the time domain" from the Faculty of Physics deals with solids and their interfaces, which are brought into an excited state extremely quickly by an external stimulus. The scientists observe the development of this excitation over time using measuring methods that allow them to follow the state of a sample in individual, minute time steps. The sum of all steps creates an overall picture of the process, just like in a flipbook.
Can extraordinary material properties be created in this way?
New impulses and concepts for science and for new applications can result from this. In the first funding period, the aim was to develop methods to trace and understand the path from excitation back to equilibrium. "Now our goal is to specifically influence the mechanisms behind this," explains spokesperson Professor Uwe Bovensiepen. "For example, we are wondering whether unusual material properties arise that only occur after short-term excitation. Or whether there are material modifications that keep the excitation alive over a longer period of time
The pump-probe method is the central method of the SFB, which cooperates closely with the Center for Nanointegration Duisburg-Essen (CENIDE): The system is excited with a first ultrashort laser pulse. A second, read-out laser pulse follows at variable intervals of a few attoseconds to picoseconds. If the time interval between excitation (pump) and detection (probe) is increased for each approach, the sum of the data results in a highly resolved process sequence.
The cooperation with the Interdisciplinary Center for Analytics on the Nanoscale (ICAN) is crucial in this respect, since the instruments available there and the specialized personnel enable the sophisticated preparation and characterization of the samples.
Further information:
Prof. Uwe Bovensiepen, Faculty of Physics, Tel. 0203 37 9-4566, uwe.bovensiepen@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Distinguished Lecture Award in Thermodynamics and Transport Properties
26th May 2020,
Another High Distinction for Prof. Gabriele Sadowski.
© Lutz Kampert/TU DortmundHigh distinction for Prof. Gabriele Sadowski from the Faculty of Biochemical and Chemical Engineering at TU Dortmund University: The European Federation of Chemical Engineering (Fédération Européenne de Génie Chimique/EFCE) awarded her as the first woman the "Distinguished Lecture Award in Thermodynamics and Transport Properties".
The EFCE Department of Thermodynamics and Transport Properties thus honoured the internationally recognised achievements of Prof. Sadowski in the field of modelling and experimental investigation of material properties. The award jury stated: "She is an international leader in the field of thermodynamics. She also does important work for our community and is a great teacher and mentor for young scientists".
Gabriele Sadowski has been full professor of thermodynamics at the TU Dortmund University since 2001. She is also a member of the Cluster of Excellence RESOLV, the NRW Academy of Sciences and Arts and the German Academy of Science and Engineering acatech. Since 2016 she has also been Vice Rector Research at the TU Dortmund University.
More than 230 articles published in scientific journals
Her main research focus is the modelling and investigation of the properties of complex substances and their mixtures, especially those with polymers, pharmaceutical substances and chemical and biological reactions.
Prof. Sadowski has published more than 230 articles in high-ranking international journals, which have been cited more than 8000 times. She has already received several awards for her research, including the Arnold Eucken Prize of the German Society for Process and Chemical Engineering (1999). In 2011, she was one of the ten scientists to receive the Gottfried Wilhelm Leibniz Prize, the most highly endowed international research award.
Contact person for further questions:
Prof. Dr. Gabriele Sadowski
Phone: +49 231 755 2635
fax: +49 231 755 2572
e-mail: gabriele.sadowski@tu-dortmund.de
Chair of Thermodynamics
Faculty of Bio- and Chemical Engineering - How interstitial ordering affects high-strength steels
14th May 2020,
Scientists from the Max-Planck-Institut für Eisenforschung and Ruhr-Universität Bochum publish their recent findings in Nature Materials.
The distribution and ordering of carbon atoms in a martensitic steel play an important role in the steel’s performance. The chemical potential of carbon in the system, which strongly depends on the carbon ordering in the lattice, determines this distribution. While for small carbon concentration the balance is in favour of the extended defects, the interstitial lattice sites are energetically preferred for larger concentrations.
© Xie Zhang, Max-Planck-Institut für Eisenforschung GmbHThe performance of materials is strongly influenced by their alloying elements: Adding elements beyond the basic composition of the alloy can strongly influence the properties and performance of it. In practice, it is not only important which elements are added, but also to which amounts and how they order in the host lattice. For the fundamental basic composition of any steel – iron and carbon - the concentration and ordering of carbon atoms and their interaction with the iron host lattice in martensitic steels was analysed by a team of scientists from the Max-Planck-Institut für Eisenforschung (MPIE) and Ruhr-Universität Bochum (RUB). The scientists examined the mechanisms of collective interstitial ordering in Fe-C steels and determined how anharmonicity and segregation affect the ordering mechanism and consequently, the material’s performance. Their recent findings were published in Nature Materials.
“When carbon atoms enter the iron host lattice of martensitic steels, they diffuse between the iron atoms and do not take over the iron atoms’ positions in the host lattice. Nevertheless, they create strain fields influencing the whole lattice. Understanding the mechanism of the resulting interstitial ordering is a key to designing ultra-high performance steels as they gain their strength from the martensite formation, thus, from the collective interstitial ordering”, explains Dr. Tilmann Hickel. Hickel is head of the group “Computational Phase Studies” at the MPIE and was the main supervisor of Dr. Xie Zhang, the first author of the publication. Each interstitial atom, due to its size and chemical interaction with atoms of the host lattice, creates a local strain field that displaces its neighbouring host atoms away from their original lattice positions. “Imagine inserting a wooden stick into sand at the beach and watching how the stick displaces the grains of sand surrounding it. The same happens when we add carbon to the iron host lattice. The carbon interstitials, find their way through the host lattice, order in energetically favourable places and distort and harden the previous structure.”, explains Hickel. A high concentration of interstitials leads to ordering/disordering phenomena and lattice distortions, thus influencing the steels’ bulk performance.
The research team identified two components that influence the interstitial ordering. The first one results from the anharmonicity caused by the strain fields in the Fe lattice. “Due to this anharmonicity, the critical C concentration for an order-disorder transformation is decreased. To understand the displacement of the Fe atoms at different distances, we must consider the anharmonic contribution in the first neighbour position of a C interstitial.”, explains Dr. Jutta Rogal from the Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) at Ruhr-Universität Bochum.
The second component that influences the interstitial ordering is the segregation of C to extended defects. This segregation takes place at low C concentrations and is suppressed at high C concentrations due to a lowering of the C chemical potential in ordered martensite. The chemical potential of C in Fe-C martensite gradually increases with increasing C concentration until 0.8 at.% are reached. Then it rapidly decreases due to the order-disorder transition.
Both components, the level of anharmonicity and the segregation behaviour, are decisive for the order-disorder transition. “An unexpected outcome of the study was that it is not sufficient to analyse only the arrangement of the carbon atoms in bulk. Rather, a strong competition between the carbon concentration in the bulk and its segregation to extended defects occurs. Only with this insight it was possible to gain a comprehensive understanding of the order-disorder transition. This competition decreases with an increasing concentration of carbon interstitials, as extended defects can incorporate interstitials only to a limited amount. The exact concentration depends on the density of the defects. In our calculations and confirmed by experiments, disordered martensite is triggered by a carbon concentration in the range between 0.8 at.% and 2.6 at.%. Above 2.6 at.% ordered martensite is formed, which provides a superior strength to steels. Below 0.8 at.%, carbon atoms segregate to dislocations in grain boundaries”, explains Prof. Jörg Neugebauer, director of the department Computational Materials Design at MPIE. The theoretical calculations were confirmed by transmission electron microscopy and atom probe tomography measurements performed at Ruhr-Universität Bochum.
In general, the exact critical C concentration depends on the microstructure of the material and the binding energy between C and a specific extended defect. The shown critical concentration range of 0.8 at.% and 2.6 at.% is not universal, but depends on the sample and its extended defects. However, the critical concentrations can be precisely calculated if a) the exact binding energy between C and the extended defect, and b) the maximum C concentration that can be included by the extended defect, are known. The MPIE and RUB team showed the decisive role anharmonicity and segregation play regarding the mechanism of interstitial ordering, using the Fe-C alloys as a model for other relevant systems. Including anharmonic effects into order-disorder phase transitions provides a new level of predictive materials modelling, paving the way to designing ultra-high-performance steels.
The research was supported by the German Research Foundation within the DFG-ANR project C-TRAM.
Author: Yasmin Ahmed Salem - Suitability of Imaging Techniques Proven
11th May 2020,
WITec Paper Award.
Model of an ArteryA publication in which PhD student Elzbieta Stepula from the working group of Materials Chain member Prof. Sebastian Schlücker (University of Duisburg-Essen) is involved was awarded the silver WITec Paper Award. This makes it one of three award-winning papers out of 113 submissions.
Under the title "ImmunoSERS microscopy for the detection of smooth muscle cells in atherosclerotic plaques", a team led by a research group from the Jagiellonian University in Krakow (Poland) characterizes atherosclerotic plaques using iSERS microscopy.
Atherosclerotic plaques form on arterial walls and constrict the blood vessels. Monitoring their stability is clinically relevant because if they become loose, they can lead to a stroke or heart attack. Since smooth muscle cells play an important role in stabilizing the plaques, they can serve as markers for their stability.
This excellent biomedical publication establishes iSERS microscopy as a promising technique for the localisation and quantification of smooth muscle cells in atherosclerotic plaques.
The WITec Paper Award is presented annually to three outstanding scientific publications whose data were generated using a microscope from the company.
Original publication:
E. Wiercigroch, E. Stepula, L. Mateuszuk, Y. Zhang, M. Baranska, S. Chlopicki, S. Schlücker and K. Malek
"ImmunoSERS Microscopy for the detection of smooth muscle cells in atherosclerotic plaques"
Biosensors and Bioelectronics 133: 79-85 (2019)
doi.org/10.1016/j.bios.2019.02.068Further information:
Elzbieta Stepula, Physical Chemistry, Tel. 0201 18 3-4917, elzbieta.stepula@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Popular Paper from Engineers
11th May 2020,
Awarded by the AIChE Journal.
A publication from the working group of Materials Chain member Prof. Hartmut Wiggers in the AICHe Journal is one of the most frequently read papers of the journal in the years 2018/2019.
Under the title "Spray-flame synthesis of La(Fe, Co)O3 nano-perovskites from metal nitrates" the team around first author Steven Angel published in the journal of the American Institute of Chemical Engineers.
Hartmut Wiggers' research group operates, among other things, the nanoparticle synthesis facilities at the NanoEnergieTechnikZentrum (NETZ) on the Duisburg campus of the University of Duisburg-Essen.
Original publication:
S. Angel, J. Neises, M. Dreyer, K. Friedel Ortega, M. Behrens, Y. Wang, H. Arandiyan, C. Schulz, H. Wiggers
"Spray-flame synthesis of La(Fe, Co)O3 nano-perovskites from metal nitrates"
AIChE Year 2020; 66:e16748
https://doi.org/10.1002/aic.16748Further information:
Steven Angel, IVG, phone 0203 37 9-379 8084, steven.angel-canas@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Nature Research Awards Prizes
7th May 2020,
Innovative Science.
Researchers and all those involved in the STEM area for girls and women can still apply for the Nature Research Awards for Inspiring and Innovating Science until 14 June. They are endowed with 30,000 US dollars each.
For the award in the Scientific Achievement category, young female researchers are sought who "identify themselves as women and have made an exceptional contribution to scientific progress, sometimes despite adverse circumstances.
In the Science Outreach category, the award is given to an initiative that inspires girls and young women to take up MINT subjects or encourages women to pursue a scientific career.
Further information:
https://group.springernature.com/de/group/media/nature-research-awards-for-inspiring-and-innovating-science/17901168Editor: Ulrike Eichweber
- Kristina Tschulik is a Member of the NRW Academy of Sciences
6th May 2020,
Chemistry.
© Mathies Evers
The election is a special honour for outstanding researchers.
Prof. Kristina Tschulik, chemist at the Ruhr-Universität Bochum (RUB), will become a new member of the North Rhine-Westphalian Academy of Sciences and Arts. The head of the strongly interdisciplinary research group Electrochemistry and Nanoscale Materials was elected to the class for engineering and economics. Her work focuses on electrochemical materials research. In total, the Academy is taking on 15 new members from all over NRW this year. The admission is a special distinction for outstanding researchers.About the person
Kristina Tschulik studied chemistry at the Technical University of Dresden, where she also completed her doctorate in 2012. During her doctorate, she worked at the Leibniz Institute for Solid State and Materials Research and then as a postdoctoral "Marie Curie Intra European Fellow" at the University of Oxford. After a stay abroad in Johannesburg, South Africa, she joined the RUB in September 2015, where she initially strengthened the team of the Resolv Cluster of Excellence as junior professor, funded by the NRW Returning Professor Programme of the Ministry of Innovation, Science and Research. Kristina Tschulik was a visiting professor at the Université Paris Diderot in France in 2017 and has been head of the Chair of Analytical Chemistry II at the RUB since June 2018.The Academy
The North Rhine-Westphalian Academy of Sciences and Arts celebrates its 50th anniversary in 2020. Founded in 1970 as the successor to the Research Association of the State of North Rhine-Westphalia, the Academy has been uniting the leading researchers from NRW under its roof for half a century. For more than ten years, its members have also included renowned artists. The Academy promotes dialogue across disciplinary boundaries and generations as well as exchange with society.Press contact
Prof. Dr. Kristina Tschulik
Chair of Analytical Chemistry II
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 29433
e-mail: nanoec@rub.deEditor: Meike Drießen
- More Courage for Creativity
26th April 2020,
Materials Science.
Sometimes scientists should think more around the corner, says Prof. Dr. Tong Li.
© Damian GorczanyThe achievements in the field of artificial intelligence make engineer Tong Li pensive about human thinking habits.
In 2017, researchers have created an artificial intelligence that has independently learned the Chinese board game "Go" without human guidance or prior knowledge. In just 40 days, the computer became the best Go player in the world - an incredible achievement. Surprisingly, the artificial intelligence used moves that humans had never used before. I was very impressed by this. I wondered whether our prior knowledge sometimes limits our creativity - and can therefore also be an obstacle on the path to new scientific knowledge.
No theory provided an explanation
Here is an example from my own research in which I characterize the structure and chemical properties of high-performance materials: One goal of materials science is to tailor new materials with special properties. But sometimes it is difficult to understand why a material behaves the way it does. We have tried to explain the behaviour of complex material systems using existing and widely accepted theories. But none provided an answer.
Sometimes our previous knowledge steers us in a completely wrong direction. In fact, technical developments actually give us the chance to verify or modify theories. We just need to think around the corner more and be more courageous in order to develop our creativity.
Editor: Tong Li
- New Type of Microscopy Developed
24th April 2020,
Publication in Science on Nanooptics.
© Tim Davis
Graphical representation of optical skyrmions at a point in time when their electric fields in the center point out of the surface. The distance between adjacent skyrmions corresponds to the plasmon wavelength of 780 nanometers.The duration of their momentary image is related to one second in the same way as one second to the age of the universe: Together with the Australian scientist Tim Davis and the research group of Harald Gießen (University of Stuttgart), physicists at University of Duisburg-Essen (UDE) have developed ultrafast vector microscopy, a method of determining electric fields on surfaces with high temporal and spatial resolution. This method was used to trace the dynamics of optical skyrmions in time for the first time. The renowned journal "Science" publishes this breakthrough in nanooptics in its current issue.
Interactions between light and matter are the basis of nanooptics. Researchers working with it can use spectroscopic and microscopic methods to observe and influence the properties and states of tiny structures and even individual molecules. As with optical computers, which are still in their infancy: since their structures are sometimes much smaller than the wavelength of light, tricks such as nanoantennas are needed to effectively couple it in. But it is very difficult to analyze the electric fields around such structures in space and time.
With vector microscopy based on time-resolved 2-photon photoemission microscopy, a team of physicists led by UDE Professor Frank-J. Meyer zu Heringdorf, the Australian experts in nanooptics Dr. Timothy J. Davis and Professor Harald Gießen have now achieved a pioneering achievement: they have been able to determine the electrical fields on a metal surface with pinpoint accuracy and time precision - down to 10 nanometers local resolution and in the sub-femtosecond range.
Ultra-short laser pulses combined with vector calculation
For this purpose, they used gold microcrystallites on whose surface they generated a surface plasmon polariton after nanostructuring by an ultrashort laser pulse; an electron wave that propagates on the surface. A few femtoseconds after excitation, a second laser pulse reads the electric field of the wave. However, the interrogating pulse can only analyze the component that is equally polarized, i.e. where the electric field of the interrogating laser pulse and that of the plasmon on the surface point in the same direction.
The scientists reconstructed the field vectors by determining two field components in two experiments with different interrogation polarizations. The third could then be calculated from the first two using the Maxwell equations. "This is a real breakthrough," explains Meyer zu Heringdorf, member of the UDE Collaborative Research Centre "Non-equilibrium dynamics of condensed matter in the time domain". "In this way, every point of an electric field on a surface can be observed at any time - in the smallest structures."
Oscillating skyrmions observed
Due to their promising properties in magnetic systems, research is currently investigating whether the magnetic properties of skyrmions can also be transferred to optics. The researchers have therefore demonstrated the value of the method they have developed by tracing the dynamics of optical skyrmions in time for the first time.
To this end, the team created plasmons on the gold surface whose electric fields formed optical skyrmions (see picture). The researchers then systematically increased the time interval between exciting and detecting laser pulses by about 100 attoseconds. A film of the up and down swinging skyrmions resulted from the sequence of the reconstructed field images.
Since the method is universally applicable to electric fields on surfaces, vector microscopy can be used to investigate field distributions in optical nanostructures with a precision that would have been unthinkable just a few years ago.
Original publication:
T.J. Davis, D. Janoschka, P. Dreher, B. Frank, F.-J. Meyer zu Heringdorf, H. Giessen
"Ultrafast vector imaging of plasmonic skyrmion dynamics with deep subwavelength resolution"
Science 368, 6489 (2020)
DOI: 10,1126/science.aba6415Further information:
Prof. Dr. Frank-J. Meyer zu Heringdorf, Experimental Physics, Tel. 0203 37 9-1465, meyerzh@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Prof. Manfred Bayer Becomes the New Rector of the TU Dortmund University
24th April 2020,
University Election Assembly elects Physicists with a Large Majority.
© Jürgen Huhn/TU Dortmund
Prof. Manfred BayerOn 24 April 2020, a new Rector was elected at the TU Dortmund University: Prof. Manfred Bayer from the Faculty of Physics will succeed Rector Prof. Ursula Gather on September 1 and take over the office at the head of the university. He was previously Chairman of the Senate of the TU Dortmund University for around twelve years.
Under unusual conditions, the TU Dortmund University election meeting convened in the Audimax on 24 April: The committee consisting of the Senate and the University Council was allowed to meet despite the corona crisis, because the meeting for the rectorate election is considered a highly significant act of self-administration in terms of university policy and therefore does not fall under the ban on events in the Corona Protection Ordinance. The university's largest lecture hall, with 700 seats, was sufficiently dimensioned so that the approximately 60 members could keep sufficient distance from each other. The election assistants wore face masks and gloves when they brought the microphone into the rows to speak and count the ballots. The public could follow the election via live stream on the Internet. It was clear in advance that no one was allowed to shake hands with the elected candidate.
Numerous congratulations
Prof. Manfred Bayer immediately achieved an overwhelming majority in both parts of the committee: The University Council voted unanimously in his favor, and 26 of the 27 members of the Senate voted for him. "I am delighted that in Manfred Bayer we have been able to recruit a scientist and university lecturer of top international standing for the post of rector," said Professor Ernst Rank, Chairman of the University Council. "My colleague Manfred Bayer has earned the respect of all four groups at the university as a long-standing Chairman of the Senate," said acting Senate Chairman Prof. Lorenz Schwachhöfer. It is thanks to Bayer's moderation skills that the Senate has remained a united body in the debate on a new basic order for the university.
The current incumbent, Prof. Ursula Gather, also congratulated her successor warmly on his election: "I am very pleased that I can hand over the office to such an experienced colleague," she said, "I wish him a happy hand at all times. Chancellor Albrecht Ehlers joined in the congratulations: "I have already worked together with Mr. Bayer in his role as Chairman of the Senate. I am very much looking forward to continuing the pleasant and fruitful cooperation with him in this new constellation. While the Prorectors must resign from office with the Rector, the Chancellor continues his term of office in the Rectorate. Prof. Manfred Bayer himself gave an outlook on the direction in which he wants to steer the TU Dortmund University in the future: "The goal must be to further optimize the good conditions for students at the TU Dortmund University and at the same time to strengthen the high research potential in order to be able to compete successfully in the market.
Outstanding research and international networking
Born in Franconia, Prof. Manfred Bayer accepted a call to the professorship "Experimental Physics with a focus on Spectroscopy of Condensed Matter" at the TU Dortmund University in 2002 at the age of 36. He regularly publishes his outstanding research results in high-ranking specialist journals. Internationally networked, he cultivates in particular the cooperation with St. Petersburg as spokesman of the first German-Russian Collaborative Research Centre of the German Research Foundation. He has received several international awards for his excellent research, including the title of Fellow of the American Physical Society (2012) and membership of the Russian Academy of Sciences (2017).
As UA Ruhr Professor, Bayer is also in close contact with neighboring universities in the Ruhr region. As co-initiator of the popular lecture series "Between Buns and Borussia," he also knows how to inspire a broad audience for topics in physics. There is one thing he will miss from September 1, and Bayer already knows this: the view from the Physics Faculty of the world's most beautiful stadium.
Contact for further information:
Eva Prost
Phone: +49 231 755 2535
fax: +49 231 755 4664
e-mail: eva.prost@tu-dortmund.de
Unit 1 University Communication - Cheaper Production of Better Batteries
22nd April 2020,
EU Project.
© RUB, Marquard
Wolfgang Schuhmann and his team from the Centre for Electrochemistry at the RUB are involved in the EU projectBuilt-in sensors should help to make the production of batteries much cheaper.
Approximately one third of the production costs of rechargeable batteries is caused by the phase of the first charging, in which the battery has to be conditioned. In order to make this phase more efficient and thus make battery production much more cost-effective, the consortium of the "Nano-Bat" project is developing sensors that will monitor the processes taking place in the battery. The project involves a research team from the Centre for Electrochemistry at Ruhr University Bochum (RUB) headed by Prof. Wolfgang Schuhmann. The consortium of twelve partners under the leadership of the Austrian company Keysight Technologies has been funded by the European Commission with around 5 million euros for three years since 1 April 2020.
Insulating layer protects the solvent
One of the major cost drivers in the production of lithium-ion batteries is the very first charge. "You have to be very careful with this, and it can take up to a week," says Wolfgang Schuhmann. The reason for this lies in processes that take place in the battery. Both electrodes are embedded in a solvent. This so-called electrolyte decomposes at high voltages in the batteries. In the process, deposits form on the electrode, forming a solid layer only a few nanometers thick. Experts speak of the Solid Electrolyte Interphase, or SEI for short. "So this layer is actually a decomposition product, but necessary because once it has formed, the electrolyte does not decompose any further," explains Schuhmann.
Processes are still unexplored
The quality of the battery depends on the SEI layer; it must be neither too thick nor too thin or incomplete. Since the layer is formed during the first charge, everything must be correct. Voltage, temperature and many other factors influence the formation process. "But how all this must take place has not yet been sufficiently researched," says Schuhmann, "and you just can't look inside the battery.
The project team now wants to change this. Based on the basic understanding of the processes involved in the formation of the SEI layer, the researchers hope to develop nanosensors that will then be integrated into the batteries. These sensors could then be used to monitor the formation of the SEI layer. "The aim is to optimise the phase of the first charge so that the time required for this is drastically reduced," says Wolfgang Schuhmann.
Enormous economic potential
The sustainable storage of electrical energy is one of the greatest challenges of this century. The European Union considers battery production to be one of the future key industries with an estimated market potential of 250 billion euros by 2025.
Press contact
Prof. Dr. Wolfgang Schuhmann
Analytical chemistry
Center for Electrochemistry
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 26200
e-mail: wolfgang.schuhmann@rub.deEditor: Meike Drießen
- Inexpensive Alternative to Precious Metals
21st April 2020,
Stable Carbonyl Complex Prepared with Silicon.
© UDE
Molecular ashing: Reactive silylene captures carbon monoxide (CO).Carbon monoxide is used in many industrial processes where rare and expensive precious metals act as catalysts. A team of scientists from University of Duisburg-Essen (UDE) and University of Giessen has now been able to produce a carbonyl complex with the cheap semi-metal silicon for the first time. The scientific journal Nature Chemistry reports.
Carbonyl complexes, i.e. compounds of carbon monoxide (CO) with a so-called transition metal such as iron, have become indispensable in synthetic chemistry and catalysis, e.g. for the production of fuels. A team led by the chemists Prof. Stephan Schulz (UDE) and Prof. Peter R. Schreiner (Justus Liebig University Gießen, JLU) has now been able to demonstrate for the first time that such complexes can also be produced with main group elements such as the semi-metal silicon.
Everyone knows silicon oxide as sand. In this form, each silicon atom forms four bonds with neighbouring atoms. In the laboratory it is possible to reduce the metalloid to a two-bonded and therefore quite reactive species, the "silylene". The researchers were able to show that under certain conditions this actually bonds with carbon monoxide to form the first carbonyl complex stable at room temperature. In future, it is to be used for CO transfer reactions.
Original publication:
Chelladurai Ganesamoorthy, Juliane Schoening, Christoph Wölper, Lijuan Song, Peter R. Schreiner, and Stephan Schulz
"A room-temperature stable silicon carbonyl complex."
Nature Chem. 2020, 12.
DOI: 10.1038/s41557-020-0456-xFurther information:
Prof. Stephan Schulz, Faculty of Chemistry, Tel. 0201/18 3-4635, stephan.schulz@uni-due.deEditor: Birte Vierjahn, Tel. 0203/37 9-8176, birte.vierjahn@uni-due.de
- Changing Material Properties by Stretching
16th April 2020,
Science Publication on New Technology.
© Seung Sae Hong
Charge-ordered phase of the lanthanum-calcium-manganese oxideOxides are ceramics that break brittle under mechanical stress, in contrast to metals, which are easily deformable. An international team of scientists, including theoretical physicists from University of Duisburg-Essen, has now succeeded in producing membranes made of oxides that can withstand extreme tensions of up to 8 percent.
If the distances between the atoms are stretched, the electrons can localize and new types of properties are created, such as in this specific case a transition from a conducting to an insulating state. This breakthrough published in "Science" may in future be used to specifically design the functionality of materials - for sensors or detectors, for example.
Together with colleagues from Northwestern University (USA), Manish Verma and Prof. Rossitza Pentcheva have investigated the causes and underlying mechanisms for the behavior of the material lanthanum-calcium-manganese oxide (La1-xCaxMnO3, LCMO) under extreme tensile stress using density functional theory calculations. The physicists were able to show that LCMO exhibits metallic and ferromagnetic properties in the normal state, but changes into an insulator with antiferromagnetic order under tensile stress of 5 percent. This insulator is characterized by a stripe charge order of Mn3+ and Mn4+ ions.
The statistical distribution of the lanthanum and calcium ions required large simulation cells and was simulated on the UDE's high-performance computer "MagnitUDE".
Detailed press release of the responsible Stanford University: https://www6.slac.stanford.edu/news/2020-04-02-new-way-fine-tune-exotic-materials-thin-stretch-and-clamp.aspx
Original publication: Seung Sae Hong et al., Science, 5 April 2020
Further information:
Prof. Dr. Rossitza Pentcheva, Computational Materials Physics, Tel. 0203 37 9-2238, rossitza.pentcheva@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Magnetisation by Light
8th April 2020,
Publication in Nano Letters.
© S. Lorenz et al., Nano Letters 20, 1896 (2020)
Schematic representation of photoluminescence spectroscopy on a single colloidal nanoparticle. The light-induced magnetization is studied by applying a magnetic field in different spatial directions.Generating magnetism on demand and without electricity - in the world of doped nanocrystals this is not science fiction, but feasible. A breakthrough in this field was recently achieved by the team from the "Materials of Electrical Engineering" chair at University of Duisburg-Essen with colleagues from University of Washington in Seattle (USA). They published their results in the scientific journal "Nano Letters".
Using spectroscopy on individual nanoparticles in a rotating magnetic field, the scientists showed how light-induced magnetism can be specifically aligned.
The chair's expertise in this field will continue to be used in the future. To this end, the German Research Foundation (DFG) has approved a new project entitled "Investigation of anisotropic spin phenomena in doped nanocrystals using luminescence spectroscopy on single particles in a vector magnetic field" for a period of three years.
Original publication: Lorenz et al., Nano Letters 20, 1896 (2020).
Further information and editing:
Severin Lorenz, Materials of Electrical Engineering, Tel. 0203 37 9-3191, severin.lorenz@uni-due.de - UDE and Leibniz Institute Establish Joint Lab
6th April 2020,
Together to Higher Frequencies.
© UDE / ZHO
Epitaxy system for the production of semiconductor materials. A new one, especially for indium phosphide, is currently being installed at the ZHO.Rapid data transmission, medical examinations with harmless radiation: High-frequency technologies make it possible. Researchers at University of Duisburg-Essen (UDE) are working on the necessary semiconductor materials. In future, they will work even more closely with the Ferdinand Braun Institute, the Leibnitz Institute for High Frequency Technology in Berlin (FBH). A joint laboratory has now been launched.
6G Terahertz communication with more than 100 Gigabit/s data volume, state-of-the-art radars and other applications suitable for everyday use are not possible without semiconductor materials. One of them is indium phosphide (InP). This crystalline substance is important for high-frequency components, but it can only be produced in small quantities and at great expense. The Centre for Semiconductor Technology and Optoelectronics (ZHO) at the UDE is working to change this - among other things with a new production facility. A terahertz integration centre unique in Germany is currently being built here, which is being funded by the state and the EU with 6.5 million euros.
The semiconductor experts at UDE are now contributing their know-how to the "JointLab InP Devices". "In this way we want to develop circuits and modules for terahertz applications together with our colleagues in Berlin," explains Dr. Nils Weimann. The Professor of High Frequency Electronics is head of the new laboratory.
The picture shows an epitaxy system for the production of semiconductor materials. A new one, especially for indium phosphide, is currently being installed at the ZHO.
Further information:
http://www.bhe.uni-due.de/
Prof. Dr. Nils Weimann, Components of High Frequency Electronics, Tel. 0203/37 9-3391, nils.weimann@uni-due.deEditorial office: Ulrike Eichweber, Tel. 0203/37 9-2461, ulrike.eichweber@uni-due.de
- Successor to Professor A. Heinzel Wanted
3rd April 2020,
Position as Head of Chair and Affiliated Institute Advertised.
© JRF e.V.
Main Laboratory ZBTAt the University of Duisburg-Essen (UDE), a university professorship for "Energy Technology" is to be filled in the Department of Mechanical and Process Engineering of the Faculty of Engineering at the earliest possible date. This is linked to the scientific management of the Centre for Fuel Cell Technology (ZBT gGmbH). Applications are accepted until 15 May.
The applicants' research focus should be on electrochemical energy conversion and storage, e.g. fuel cells, electrolysis, hydrogen technology, batteries, system integration. Experience in the field of "sector coupling in energy technology systems" is desired.The professorship is linked to the scientific management of the Centre for Fuel Cell Technology (ZBT gGmbH), an affiliated institute of the University of Duisburg-Essen. Therefore, experience in industrial research or in corresponding cooperations for the technological implementation of research results with industry is required.
The ZBT gGmbH, with approx. 100 employees, is a wholly owned subsidiary of UDE and has uniquely equipped laboratories and research facilities. It is a member of the Johannes Rau Research Association of the State of NRW.
Further information:
https://www.uni-due.de/imperia/md/content/stellenmarkt/stellenangebote_an_universitaeten/professoren-juniorprofessoren_an_der_ude/2020/3184_ude_prof.pdfEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Ideal Reaction Chain from Model and Experiment
2nd April 2020,
From Plant Residue to Biofuel.
Straw as source material for biofuel
Sawdust, straw or grain husks can be converted as efficiently as possible into sustainable fuel using only one microorganism: Researchers from University of Duisburg-Essen (UDE) have made an important contribution to this. Their approach, consisting of experiments and theoretical simulation, supports biotechnological approaches and leads to a process that is already being used in production by the industrial partner and has been published in the journal "Nature Communications".
By definition, biofuel is produced from biological sources that could often also be used as food, such as corn, sugar beets or soybeans. Lignocellulose, on the other hand, which makes up the woody parts in plants, is often found as a waste product after harvest or in the sawmill and is also suitable.However, the path from plant residue to biofuel is via so-called hexoses or pentoses, i.e. sugars consisting of six or five carbon atoms, such as glucose and xylose. A microorganism can usually convert either one or the other. Fivefold sugars are a problem for common biotechnologically used microbes: even if they are equipped with the required enzymes, for example, intermediate products accumulate which paralyse the organism or inhibit subsequent reactions.
Preparation works in the test tube and in the microorganism
Therefore, scientists around UDE researchers Prof. Bettina Siebers and Dr. Jochen Niemeyer as well as Jacky Snoep (University of Stellenbosch, South Africa) have been studying the reaction chain of five enzymes in which xylose is converted into a valuable intermediate product on the way to biofuel: the Weimberg pathway. Their computer-generated model - each confirmed, corrected and optimised by the subsequent experiment - now makes it possible to design an optimal reaction chain in the test tube. It provides instructions for each individual enzyme: quantity, incubation time or possible required cofactors such as metal ions.
The industrial partner Sigma-Aldrich (Merck) already uses an enzyme of the Weimberg pathway in production. But the model is also available to other scientists via open source web platforms, because "fair data management is important to us," says Siebers.
The project was funded by the Mercator Research Center Ruhr (MERCUR) and the Federal Ministry of Education and Research (BMBF).
Further information:
Prof. Bettina Siebers, Molecular Enzyme Technology and Biochemistry, Tel. 0201/18 3-7061, bettina.siebers@uni-due.deEditor: Birte Vierjahn, Tel. 0203/37 9-2427, birte.vierjahn@uni-due.de
- Catalyst Materials that Recycle CO2
30th March 2020,
BMBF Funds Chemist with 1.4 Million Euros.
Aerial view of a production plantReuse plastic, glass and soon also CO2: Since March, Professor Corina Andronescu and her research group from University of Duisburg-Essen (UDE) have been developing industry-relevant catalyst materials. These materials convert carbon dioxide (CO2) into basic chemicals that serve as the basis for other products. The Federal Ministry of Education and Research is funding the project for five years with 1.4 million euros.
The MatGasDif project, short for "Nanomaterials as a basis for gas diffusion electrodes for highly selective CO2 reduction", aims to reduce the proportion of the greenhouse gas CO2 in our atmosphere. To this end, Andronescu and her team are researching new electrocatalysts that make it possible to reduce carbon dioxide electrochemically to ethanol or ethylene. These can then be used, for example, as solvents for fragrances or dyes, aromas, medicines or as biofuels.The goal of the researchers: a conversion process that is stable over the long term and as selective as possible, avoiding by-products as far as possible. To achieve this, they want to use catalyst materials from inexpensive, sustainable and readily available raw materials.
"The biggest challenge is to manufacture the catalysts and electrodes in such a way that really only the valuable target product is created, not a mixture of products," explains Andronescu. To do this, different catalyst materials are embedded in a carbon carrier material so that they can preferentially produce the desired product in a reaction cascade. "This concept is not yet known, we are breaking new ground here."
At the end of the project, a first finished prototype should be available, which is not only suitable for small laboratory scales, but above all for larger dimensions in industrial use.
MatGasDif is funded by the Federal Ministry of Education and Research within the "NanoMatFutur" competition. It enables young scientists to set up their own research group and to qualify for management tasks in industry and research.
Further information:
Prof. Dr. Corina Andronescu, Faculty of Chemistry, corina.andronescu@uni-due.deEditor: Sarah Heuser, sarah.heuser@uni-due.de
- Finding Optimal Materials Recipes Using AI
26th March 2020,
Bochum Researchers Develop Structure Zone Diagrams.
Sputtering system in which nanostructured layers are produced. © Lars BankoThe possible properties of nanostructured layers are countless - but how can you find the optimal one without long experimentation? A materials research team from Ruhr-Universität Bochum (RUB) tried a shortcut: Using a machine learning algorithm, the researchers were able to reliably predict the structural properties of such a layer. They report in the new journal "Communications Materials" from March 26, 2020.
Porous or dense - columns or fibers
In thin layer production, numerous manipulated variables determine the nature of the surface and thus its properties. Not only the composition of the layer, but also the process conditions during its formation play a role, such as temperature. All of this together creates a porous or dense layer in the coating, ensures that the atoms assemble into columns or fibers. "In order to find the optimal parameters for an application, until now you had to do countless experiments with different conditions and compositions, which is incredibly complex," explains Professor Alfred Ludwig, head of the chair Materials Discovery and Interfaces at RUB.
The results of such experiments are so-called structure zone diagrams, from which one can read off the surface of a certain composition resulting from certain process parameters. "Experienced scientists can then use this diagram to identify the most suitable location for an application and derive the corresponding parameters for the production of the appropriate layer," explains Ludwig. "All of this is an enormous effort and takes a lot of time."
Algorithm predicts surfaces
To shorten the path to the optimal material, the team relied on artificial intelligence, more precisely machine learning. PhD student Lars Banko, in collaboration with colleagues from the Interdisciplinary Center for Advanced Materials Simulation (ICAMS) at RUB, modified a so-called generative model. Then he trained this algorithm to generate images of the surface of a very well examined model layer made of aluminum, chromium and nitrogen using certain process parameters and thus to predict what the layer would look like under these corresponding conditions.
“We gave the algorithm a sufficient amount of experimental training data,” explains Lars Banko, “but not all the known data.” This allowed the researchers to compare the results of the calculations with those of experiments and examine how reliable the prediction of the algorithm had been. The results were convincing: "We combined five parameters in parallel and were able to look in five directions at the same time with the algorithm without having to do experiments," says Alfred Ludwig. "We have thus shown that the methods of machine learning can be transferred to materials research and can help to develop new materials in a more targeted manner."Funding: The work was funded by the Deutsche Forschungsgemeinschaft within the Collaborative Research Center/Transregio 87 "Pulsed high-performance plasmas for the synthesis of nanostructured functional layers", Project C2.
Original Publication: Lars Banko, Yury Lysogorskiy, Dario Grochla, Dennis Naujoks, Ralf Drautz, Alfred Ludwig: Predicting structure zone diagrams for thin film synthesis by generative machine learning, in: Communications Materials, 2020. DOI: 10.1038/s43246-020-0017-2
Editor: Meike Drießen Dezernat Hochschulkommunikation, Ruhr-Universität Bochum
Contact: Prof. Dr. Alfred Ludwig Materials Discovery and Interfaces Institut für Werkstoffe Fakultät für Maschinenbau Ruhr-Universität Bochum E Mail: alfred.ludwig@rub.de
- 3D Printing for the Automotive Industry
26th March 2020,
EUR 10.7 Million from the Federal Government.
Aerial Photography of CarsCompletely drive-ready cars cannot be printed from 3D printers. How the additive process could produce their plastic components is being investigated in the POLYLINE project by, among others, the Chair of Production Engineering at the University of Duisburg-Essen (UDE). Nationwide, 15 partners from science and industry are developing the digitized production line for the automotive industry. The project is funded by the Federal Ministry of Education and Research with 10.7 million euros for three years.
Additive manufacturing (AF) is intended to expand conventional production techniques such as machining or casting. In this process, the material is generated layer by layer from a powdery material by laser on the basis of digital design data (sintering). Even complex structures can thus be realized without much additional effort. So far, the process has only been used to a limited extent in mass production. This is due, among other things, to the digital data sets that are not available continuously at many interfaces. This makes monitoring the production process more difficult, and errors often occur.
The 3D printing experts at UDE around Prof. Gerd Witt are optimizing production. To do this, they take into account various aspects of the process, post-processing and powder handling. "We want to make the powder available for sintering with constant quality," says scientist Lars Meyer. He is conducting research into additive manufacturing in the plastics sector. "If products are to be mass-produced to a high standard of quality and resources are to be used efficiently at the same time, this is the best basis".
POLYLINE is the abbreviation for Integrated Line Application of polymer-based AM technologies. The project is coordinated by the company EOS, which offers technologies in industrial 3D printing of metals and plastics.
Further information:
Institute of Mechanical and Process Engineering, Chair of Production Engineering:
Prof. Dr. Gerd Witt, Tel. 0203/37 9-3360, gerd.witt@uni-due.de,
Lars Meyer, phone 0203/37 9-3241, lars.meyer@uni-due.deEditor: Alexandra Nießen, Tel. 0203/37 9-1487, alexandra.niessen@uni-due.de
- EU Project on Corona Vaccine
16th March 2020,
Antiviral Agents and New Test Models.
Illustration of SARS-CoV-2The novel coronavirus (SARS-CoV-2) has already claimed several thousand lives worldwide. A specific therapy or vaccination is not yet available. In an EU project, researchers led by Professors Jan Münch from University of Ulm and Thomas Schrader from the University of Duisburg-Essen (UDE) hope to accelerate the development of an effective antiviral therapy. In cooperation with other European partners, the researchers hope to quickly and efficiently test different potential active substances against the coronavirus. The consortium has acquired 2.8 million euros for the two-year "Fight nCoV" project, which is led by Stockholm University.
As with other pathogens, the penetration of the coronavirus into the host cell is considered a promising target for antiviral drugs. This process is inhibited by three substances that are being investigated and optimized for their effectiveness against SARS-CoV-2 in the "Fight nCoV" project. One of these substances is the molecular tweezers developed by Thomas Schrader and Jan Münch: These bind to the viral envelope and destroy the pathogen. In addition, a single-stranded oligonucleotide and macromolecular inhibitors, which prevent the interaction of the pathogen with the target cell, will be investigated.
To test the efficacy and safety of these agents, the research group uses various models. In the Ulm laboratory, the researchers hope to determine the antiviral effectiveness of the substances using harmless viral pseudotypes. The most promising substances will subsequently be tested by European partners for the inhibition of SARS-CoV-2 in cell cultures. Animal models up to primates will be used for further investigations in order to start clinical studies in the near future. "We are facing the urgent task of finding an effective therapy against SARS-CoV-2. Therefore, we are making the test models available to other European research groups as soon as possible," emphasize virologist Münch and chemist Schrader.
The novel coronavirus is a zoonosis: the pathogen has spread from animals to humans. If the antiviral substances actually prove effective against SARS-CoV-2, they might possibly be used in future zoonoses or other viral respiratory diseases.
"Fight nCoV" is funded by the EU through the HORIZON 2020 project. In addition to the Universities of Stockholm (Sweden), Ulm, Duisburg-Essen, and Aarhus (Denmark), the research institutions CEA (France) and Adlego Biomedical (Sweden) are involved.
Further information:
Prof. Dr. Jan Münch, Institute for Molecular Virology, University Hospital Ulm: Tel.: 0731 500-65154, jan.muench@uni-ulm.de
Prof. Dr. Thomas Schrader, Institute for Organic Chemistry, University of Duisburg-Essen: Phone: 0201 183-3081, thomas.schrader@uni-due.de
Editor: Annika Bingmann
- Kondo Screening Cloud
12th March 2020,
Expansion of Quantum Physical Phenomenon Measured for the First Time.
Arne Ludwig (left) and Andreas Wieck are experts in the high-precision production of semiconductor samples.
© RUB, MarquardFor 50 years, the physical effect that among other things underlies superconductivity at high temperatures, had eluded size measurements.
An international research team has for the first time determined the size of the so-called Kondo Screening Cloud. The quantum-physical phenomenon describes an interaction of conducting electrons with impurities in the material, which causes a reduction in electrical resistance. Prof. Andreas Wieck and Dr. Arne Ludwig from the Chair of Solid State Physics at Ruhr-Universität Bochum (RUB) were involved in the publication in the scientific journal Nature, online on March 11, 2020. The Japanese Riken Center was in charge of the work, other partners came from Hong Kong, Korea and Tokyo.
Electrons behave like a crowd
Electric current is a flow of negatively charged electrons attracted by a positively charged pole. "Analogously, you can imagine a crowd of people walking towards a shop with a discount offer," compares Andreas Wieck. "If masts of street signs are in their way, the pedestrians have to swerve or are stopped - this means that fewer people are moving towards the shop at the same time". This is also the case with electrons that encounter impurities in the material. This increases the resistance and reduces the current flow.
The following happens with the Kondo effect, transferred to the pedestrian example: Pedestrians near the obstructing masts form a cluster around the obstacle and shield it - with the result that other pedestrians no longer even notice the presence of the masts, but can walk past them freely. Similarly, electrons can form a cloud around a contaminant in the material and mask it - this is a screening cloud. In reality, however, the Kondo effect is more complicated and temperature-dependent.
Experimental measurements fit with theoretical predictions
Over the past 50 years there have been many attempts to determine the extent of the Kondo Screening Cloud. Previous simplified experiments had determined values in the nanometer range, but theoretical calculations predicted a size in the micrometer range. The new experiments described in the Nature article now confirm the theoretical predictions.
Editor: Julia Weiler - CENIDE Conference 2020
6th March 2020,
Scientific Exchange with Dom view.
Participants of the CENIDE Conference 2020 © CENIDEThe CENIDE Conference 2020, which took place again in the Kardinal-Schulte-Haus in Bergisch-Gladbach from March 2 to 4, 2020, was well-attended: About 100 participants - a good mixture of working group leaders and young scientists - informed themselves about research in other areas of the CENIDE network, exchanged views and discussed. Seven prizes for the best lectures and posters were also awarded.
The basic requirements for a successful conference were given: A professionally organized and well-equipped location, beautiful surroundings with a view of the entire city of Cologne, good food. Accordingly, the mood was good during the 47 scientific lectures, two poster sessions and the discussion on the overall CENIDE strategy within the individual working groups.
For the best posters, the jury, consisting of Dr. Andrea Hoyer, Prof. Doris Segets and Prof. Heiko Wende, awarded a total of four prizes of equal value, in alphabetical order:
- Gereon Behrendt: Malachite- and LDH-based Catalyst Precursors for Methanol Synthesis from CO2-rich Synthesis Gas
- Lukas Engelke: Coarsening and Shrinkage: A Grain Scale Model
- Daniela Karolin Wey: Electrophoretic Deposition of Calcium Phosphate Nanoparticles as Genetically Active Coating for Cochlear Implants
- Benjamin Zingsem: Biologically Encoded Magnonics
The jury of the Short Talk Award included Prof. Stephan Schulz (substitute for Prof. Malte Behrens), Prof. Marika Schleberger and Prof. Kadijeh Mohri. The winners of the prizes with equal value are in alphabetical order:
- Malte Jongmanns: How Non-equilibrium Phonon Excitations Keep a Lattice Cool
- Anna Rabe: Synthesis of Cobalt Iron Oxide Catalysts via Co-precipitation of Crystalline Precursors
- Sebastian Tigges: One-step Synthesis of Carbon-supported Electrocatalysts
All winners will receive a prize money of 100 euros.
The next CENIDE conference is planned for spring 2022. With a bit of luck, the magnolias in the inner courtyard will already be in bloom this time.
Editor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Bathen Re-elected as chairman
5th March 2020,
ProcessNet division "Adsorption".
Prof. Dieter Bathen © Johannes-Rau-ForschungsgemeinschaftProf. Dieter Bathen, holder of the Chair of Thermal Process Engineering at the University of Duisburg-Essen (UDE) and scientific director of the affiliated Institute for Energy and Environmental Technology (IUTA), has been re-elected for the third time as chairman of the ProcessNet division "Adsorption". Bathen has been head of the group, in which around 200 experts from process engineering, plant construction, metrology and technical chemistry are organized, since 2010 and has now been confirmed in office for another five years.
ProcessNet is a joint organisation of VDI (Association of German Engineers) and DECHEMA (Society for Chemical Engineering and Biotechnology). The Adsorption Division evaluates and initiates research projects and organizes the professional exchange between industry and university research.
Adsorption is a widely used separation process, which is applied, for example, in extractor hoods, gas masks, water treatment plants or in natural gas purification to remove disturbing impurities or toxins from gases or liquids. Porous solids such as activated carbons or silica gels with extremely large internal surfaces are used.
- UA Ruhr Project Finalist in Clusters 4 Future Competition
27th February 2020,
New Materials for Green Technologies.
Scanning electron microscope image of a highly active and long-term stable catalyst material that is produced in a single step (process patented in 2019) The carbon walls, which are only a few nanometres thick, can be seen.
© UDETo develop new materials and technologies for a sustainable energy supply in the Rhine-Ruhr region - and then bring them quickly to market: This is the goal of a future cluster, supported by players from the University Alliance Ruhr (UA Ruhr). The project is among the finalists in the competition of the Federal Ministry of Research, competing for a funding of up to €5 million per year for a maximum of nine years.
Coordinators of the project are University of Duisburg-Essen (UDE), Ruhr-Universität Bochum (RUB) and the Hydrogen and Fuel Cell Technology Centre (ZBT). In the "Clusters 4 Future" initiative of the Federal Ministry of Research, it is among the 16 finalists from 137 submitted concepts nationwide.
Looking beyond the horizon is the declared goal of WISDOM4E, short for „Wissensbasiertes Design komplexer Materialien und Systeme für nachhaltige elektrochemische Energiespeicherung und -wandlung" (Knowledge-based design of complex materials and systems for sustainable electrochemical energy storage and conversion): "Up to now, promising developments of functional materials for energy conversion and storage have mostly been considered individually," explains Professor Christof Schulz (UDE). "In contrast, we want to link up research fields and also bring industry, politics and society on board. By considering the legal and political framework from the outset, a product is brought to market faster.
"For example, we have jointly developed a patent on novel materials that are now to be rapidly turned into highly active catalysts and battery components. We can only meet the challenge of identifying the best from the infinite number of possible material combinations with new methods," adds Professor Alfred Ludwig (RUB).
Further players from the region welcome
Three lines of development are being pursued within WISDOM4E: To be able to use hydrogen as a green energy source in the future, sustainable and efficient catalyst materials on an industrial scale are required. The recycling of CO2 also involves catalysts and electrodes: if carbon dioxide is converted into valuable substances such as aviation fuel and basic chemicals immediately after it is produced, the greenhouse gas does not escape into the atmosphere - a win-win situation. The third aspect on the agenda is new materials and electrodes for high-performance batteries.
At the beginning of 2021, it will be clear whether WISDOM4E will be funded as one of probably seven future clusters. "The initiative is already working with many partners from science and industry," emphasizes Professor Angelika Heinzel (ZBT). "We want to actively involve other players, especially start-ups, small and medium-sized enterprises, in order to get the scientific results into industrial implementation.
Further information:
UDE: Prof. Christof Schulz, Faculty of Engineering, Tel. 0203/37 9-8161, christof.schulz@uni-due.de
RUB: Prof. Wolfgang Schuhmann, Faculty of Chemistry and Biochemistry, Tel. 0234/322 6200, wolfgang.schuhmann@rub.de
ZBT: Prof. Angelika Heinzel, Centre for Fuel Cell Technology GmbH, Tel. 0203/7598 4225, a.heinzel@zbt.de - Easy Application of Catalysts
14th February 2020,
Publication in Angewandte Chemie International .
RUB's catalyst team in the laboratory
© RUB, KramerElectrocatalysts can help to obtain chemicals from renewable raw materials or to use alternative energy sources. Researchers at Ruhr-Universität Bochum (RUB) and the University of Duisburg-Essen (UDE) have developed a new method of applying catalyst particles to tiny electrodes.
The method is inexpensive, simple and quick to implement. In order to characterize catalysts and test their potential for various applications, researchers have to fix the particles on electrodes so that they can then be examined using transmission electron microscopy, for example.
The scientists around Prof. Wolfgang Schuhmann from RUB describe their results in the journal Angewandte Chemie International, published online on January 20, 2020. Professor Dr. Corina Andronescu is involved from the UDE side.
Wafer-thin electrodes
In transmission electron microscopy (TEM), a thin electron beam is sent through the sample to observe the electrochemical processes taking place at an electrode. In order for the beam to penetrate the structures, all sample components must be very thin. The diameter of the electrode to which the catalyst is applied is therefore only ten micrometers wide.
Applying catalyst particles drop by drop
With earlier methods, the catalyst particles were either distributed evenly throughout the sample, i.e. even where they were not needed, or methods were used that could damage the material. Both disadvantages are eliminated with the new method, which is based on electrochemical scanning cell microscopy. The researchers fill a glass capillary with a liquid containing the catalyst particles. They then approach the capillary to the electrode onto which the particles are to be deposited. A tiny drop of the particle liquid hangs at the lower opening of the capillary.
The researchers approach the capillary to the electrode until the drop of liquid comes into contact with the electrode and closes an electrical circuit. This automatically stops the approach, preventing damage to the material. The scientists then retract the capillary, but the drop of liquid remains on the electrode. This step can be repeated as often as required. Finally, the researchers evaporate the solvent so that only the catalyst particles remain, which are now fixed to the electrode.
Suitable for many catalyst materials
"Once the methodology is established, it offers a clean, easy-to-use and variable way of applying and measuring a large number of different catalyst materials stably and reproducibly on liquid cell TEM chips," explains Schuhmann.
The work is funded by the Deutsche Forschungsgemeinschaft (DFG) and the European Research Council.
Original Publication:Tsvetan Tarnev, Steffen Cychy, Corina Andronescu, Martin Muhler, Wolfgang Schuhmann, Yen-Ting Chen: A universal nano-capillary based method of catalyst immobilization for liquid cell transmission electron microscopy, 2020, in: Angewandte Chemie International Edition, DOI: 10.1002/anie.201916419
Further information:Prof. Dr. Wolfgang Schuhmann, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Tel. +49 234 32 26200, wolfgang.schuhmann@rub.de
Editor: Dr. Julia Weiler
- Tong Li Appointed Professor at Ruhr-Universität Bochum
13th February 2020,
Characterization of High-performance Materials on the Atomic Scale.
Newly appointed Professor Tong Li. © Michael SchwettmannTong Li wants to make catalyst development more efficient. In addition to catalyst materials, aerospace materials are also in the focus of the researcher, who accepted a professorship in February 2020.
In order to develop high-performance catalysts, not only good production processes are required, but equally good methods to characterize the potential catalysts. The latter is the main research interest of Tong Li, who already worked on this topic as a junior professor at Ruhr-Unviersität Bochum (RUB). Since February 7, 2020, she has been a professor for the characterization of high-performance materials on an atomic scale.
In addition to catalysts, the researcher is also interested in materials used in aviation, such as titanium alloys. Here, too, she deals with the characterization of the materials.
Expert in atomic probe tomography Tong Li is an expert in atom probe tomography. Using this method in combination with transmission electron microscopy, it can make the structure of materials visible atom by atom. She collaborates with various colleagues in chemistry to research how the process can help make catalysts better.
Materials Chain congratulates Tong Li on her new professorship!
Editor: Julia Weiler E-Mail: julia.weiler@uv.rub.de
- MERCUR Continues
13th February 2020,
Further 22 Million Euro Funding For UA Ruhr Network.
Ion Accelerator
© UDE/Frank Preuß
The Mercator Research Center Ruhr (MERCUR), founded ten years ago by the Mercator Foundation and the universities of the University Alliance Ruhr (UA Ruhr), will receive a further 22 million euros for the next five years. This will further expand the successful cooperation between TU Dortmund University, Ruhr-Universität Bochum and University of Duisburg-Essen through funding programmes. The Mercator Foundation is supporting the activities of MERCUR with 11 million euros. The universities will provide the co-financing.In the last 10 years, MERCUR has supported numerous projects of the association with about 48 million euros. The Center has contributed to the fact that UA Ruhr is now a model for regional and inter-university cooperation beyond the borders of the Ruhr Area which has become more attractive as a science location.
In the future, MERCUR will provide more effective support for joint research projects and thus increase performance. The aim is to make the Ruhr Area even more visible nationally and internationally as an excellent research location and thus strengthen the region as a whole.
Pioneering university network
"With new formats, we want to promote the development of joint research priorities in the UA Ruhr, support scientists in the acquisition of third-party funded joint projects and promote joint ventures in other areas of the universities," says MERCUR Managing Director Dr. Gunter Friedrich.
"UA Ruhr is regarded nationwide as a pioneer of university networks. With our continued support for MERCUR, we want to further expand the networking of the universities, increase their scientific performance and thus strengthen the Ruhr region as a whole", explains Dr. Wolfgang Rohe, Managing Director of the Mercator Foundation.
"UA Ruhr faces up to the national and international competition for the latest scientific findings and technological innovations in a variety of ways and is at the same time an important motor for the social and economic development of the region. This success story must be continued with the support of MERCUR," said UDE Rector Prof. Dr. Ulrich Radtke, representing the rectorates of the three universities.
Further information and editorial office:
Isabell Hilpert, MERCUR, Tel. 0201-61696511, isabell.hilpert@mercur-research.de - WISNA Professorships Announced
12th February 2020,
Faculty of Chemistry Seeks Reinforcement.
Key topics for the announced WISNA Professorships
© UDEWithin the Federal and State Programme for the Promotion of Young Scientists, the Faculty of Chemistry at the University of Duisburg-Essen (UDE) has announced two junior professorships with tenure track. Applications are accepted until March 9, 2020.
"Structural Analysis of Inorganic Materials" and "Nanomaterials in Aquatic Systems" are the areas to be filled. Both positions are initially established as junior professorships and are linked to W2 with a tenure track.
For the "Structural Analysis of Inorganic Materials", an expert (m/f/x) with special knowledge in solid state analysis and/or new theoretical methods of structure elucidation is sought. A focus on inorganic functional materials is desired.
Applicants (m/f/x) for "Nanomaterials in Aquatic Systems" should have special knowledge in the field of analysis, behaviour, application and/or ecotoxicological effects of synthesised inorganic nanomaterials or their composites in aqueous systems. A strong expertise in analytical methods for detection, characterisation and quantification of nanomaterials in the presence of a natural background matrix is desirable.
To the job advertisements: Structural analysis of inorganic materials
Further information:Prof. Dr. Torsten C. Schmidt, Dean of the Faculty of Chemistry, dekanat@chemie.uni-due.de.
Nanomaterials in aquatic systemsEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Ammonia as a Sustainable Energy Source
5th February 2020,
Climate and Environmentally Friendly Technology.
Ammonia cracker © UDE/ZBTA little water, some nitrogen from the air, and electricity from the wind farm: ammonia is made up of readily available raw materials, and it is understood as a green energy source. Highly efficiently, hydrogen can be produced from ammonia to generate usable energy. Scientists at the University of Duisburg-Essen (UDE) and the Zentrum für BrennstoffzellenTechnik GmbH (ZBT) are developing an innovative plant for this purpose: the ammonia cracker.
NH3toH2, in words "ammonia to hydrogen", is the name of the project, which will run until 2022 and will culminate in a cracker that is as efficient as possible and can be coupled directly with a fuel cell. It is being developed in the ZBT laboratory, with support from scientists from the UDE "Energy Technology" chair. The researchers are using simulation models as well as investigations on real prototypes. Ideally, at the end of the project, a system will be created whose components such as reactor, burner, heat exchanger and insulation are optimally matched to each other. At the heart of the technology is the catalyst, for which the most suitable candidate is to be found in the coming years.
Energy supply without CO2
Ammonia is promising for a sustainable, carbon-free energy supply: It can be produced from readily available, inexpensive elements - in the future with energy from environmentally friendly sources. Electricity could be used for this purpose, which comes from natural resources, but can still be stored only insufficiently from large photovoltaic systems or wind farms. If required, liquid ammonia can be broken down into its constituent parts hydrogen and nitrogen again with the help of the cracker. A fuel cell converts the gas produced in this way into electrical energy, and the only exhaust gases formed are water, nitrogen and oxygen.
Such ammonia-supplied fuel cell systems can, for example, replace climate-damaging diesel units in developing and emerging countries where there is no reliable electrical grid. The advantage over direct use of hydrogen is that ammonia has a high energy density, is easy to transport and uncomplicated to store. NH3 thus offers enormous potential for reducing greenhouse gas emissions.
The project is funded by the Europäischen Fonds für regionale Entwicklung (EFRE).
Further Information:
Florian Nigbur, Energietechnik, Tel. 0203/37 9-2109, florian.nigbur@uni-due.de
Michael Steffen, ZBT, Tel. 0203/7598-3033, m.steffen@zbt.deEditor: Birte Vierjahn, Tel. 0203 37 9-2427, birte.vierjahn@uni-due.de
- Fast Screening for Potential New Catalysts
4th February 2020,
Electrochemistry.
The successful team: Michael Meischein, Tobias Löffler, Wolfgang Schuhmann, Alan Savan and Alfred Ludwig (from the left) © RUB, MarquardA new concept makes it possible to identify the most promising among an abundance of possible element combinations.
The success of energy transition depends significantly on efficient electrocatalysts, for instance for fuel cells or the reduction of CO2. Special alloys made from five or more elements are promising candidates. A team of researchers from Ruhr-Universität Bochum (RUB) has developed a concept in order to quickly screen an abundance of possible element combinations to identify which are worth optimising. It helps to directly ascertain the potential of a possible alloy. The team reports in the journal Angewandte Chemie International Edition on 22 December 2019.
Efficient catalysts made from inexpensive and available elements
The researchers’ hopes with regard to new catalysts made from inexpensive and available elements rest on what are known as complex solid solutions, also called high-entropy alloys. They consist of five or more elements that are homogeneously mixed and the diverse, complex interactions of which enable fine adjustments of the relevant properties. Importantly, it is not only the properties of the individual elements that are crucial but above all their interaction. “This opens up a wide range of otherwise unachievable possibilities in order to simultaneously optimise price and performance for possible applications,” says Professor Wolfgang Schuhmann from the Center for Electrochemical Sciences at RUB.
However, fundamental knowledge about the recently discovered new catalyst class is still lacking. What information could be provided by measurements in order to make targeted advances in catalyst development? How does this help find the right one among the almost infinite possible combinations? What effect does replacing an element have on the properties?
Interpreting results more accurately
“We have developed a concept that enables us to understand the correlations between the selection of elements, theoretical, activity-defining properties, and actually measurable parameters,” reports Tobias Löffler, doctoral candidate in electrochemistry. As the complex solid solutions differ from conventional electrocatalysts in all these points, this understanding is fundamental for experimental progress.
The researchers are thus faced with the challenge that not only the combination of elements but also the proportion of each element is crucial and any deviations change the properties. “We show how experiments with an alloy made from, for instance, five equal parts of each element can be interpreted in order to identify the element combination as potentially active,” explains Tobias Löffler. The researchers are thus able to identify quickly whether it is worthwhile optimising the proportions of the elements. “This enables us to reduce the screening workload for possible material compositions to a fraction without overlooking promising candidates,” explains Wolfgang Schuhmann. Without this knowledge, it is possible that combinations could be filtered out using conventional evaluations even though these could be highly interesting if the element ratios were optimised. “What’s more, this concept forms a cornerstone in understanding the complex mode of action of this material class, which helps to better understand the possible parameters that can be adjusted and thus derive promising design concepts from this.”
Encouraging researchers
The researchers tested these conceptual considerations with selected alloys using the oxygen reduction reaction relevant to fuel cells. They were able to demonstrate in which cases replacing or adding an element to an existing element combination has a positive effect and vice versa. They were also able to identify combinations that are suitable for further optimisation.
“For material synthesis, this means an immense saving in time and money,” says Professor Alfred Ludwig, Chair for Materials Discovery and Interfaces at RUB. “Producing and analysing all of the possible element ratios of an alloy consisting of five elements is a huge challenge. By eliminating elementary hurdles, we hope to further facilitate access to this highly topical and technological relevant field and encourage more researchers to contribute with their respective skills.”
Funding The work was funded by the German Federal Ministry of Education and Research in the project Nemezu (03SF0497B) and the German Research Foundation in the cluster of excellence Ruhr Explores Solvation Resolv EXC 2033 – project number 390677874 and the projects LU1175/23-1, LU1175/22-1 and LU1175/26-1. Support was also provided by the Fund from the Chemicals Industry and the Max Planck Research School for Interface Controlled Materials for Energy Conversion IMPRS Surmat.
Original publication Tobias Löffler, Alan Savan, Hajo Meyer, Michael Meischein, Valerie Strotkötter, Alfred Ludwig, Wolfgang Schuhmann: Design of complex solid solution electrocatalysts by correlating configuration, adsorption energy distribution patterns and activity curves, in: Angewandte Chemie International Edition, 2019, DOI: 10.1002/ange.201914666
Press contact Prof. Dr. Wolfgang Schuhmann
Analytical Chemistry – Center for Electrochemical Sciences (CES)
Faculty of Chemistry and Biochemistry
Ruhr-Universität Bochum
Germany
Phone: +49 234 32 26200
Email: wolfgang.schuhmann@rub.deProf. Dr. Alfred Ludwig
Materials Discovery and Interfaces
Institute for Material
Faculty of Mechanical Engineering
Ruhr-Universität Bochum
Germany
Phone: +49 234 32 27492
Email: alfred.ludwig@rub.de - TU Dortmund University Researchers Efficiently Generate Light with Magnetic Nanoplates
31st January 2020,
Publication in Nature Nanotechnology.
Electron microscopic image of nanoplates. Their effective thickness is only about two billionths of a metre; in the plane they are ten times as large.© Experimentelle Physik 2/TU DortmundNanoplates are chemical systems that emit light and can be used in light-emitting diodes, for example. Together with international colleagues, researchers at TU Dortmund University have succeeded in turning the platelets into strong magnets, allowing the properties of the light emitted by the nanoplatelets to be controlled in a targeted manner. The team published the results in the renowned journal Nature Nanotechnology at the end of January.
In recent years, a new class of chemically relatively easily synthesizable systems has been produced - nanoplates. These are very flat structures that are only a few billionths of a metre thick, but have a much greater extent in the plane. As a result, electrical current can flow almost unhindered in the plane, but not at all vertically.
The special feature of such structures is that they emit very bright light when such a current is injected, which is why they are planned to be used in light-emitting diodes in the future. In addition, the nanoplates can be manufactured very energy-efficiently from environmentally friendly materials. Even the color of the emitted light can be varied by choosing the thickness of the platelets and the material from which they are made.
However, little research has been done so far on the influence the surface of the nanoplates has on the light. A research group led by Prof. Dmitri Yakovlev from the Department of Experimental Physics 2 at the TU Dortmund University, together with colleagues from Russia, France, Belgium and Italy, has now succeeded in making nanoplates - which are actually non-magnetic - into strong magnets. For this purpose, they have used surfaces on which chemically unbound charges are located. This magnetism makes it possible to selectively adjust various properties of the light emitted from the nanoplates - including the speed at which the light is emitted and the polarization, i.e. the direction in which the light wave oscillates. In the production of the nanoplates, the surfaces must then be tailored accordingly.
Contact for further information:
Prof. Dr. Dmitri Yakovlev
Phone: +49 231 755 3534
fax: +49 231 755 3674
e-mail: dmitri.yakovlev@tu-dortmund.deExperimental Physics II
physics department - From 2D crystal to 1D wire
30th January 2020,
Unexpected behaviour of the material.
Careful polishing produces even steps with a height of exactly one atom – as in the attempt to build a slanted plane using only Lego bricks of the same size. © UDENo volume, not even a surface: a one-dimensional material is like a wire and has properties that are completely different to its 3D counterpart. Physicists at the University of Duisburg-Essen (UDE) have now discovered a system that, at warmer temperatures, forms self-organized wires consisting of only one row of individual atoms.
"Low-dimensional systems are en vogue", according to Professor Michael Horn-von Hoegen, experimental physicist in the UDE Collaborative Research Centre 1242 "Non-equilibrium dynamics of condensed matter in the time domain". Restricting a system of three dimensions to just one dimension creates the possibility of discovering new properties in the material.
Therefore, the scientists used stepped surfaces to allow atomic wires to form in a self-organized way by cutting a silicon crystal at an angle of 12 degrees. Careful polishing produces even steps with a height of exactly one atom – as in the attempt to build a slanted plane using only Lego bricks of the same size. The edges of the steps are formed by silicon atoms, with two rows of gold atoms deposited behind them.
Atoms shift
The researchers are now interested in every third silicon atom in this row at the edge, because it has special properties: At very low temperatures, these atoms are arranged in a regular lattice (viewed across the steps), i.e., in a two-dimensional crystal structure. And now heat is added: from previously -223°C, the system is now heated to around -123°C. This thermal energy causes the regular distances between the special silicon atoms to break up. They are now sometimes two, sometimes four atoms apart.
This way, independent chains of atoms are formed, which run along the edges of the steps. The fact that physicists can explain this phenomenon in detail today is due in large part to UDE theorist Prof. Björn Sothmann: His calculations explained what the pure experiment could not reveal.
"Here, something new emerges almost out of nowhere," Horn-von Hoegen summarises. And the result also contradicts previous expectations: "2D order at low temperatures, one-dimensional structures when it gets warmer; you don't get this kind of thing from any other material. Now we want to find out whether this also applies to other systems - maybe even at room temperature".
The highly respected scientific journal Physical Review Letters covers this in its current issue.
Original publication:
B. Hafke, C. Brand, T. Witte, B. Sothmann, M. Horn-von Hoegen, S. C. Erwin:
“Thermally Induced Crossover from 2D to 1D Behavior in an Array of Atomic Wires: Silicon Dangling-Bond Solitons in Si(553)-Au”
Phys. Rev. Lett. 124, 016102 (2020)
https://doi.org/10.1103/PhysRevLett.124.016102Further information:
Prof. Dr. Michael Horn-von Hoegen, Fakultät für Physik, +49 203 37 9-1438, horn-von-hoegen@uni-due.de
Editor: Birte Vierjahn, +49 203 37 9-8176, birte.vierjahn@uni-due.de
- Dr. Guannan Liu's Flaming Research
30th January 2020,
Humboldt Fellow visiting chair of Prof. Christof Schulz.
Dr. Guannan Liu © privatNanoparticles are the number one topic of conversation in many areas of the engineering and natural sciences. Humboldt Fellow Dr. Guannan Liu is investigating their formation in flame synthesis. She is currently a guest of Prof. Christof Schulz at the Institute of Combustion and Gas Dynamics at University of Duisburg-Essen.
In the next two years, the thermophysical engineer will focus on the so-called flame synthesis. This allows the small particles to be produced from gaseous substances in a single step. To do this, she measures the electromagnetic waves emitted by the particles as they are created. "My results can then be used to analyze and optimize the theorists' process simulations," says the 27-year-old from Nanjing University of Science and Technology, describing her project.
Liu's theoretical results could become attractive for applied research. "Flame synthesis makes it possible to produce particles with specific properties and is also easily scalable. It therefore offers potential for industrial production," says the scientist.
Compared to existing large-scale gas phase processes, spray flame synthesis offers access to a wealth of materials that cannot be produced by other processes. However, actual industrial application has so far failed because expensive starting materials have to be used and research still knows too little about the underlying processes.
Further information:
Dr. Guannan Liu, guannan.liu@uni-due.de
Prof. Dr. Christof Schulz, Tel. 0203/37 98161, christof.schulz@uni-due.deEditor: Alexandra Nießen, Tel. 0203/37 91487, alexandra.niessen@uni-due.de
- Dr. Marion Franke appointed to IHK committee
30th January 2020,
Niederrheinische Industrie- und Handelskammer.
© IHK NiederrheinThe Niederrheinische Industrie- und Handelskammer (IHK) has unanimously appointed Materials Chain Coordinator Dr. Marion Franke to the Committee for Research, Innovation and Digitisation.
"For me, working on the committee is simply part of a vivid knowledge and technology transfer. I am therefore very much looking forward to it and hope that it will contribute to the positive development of the region and strengthen the necessary link between science and industry" Franke said.
The Niederrheinische Industrie- und Handelskammer represents the overall economic interests of its member companies vis-à-vis the state government, local authorities, courts and the public. An important part of its work is to create better location conditions for companies in Duisburg and in the districts of Wesel and Kleve.
Editor: Sarah Heuser, sarah.heuser@uni-due.de
- Materials Chain - The Movie
29th January 2020,
A Glance Behind the Lab Doors.
© Materials ChainSelf-healing plastics, magnetic cooling, shape memory alloys - these are the new characteristics of the transformed Ruhr area. The region is establishing itself across the board in research on modern materials: 273 scientists from the three major universities and their working groups work together in the Materials Chain: A short movie now presents the huge research network.
Scientists from Ruhr-Universität Bochum (RUB), Technical University Dortmund (TU Do) and the University of Duisburg-Essen (UDE) are researching modern materials with new or improved properties in the Materials Chain.
In the future, for example, our fridges will no longer work with compression refrigeration but will cool magnetically - much more efficiently and without harmful components. Other research teams are working on shape memory alloys: Materials which, after deformation, "remember" their old shape and regain their original form by themselves. They are already being used in applications ranging from dentistry to space technology. The development of processors made of special bacteria mixed with nanometer-sized magnetic spheres is another area in which researchers in the Materials Chain are working. These should be able to process significantly more data than their silicon-based counterparts at the same size.
The film allows a look behind the laboratory doors of the natural scientists and engineers in the region.
Watch the movie here on our website or directly on our YouTube channel
Further information: Alexander Heinemann, 0203 / 37 9-8175, alexander.heinemann@uni-due.deEditor: Birte Vierjahn, 0203 / 37 9-8176, birte.vierjahn@uni-due.de
- Best Teacher Award for Prof. Monika Schleberger
28th January 2020,
Award from the NanoEngineering Course .
Prof. Marika Schleberger is awarded the best Teacher Award in January 2020. © UDE
On January 25, Prof. Marika Schleberger from the Faculty of Physics of University of Duisburg-Essen (UDE) was honored with the Best Teacher Award of the NanoEngineering course of study.The certificate was handed over during the graduation ceremony of the Faculty of Engineering at UDE. Schleberger has repeatedly given the lecture "Properties and Applications of Nanomaterials II" for future nano-engineers in the Nanoengineering course.
Congratulations on this very special award!
- Prof. Christof Schulz Appointed to DFG Senate Committee
21st January 2020,
Materials Chain researcher will support DFG for 3 years.
© CAR/Jan SchürmannStarting in July 2020, Prof. Christof Schulz will accompany and review the Collaborative Research Centres in the DFG Senate Committee. He was appointed to the committee for three years by the Senate of the German Research Foundation (DFG - Deutsche Forschungsgemeinschaft).
It consists of up to 40 scientists, who are also members of the Grants Committee for the Promotion of Collaborative Research Centres.
Schulz, Professor for Reactive Fluids at the Faculty of Engineering at the University of Duisburg-Essen (UDE), conducts research in the field of combustion processes and nanomaterial synthesis. Since 2007, the Leibniz Prize winner has been a member of the board of the Center for Nanointegration (CENIDE) and since 2008 director of the NanoEnergieTechnikZentrum (NETZ) at UDE.
Further information:
https://www.dfg.de/dfg_profil/gremien/senat/sonderforschungsbereiche/index.html
https://www.uni-due.de/ivg/rf/christof_schulz.php - Immunotherapy through Nano Tools
8th January 2020,
Materials Chain researchers successfully applied for funding from German Cancer Aid.
© UDE/UK Essenfrom left: Prof. Sebastian Schlücker, Prof. Barbara Saccà und Prof. Sven Brandau
Together, scientists from medicine, biology and chemistry at the University of Duisburg-Essen (UDE) are now pursuing a new and visionary approach to combating oncological diseases. In the joint project headed by Prof. Sven Brandau, nano-tools are to be developed that switch off cancer-promoting immune cells within tumours. Deutsche Krebshilfe is funding the precision immunotherapy project with 800,000 euros over three years.
With almost 230,000 deaths per year, cancer is the second most frequent cause of death in Germany according to the Federal Statistical Office. Not all cancers are the same, as there are many different oncological diseases. However, almost all human tumours have in common that their tissue contains not only cancer cells but also tumour-promoting immune cells. And this is exactly where the scientists are starting: Their goal is to specifically recognize and eliminate these immune cells through highly specific immunotherapy. To this end, they want to develop suitable molecular nano-tools in a collaborative effort.
The research groups of Prof. Sven Brandau, Faculty of Medicine, Prof. Barbara Saccà, Faculty of Biology, and Prof. Sebastian Schlücker, Faculty of Chemistry, have successfully applied for research funding from German Cancer Aid. Their project "Precision immunotherapy through molecular recognition motifs on gold nanorods" was selected from numerous project proposals and will be funded for three years from 2020 onwards with approximately 800,000 euros in the funding priority "Visionary new concepts in cancer research". The interdisciplinary team combines its know-how in immunoncology, DNA nanotechnology, nanomaterial chemistry and optical spectroscopy.
Further information:
Prof. Sven Brandau, Experimental and Translational Research, Clinic for ENT Medicine, Tel. 0201/72 3-3193, sven.brandau@uk-essen.deEditor: Christine Harrell, Tel. 0201/72 3-1615, christine.harrell@uni-due.de
- The Effect of the Hot Electron
19th December 2019,
Understanding Metal Insulator Materials .
Electron diffraction pattern of the sample (colours added later)
© Bovensiepen
You can't really see them, but you can still follow the flow of energy like in a flip book: Physicists from the University of Duisburg-Essen (UDE) have investigated the energy transfer in a metal insulator material and published their results in the journal "Physical Review B". In the long term, they could contribute to solving the heat problem in microelectronics through targeted materials design.Laptops and servers - they would be condemned to heat death without energy-consuming and bulky technology to cool the sensitive circuits. Unwanted but previously unavoidable waste heat is an expensive problem. If one traces its cause back to the atomic level, one ends up with the electron which makes its way through various materials. But how exactly?
UDE physicists from the Collaborative Research Centre "Non-equilibrium dynamics of condensed matter in the time domain" have investigated this. To do this, they used an excitation-interrogation method to investigate a material that alternately consists of thin layers of metal (iron) and insulator (magnesium oxide): a laser pulse injects energy into the system, and a short time later an X-ray beam reads out a snapshot of how it propagates through the material in the form of "hot electrons". "If we increase the temporal distance between the two pulses evenly, we can follow the process like in a film," explains experimental physicist Dr. Andrea Eschenlohr.
Reaction in a trillionth of a second
The result: in less than a picosecond (0.000 000 000 001 s), the hot electrons excite the metal lattice; almost simultaneously, the interface between the materials begins to oscillate. Another picosecond later, the insulator also reacts. "The latter surprised us," says Eschenlohr. "We did not expect that these interface oscillations are so important." Theoretical simulations confirmed the results in detail.
In the next step, the physicists now want to investigate more complex systems and generalise the results as far as possible. "In the long term, this could possibly lead to a precisely matched mix of materials for different tasks and solving the problem of waste heat.
The publication was made in cooperation with the research groups of Prof. Uwe Bovensiepen, Prof. Rossitza Pentcheva and Prof. Heiko Wende.
Original publication:
N. Rothenbach, M. E. Gruner, K. Ollefs, C. Schmitz-Antoniak, S. Salamon, P. Zhou, R. Li, M. Mo, S. Park, X. Shen, S. Weathersby, J. Yang, X. J. Wang, R. Pentcheva, H. Wende, U. Bovensiepen, K. Sokolowski-Tinten, and A. Eschenlohr
Microscopic nonequilibrium energy transfer dynamics in a photoexcited metal/insulator heterostructure
Phys. Rev. B 100, 174301 (2019) DOI: 10.1103/PhysRevB.100.174301
Further information:
Dr. Andrea Eschenlohr, phone 0203 37 9-4531, andrea.eschenlohr@uni-due.de - Bochum Team Wins Second Place with Machine Learning
19th December 2019,
Materials Science.
© RUB/MarquardActually, the algorithm was used for something else. Its use in competition showed its adaptability.
With their algorithm for predicting material properties, Dr. Yury Lysogorskiy and Dr. Thomas Hammerschmidt from the Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) at Ruhr-Universität Bochum (RUB) took second place in an international competition on machine learning. The secret of their success was the combination of data analysis with physical models and information on the chemical properties of the elements that make up potential materials for solar cells and touch screens. The algorithm from Bochum as well as the first-placed solution from Yokohama, Japan, and the third-placed solution from London, Great Britain, were published in the journal NPJ Computational Materials on November 18, 2019.
Predicting the crystal structure of materials
The methods used were actually developed to simulate metallic alloys. For the competition, the researchers adapted these methods to predict the structural stability and optical properties of transparent electron conductors. "These materials, which are for example used in touchscreens, are composed of the elements aluminum, gallium, indium and oxygen," explains Thomas Hammerschmidt. By varying the proportions, the material properties can be optimized for technological applications.
Testing the basic suitability
In this competition, which was organized by the European centre of excellence "Nomad" and the Internet platform for machine learning "Kaggle", a data set of results from quantum mechanical calculations was made available. A second data set was initially kept secret. The algorithms were to be trained with the first data set in order to then predict the second data set as accurately as possible. "This competition was about the performance and comparability of different approaches to solving problems," says Thomas Hammerschmidt.
The approach proves to be transferable
"There are different approaches for specific predictions of certain compositions," explains the researcher. "We were interested to see how transferable our own approach is to different classes of materials and tasks." The Bochum approach incorporated results of the preliminary work at ICAMS, in particular physically motivated descriptors of the local atomic environments of atoms in the crystal lattice.
Original publication
Christopher Sutton, Luca M. Ghiringhelli, Takenori Yamamoto, Yury Lysogorskiy, Lars Blumenthal, Thomas Hammerschmidt, Jacek R. Golebiowski, Xiangyue Liu, Angelo Ziletti, Matthias Scheffler: Crowd-sourcing materials-science challenges with the NOMAD 2018 Kaggle competition, in: NPJ Computational Materials, 2019, DOI: 10.1038/s41524-019-0239-3
Press contact
Dr. Thomas Hammerschmidt
Interdisciplinary Centre for Advanced Materials Simulation
Ruhr University Bochum
Phone: +49 234 32 29375
e-mail: thomas.hammerschmidt@rub.de - From Dust Particle to Planet
12th December 2019,
Mystery of Collision Barrier Solved.
© Eso/ALMAPlanets form in the rotating gas and dust cloud around a young star. Dust particles collide there and grow into huge boulders. Until now, it was unclear how this works. If the particles are a millimeter or more in size, they bounce off each other. Physicists from the University of Duisburg-Essen (UDE) seem to have solved the mystery. In experiments, they have shown that the colliding dust grains become electrically charged and therefore adhere to each other. Nature Physics reports on these findings in its current issue.
"Flour sticks to the wall, sand doesn't," explains astrophysicist Prof. Gerhard Wurm in an everyday context, explaining how the collision barrier of particles must be imagined. This "bouncing barrier" in the formation of planets has been driving science for decades. "It is undisputed that the dust grains that collide in the protoplanetary disk can never grow directly into aggregates larger than one millimeter. Nevertheless, in millions of years, this could become a planet 10,000 km in size. How does that work?"
The UDE physicists' idea: Electric charge could give adhesion. Because the dust aggregates collide again and again, they charge each other in different ways and then attract each other.
"We have systematically investigated whether this is actually possible in many experiments in the drop tower in Bremen. We represented the particle cloud with millimeter-sized glass spheres and then let the spheres collide with each other," says Wurm. "It was as we suspected: They charged positively and negatively and at low speeds they grew by several centimeters."
However, the eight-member team did not want to rely on the experiments alone. So Prof. Dietrich Wolf's research group (theoretical physics) checked the whole thing by simulations. After almost two years of research, the UDE physicists are now certain: Proof has been provided - electric charge overcomes the collision barrier! "We are certain that we have closed a gap in planet formation," Prof. Wurm is convinced. "However, many questions are still open, such as how large the aggregates can ultimately become or what role the mineral composition and the different temperatures in the gas and dust disks play in this process."
Electrical charging overcomes the bouncing barrier in planet formation', Nature Physics, veröffentlicht am 09.12.2019, DOI: 10.1038/s41567-019-0728-9
Further Information:
Prof. Dr. Gerhard Wurm, Experimentelle Astrophysik, Tel. 0203/37 9-1641, gerhard.wurm@uni-due.deEditor: Ulrike Bohnsack, Tel.0203/37 9-2429, ulrike.bohnsack@uni-due.de
- Sensor Sticker Monitors Food Production
11th December 2019,
Project Launch.
From left to right: Prof. Tschulik, Dr. Vöpel, Prof. Plumeré © RUB/KramerCompanies can easily monitor online whether everything is running smoothly in production - by sticking smart sensor stickers on machines.
Germs in the sausage factory - a horror scenario for manufacturers and consumers. In order to detect such and other disturbances of production processes in agriculture and the food industry at an early stage, researchers are developing smart sensor stickers in the "Smart (Bio)-sensors for the process industry" project, "Saber Print" for short. They can be fitted with various sensors and allow production processes to be monitored online. The project consortium includes the Cluster of Excellence "Ruhr Explores Solvation (Resolv)" at Ruhr-Universität Bochum (RUB), the University of Maastricht, the seal manufacturer Garlock from Neuss and the company Yookr from Venlo. The project is funded with a total of 1.3 million euros in the Interreg programme of the European Union.
Stickers measure substance concentration, pH value, impurities
The central innovation of the project is a flexible sensor sticker that can be directly integrated into seals, for example, to monitor industrial processes online. "Initially, we will develop sensor stickers for monitoring selected parameters, such as the concentration of certain substances like glucose, the pH value or microbial contamination," explains project coordinator Prof. Nicolas Plumeré (RUB). Part of the concept is that the stickers, which each measure certain values, can be easily replaced. "The user can attach the stickers to different industrial components, depending on the process he or she wants to monitor exactly," says Dr. Tobias Vöpel from the Centre for Electrochemistry at RUB.
German-Dutch border region benefits
With this idea, the project consortium wants to make a contribution to the digitalization of manufacturing processes - generally discussed as Industry 4.0. The continuous monitoring of industrial processes by smart machines makes production processes more efficient and sustainable. The project results will have a major impact on agriculture and the food industry, two sectors that play an important role in the German-Dutch border region. "Thanks to Saber Print, the border region can profit from this technical progress at an early stage," emphasizes Prof. Kristina Tschulik, head of RUB's Electrochemistry and Nanoscale Materials group. As the smart technology reduces installation and maintenance costs and increases overall productivity, it also expects an economic benefit for the user's operations.
Press contactProf. Dr. Nicolas Plumeré
Research Group Molecular Nanostructures
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 29434
e-mail: nicolas.plumere@rub.deProf. Dr. Kristina Tschulik
Chair of Analytical Chemistry II
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: +49 234 32 29433
e-mail: nanoec@rub.deDr. Tobias Vöpel
Center for Electrochemistry
Ruhr University Bochum
Phone: +49 234 32 29092
e-mail: tobias.voepel@rub.de - Wende New Liaison Lecturer
3rd December 2019,
Studienstiftung des deutschen Volkes.
Prof. Heiko Wende from the University of Duisburg-Essen (UDE) is now a liaison lecturer for Studienstiftung des deutschen Volkes. In October, he was officially appointed by the Foundation's Executive Board. The second liaison lecturer on the Duisburg campus also comes from the Materials Chain.
Each liaison lecturer supervises an interdisciplinary group of up to 15 scholarship holders sponsored by Studienstiftung des deutschen Volkes. Wende advises the scholarship holders on general questions concerning their studies. He is currently looking after ten students from very different fields: from politics and economics to medical technology and sociology.
Once a semester, Wende, himself an alumnus of the funding program, meets with his group for a jointly planned venture. He focuses on the interdisciplinary component of the scholarship. He wants to motivate the students to exchange ideas and to look beyond their own discipline. The regular meetings of the group offer an excellent opportunity for this. "I can broaden my horizons at these meetings", explains Wende. "Getting to know other interests and subject areas is the most exciting part of it."
Currently, two members of the Materials Chain are appointed as liaison lecturers at the Duisburg campus of the UDE: Besides Wende, head of the working group "Magnetic Nanostructures" in physics, Prof. Dr. Roland Schmechel, head of the working group "Nanostructure Technology" from the engineering sciences, is also there for the scholarship holders. Wende took over from Prof. Dr. Marika Schleberger.
Studienstiftung des deutschen Volkes is the oldest and largest scholarship organisation for gifted students in Germany. It supports students who perform excellently in their studies and are also socially committed.
Further information:
Prof. Dr. Heiko Wende, Tel. 0203 37 9-2838, heiko.wende@uni-due.deEditor: Jan Jerig
- Extending STEM Views
2nd December 2019,
120,000 Euros for zdi Student Laboratory.
© UDE, eventfrotograf.inTechnical devices such as microscopes are essential for STEM subjects. In the zdi Student Laboratory at the University of Duisburg-Essen (UDE) young people will soon be able to experience how they work, using virtual augmented reality apps. The project is financed with 120,000 euros, half of which comes from the European Regional Development Fund, the other half from the zdi Student Laboratory and the Chair for Verteilte Systeme of Prof. Dr. Torben Weis.
By using the camera and a shutter release of mobile devices, Augmented Reality (AR) apps complement the real world with digital and virtual elements. Currently the best-known examples of this technique can be seen in the gameplay of the mobile game “Pokémon Go” and in football broadcasting, where the correct free kick distance is shown on the screen. AR is now also used in industrial manufacturing and logistics, where employees receive information via data glasses or displays from mobile devices.
But AR is also useful in training. "Students retain content they have experienced much better than what they just heard", says Dr. Kirsten Dunkhorst, head of the zdi Student Laboratory at UDE. Digital images, 3D elements and videos are more vivid than texts for abstract and complex content. Professor Weis and his team are developing apps for the project "AR-InGo - Augmented Reality für die Ingenieurwissenschaften" until 2022. In the future, 8- to 13-graders will be able to virtually understand how microscopes reproduce surfaces or which chemical reactions take place in a dye solar cell.
The aim of the AR project is to develop a digital training concept and at the same time involve small and medium-sized companies. This would enable the young people already in the zdi Student Laboratory to see what their professional future could look like. "AR applications are increasingly being used as a learning tool, especially in STEM training courses or during studies", says Kirsten Dunkhorst. "If the young people already learn from us how AR is used in the engineering sciences, they may want to do so in the future and decide to study engineering."
Further information:
https://www.zdi-portal.de/efre-zdi/
https://www.uni-due.de/nano-schuelerlabor/
Dr. Kirsten Dunkhorst, zdi student laboratory, 0203/37-93409 or 98030, kirsten.dunkhorst@uni-due.deEditor: Alexandra Niessen, 0203/37-91487, alexandra.niessen@uni-due.de
- New Shape Memory Alloy Developed at RUB
29th November 2019,
Young Researchers Combine Theory and Experiment.
© RUB, MarquardA research team from Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) and the Institute for Materials (IFM) at Ruhr-Universität Bochum (RUB) developed a new shape memory alloy that returns to its original form for many times when heated. Using computer simulation, Alberto Ferrari (ICAMS) calculated a design proposal for a shape memory alloy that remains efficient for a long time even at high temperatures. Alexander Paulsen (IFM) produced it and confirmed the prediction experimentally. The alloy of titanium, tantalum and scandium is not only a new high-temperature memory alloy. The research team has also shown how theoretical predictions can be used to produce new materials more quickly. The group published an article in Physical Review Materials on October 21, 2019, and their work was highlighted as Editor's suggestion.
Avoiding unwanted phases
Shape memory alloys can regain their original shape after deformation when the temperature changes. This deformation is based on a transformation of the crystal lattice in which the atoms of the metals are arranged. The researchers speak of a phase transformation. "In addition to the desired phases, there are also phases that persist and considerably weaken or even completely destroy the shape memory effect", explains Dr. Jan Frenzel from the Institute of Materials. The so-called omega phase occurs at a certain temperature, which depends on the composition of the material. Many previous shape memory alloys for the high-temperature range were able to withstand only a few deformations before they became unusable due to the formation of the omega phase.
Promising shape memory alloys for high temperature applications are based on a mixture of titanium and tantalum. By changing the proportions of these metals in the alloy, researchers can influence the temperature at which the omega phase occurs. "While it is possible to push this temperature up, one thereby lowers the temperature of the desired phase transformation", says Jan Frenzel.
Additive changes the properties
The researchers at RUB wanted to understand the mechanisms of the onset of the omega phase in detail and thus find ways to improve the performance of shape memory alloys for the high-temperature range. Alberto Ferrari, PhD student at ICAMS, calculated the stability of the respective phases as a function of temperature for different compositions of titanium and tantalum. "He was thus able to confirm the results of experiments", reports Dr. Jutta Rogal (ICAMS).
In the next step, Ferrari simulated the admixture of small amounts of third elements into the shape memory alloy of titanium and tantalum. He selected the candidates according to certain criteria, for example they should be as non-toxic as possible. The result was that an admixture of a few percent of scandium would have to result in the alloy functioning for a long time even at high temperatures. "Scandium belongs to the rare earths and is correspondingly expensive. But since we only need very little of it, it's still worth the effort", explains Jan Frenzel.
Prediction is accurate
Alexander Paulsen then produced the alloy calculated by Alberto Ferrari at the Institute for Materials and tested its properties in an experiment: the results confirmed the calculations. A microscopic examination of the samples later proved that even after many deformations, no omega phase was found in the crystal lattice of the alloy. "We have thus not only expanded our basic knowledge of titanium-based shape memory alloys and developed possible new high-temperature shape memory alloys," says Jan Frenzel. "It is also excellent that the predictions of the computer simulation are so accurate. Since the production of such alloys is very time-consuming, the implementation of computer-aided design proposals for new materials promises much faster success.
Original publication
Alberto Ferrari, Alexander Paulsen, Dennis Langenkämper, David Piorunek, Christoph Somsen, Jan Frenzel, Jutta Rogal, Gunther Eggeler, Ralf Drautz: Discovery of ω-free high-temperature Ti-Ta-X shape memory alloys from first-principles calculations, in: Physical Review Materials 2019, DOI: 10.1103/PhysRevMaterials.3.103605Press contact
Dr. Jutta Rogal
Atomistic simulation of the kinetics of phase transformations
Interdisciplinary Centre for Advanced Materials Simulation
Ruhr University Bochum
Phone: +49 234 32 29317
E-mail: jutta.rogal@rub.deDr. Jan Frenzel
Chair of Materials Science
Institute for Materials
Faculty of Mechanical Engineering
Ruhr University Bochum
Phone: +49 234 32 22547
E-mail: jan.frenzel@rub.de - Bioelectrocatalysis as Basis for the Energy Revolution
28th November 2019,
Chemistry.
© RUB, MarquardBiocatalysts are promising materials for the switch to renewable energies. But what works in the laboratory does not necessarily mean a breakthrough for industrial applications: a research team from the Center for Electrochemical Sciences (CES) at Ruhr Universität Bochum (RUB) discusses hurdles that have to be overcome in the journal Nature Catalysis from 25 November 2019, focusing on two main research fields: the development of bioelectrodes for hydrogen oxidation for biofuel cells and the development of efficient biophotoelectrodes for the solar-assisted synthesis of chemicals and regenerative fuels.
Enzymes as catalystsThe effectiveness and selectivity of biological catalysts have been continuously optimised by nature over millions of years. Redox proteins are a special class of these enzymes, as they catalyse not only purely chemical reactions but also reactions coupled to an electron transfer. “In this respect, the analogy to reactions such as those used in industrial electrocatalytic processes such as hydrogen oxidation or oxygen reduction on precious metals in fuel cells is of great importance,” says Professor Wolfgang Schuhmann from the Center for Electrochemical Sciences at RUB. Another essential class are light-activated enzymes that are activated by light irradiation and can generate an electron flow, in the same way as semiconducting materials. A key factor is that such enzymes contain active centres which, in contrast to catalysts based on precious metals and purely inorganic semiconductor materials, are made up of elements that are abundantly present in nature.
Only a few applications to dateBecause of these properties, such biological systems constitute promising model compounds or even alternatives for future catalyst and semiconductor technologies. “However, to date only a few specific electrocatalytic applications have been implemented by bioelectrocatalytic methods,” says Wolfgang Schuhmann. The properties of the enzymes themselves and the use of special and complex electrode architectures, which are necessary for the development of powerful and thus competitive processes, curtail such processes.
In the review article, the RUB team discusses the limitations and hurdles to be overcome for the technological use of hydrogenase-based bioelectrodes for hydrogen oxidation and efficient biophotoelectrodes based on protein complexes from photosynthesis, photosystem I and II, as well as bacterial photoactive centres.
Enzymes immobilise and protectThe essential aspect for the structure and design of bioelectrodes is the electrical connection of enzymes to the electrode surface. The authors describe how specifically synthesised redox polymers not only immobilise and electrically wire the enzymes, but also protect them from harmful substances such as oxygen.
In addition, the team outlines approaches that facilitate deployment in processes on a large scale. “Here, we are paying particular attention to the potential of synthetic enzymes, which are regarded as a major step towards potential applications,” says Dr. Adrian Ruff from the project team. Technological approaches such as the introduction of special electrode materials, the use of gas diffusion electrodes to increase mass transport, or special immobilisation methods such as the directed binding of photoactive enzymes using the Langmuir-Blodgett technique are also discussed.
Editor: Meike Drießen
- Nano Platinum for Neurological Implants
27th November 2019,
Mercator Fellow Brian Giera at University of Duisburg-Essen. Read original article
© privatNormal movements without trembling or cramping - this is what brain pacemakers allow people with Parkinson's disease to do. High quality and long-term stability of the implanted electrodes are essential in order to minimize follow-up operations. To this end, researchers at the University of Duisburg-Essen (UDE) want to coat the implants with metal nanoparticles and thus improve the contact between implant and tissue. Dr. Brian Giera from the Livermore National Laboratory (USA), currently a Mercator Fellow at the UDE, is also involved.
In the project "Coating neuroelectrodes with nanoparticles by electrophoretic deposition", which is funded by the German Research Foundation, scientists from Technical Chemistry I are collaborating with colleagues from Hannover Medical School.
Improving the implant
A great deal revolves around electrophoretic deposition (EPD): the tiny wires of the electrodes - less than 1 mm in diameter - are immersed in a liquid containing platinum nanoparticles. If an electric field is then applied, the particles settle very thinly on the surface of the electrodes and improve contact with the brain tissue: the electrical resistance of the implant decreases, the current reaches the nerve cells better, the battery lasts longer and thus fewer follow-up operations are necessary.
For people with restrictive movement disorders, deep brain stimulation improves their quality of life considerably. This is particularly true in serious cases where medication is no longer effective. In order to further improve the EPD and thus the quality of the coating, knowledge from various disciplines is now being brought together.
Dr. Brian Giera at the UDE again
The researchers are working with Dr. Brian Giera from the Californian Lawrence Livermore National Laboratory, who will be at the UDE for a second time for a month starting November 28. The 34-year-old is one of the world's leading experts in the field of computer-aided simulation of these processes.
Together, Giera and the UDE researchers want to understand the EPD in detail: For example, how does the arrangement of the particles on the electrode surface change if their initial concentration is changed? What influence does the strength of the applied electric field have? "If we know these relationships, we can control the process specifically," explains Dr. Christoph Rehbock, head of the Nano-Bio-Materials research group within Technical Chemistry. "We can then use the type of coating to adjust the resistance of the electrodes.
"I am delighted to be involved in such an interdisciplinary and international cooperation project in which experts from physics, chemistry and medicine work closely together," says Giera.
Further information:
Dr. Christoph Rehbock, Technical Chemistry I, University of Duisburg-Essen, Tel. 0201 18 3-3040, christoph.rehbock@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Third Funding Phase for CRC 103
25th November 2019,
Superalloys for Turbine Blades. Read original article
© RUB, MarquardTurbine blades operate at more than 1,000 degrees Celsius. And they should do so for as long as possible to save fuel.
To ensure that turbines in aircraft and gas power plants live as long as possible and work efficiently, the team at Collaborative Research Center 103 "From atoms to turbine blades - scientific basis for a new generation of single-crystal superalloys" is optimizing the microstructure of the turbine material. The German Research Foundation (DFG) has now approved the third and final funding phase of the Collaborative Research Centre/Transregio (SFB/TRR) at Ruhr Universität Bochum (RUB) until 2023. Following the development of the fundamentals over the past eight years, the focus is now on manufacturing processes.
Optimising the microstructure
The SFB/TRR 103, in which RUB and the Friedrich-Alexander-University of Erlangen-Nuremberg are involved, deals with a new generation of monocrystalline superalloys from which blades for turbines are made. These have to withstand mechanical stress and chemical attack at extremely high temperatures. "Their chemical composition and microstructure must be optimised in order to achieve higher efficiencies," says Professor Gunther Eggeler, spokesperson of the SFB/TRR and professor of materials science at RUB. Today, the main focus is on the efficient use of resources: One of the goals is to reduce fuel consumption and extend the service life of components.
Closer to the application
In the first two funding phases, the SFB/TRR 103 team developed basic principles for the production of alloys, alloying concepts, cross-scale modelling, mechanical testing and microstructural characterisation. In the third funding phase, which is now beginning, the researchers want to apply and further develop these results. "In the second funding phase, we took a major step towards the application of methods and towards greater complexity," said Eggeler. "For the basic projects, this means considering even more complex alloy compositions; for the materials engineering projects, it means approaching actual manufacturing processes.
Editor: Meike Drießen
Contact:
Prof. Dr. Gunther Eggeler
Chair of Materials Science
Faculty of Mechanical Engineering
Ruhr University Bochum
Phone: 0234 32 23022
E-mail: gunther.eggeler@rub.de - New Magnets for Future Energy Technologies
25th November 2019,
CRC 270 .
© TU DarmstadtState-of-the-art functional materials, such as strong permanent magnets for use in wind turbines and electric motors, or magnetic materials for efficient cooling, are needed to transition to a low emissions future. The German Science Foundation (DFG) has therefore granted €12 million for a new Collaborative Research Center (CRC) called “HoMMage”. This centre will begin its first 4 years on 1st of January 2020 at Technische Universität Darmstadt and the University of Duisburg-Essen (UDE).
Strong permanent magnets based on rare earth elements are a requirement for future mobility and sustainable electricity generation. Wind turbines, which are expected to contribute more electricity with every passing year, and electric cars, which need to be both energy and resource-efficient, both rely on strong permanent magnets. A permanent magnet with an increased efficiency of 2 % can increase the range of a car by 20 km. Changing the temperature of a material by the application of an external magnetic field is the principle behind the magnetocaloric effect. This principle will enable operating refrigerators and air-conditioning devices quietly, with low energy consumption and without the use of traditional refrigerants, themselves strong greenhouse gases.
Requirements: Affordable, environmentally friendly and efficient.
All of these technologies rely on efficient magnet materials as their key components. However, they often contain raw materials which are rare, toxic and expensive. The researchers of the new CRC 270 HoMMage, which stands for “Hysteresis Design of Magnetic Materials for Efficient Energy Conversion”, are searching for new materials which operate close to their physical limits and are made from earth abundant materials.
Together with their colleagues from Max-Planck-Institut für Eisenforschung (MPIE) and Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons at Jülich Research Centre, the scientists of both universities will develop new processing methods for innovative magnet materials. Materials scientists, physicists, chemists and process engineers will work on magnetic materials by manipulating individual atoms but also by deforming massive samples. By linking the experimental and theoretical groups together in one centre they will be able to continuously cross-link their developments. Artificial intelligence, which accelerates materials discovery and the rapid identification of the most promising material combinations, will also be employed in HoMMage.
Understanding the smallest detail
“We want to gain a detailed understanding of what is happening within the material, or in other words, identify the DNA of the magnet”, explains CRC 270-speaker Oliver Gutfleisch, Professor of Functional Materials at TU Darmstadt.” That includes how the structural, magnetic and electronic interactions look like at the atomic level up all the way to the 2 kg of magnets that are placed in the electric motor of a car.” This knowledge will enable adjusting the local and global properties of a magnetic material by additive manufacturing and severe plastic deformation methods. “To achieve this goal, we have developed new ideas for processing techniques on all length scales, so that we can place the precious elements in the bulk magnet only where really needed”, co-speaker Professor Michael Farle from UDE adds.
The activities of CRC 270 HoMMage are embedded in two profile areas “From Material to Product Innovation” and “Future Energy Systems” at TU Darmstadt as well as in the key research area “Nanoscience” of UDE.
Further information:
Professor Oliver Gutfleisch (speaker), Material Science (TU Darmstadt), 06151 16-22140, oliver.gutfleisch@tu-darmstadt.de
Professor Michael Farle (co-speaker), Physics (Universität Duisburg-Essen), 0203 37 9-2075, michael.farle@uni-due.deEditors:
Dr.-Ing. Sonja Laubach, TU Darmstadt, 06151 16-22153, laubach@fm.tu-darmstadt.de
Birte Vierjahn, Universität Duisburg-Essen, 0203 37 9-8176, birte.vierjahn@uni-due.de - 1.5 Million Euros for Test Centre
18th November 2019,
Inland Waterway Vessels - Autonomous and Emission-free.
© JRF e.V./Alex Muchnik
From left:
Prof. Dirk Abel (RWTH Aachen), Prof. Dieter Schramm, Dean of Engineering Sciences (UDE), Hendrik Schulte (NRW Ministry of Transport), DST Director and UDE Professor Bettar Ould el Moctar, Dieter Bathen (UDE and JRF) and Ocke Hamann (Lower Rhine Chamber of Industry and Commerce).Autonomous inland waterway vessels with electric propulsion would be good for the climate. But a lot still needs to be programmed and tested. The Development Center for Ship Technology and Transport Systems (DST), a University of Duisburg-Essen (UDE) associated institute in Duisburg, is therefore setting up a test and management center. Dr. Hendrik Schulte, State Secretary at the NRW Ministry of Transport, was happy to announce funding of 1.5 million euros for the test centre.
DST will set up the centre, called VELABI, in cooperation with the engineering departments of UDE and RWTH Aachen University. Eight scientists will develop and test new processes there for more than 10 years. With the largest inland port in Europe, Duisburg offers the best conditions for testing autonomous ships under real conditions. Until then, however, conventional and autonomous vehicles will have to share the waterways. Similar to the air traffic controllers in a tower,, skippers based in the management centre will therefore first ensure that there are no misunderstandings or collisions.
The funding decision was presented at an event of the Johannes Rau Research Association (JRF), which dealt with the question "Green & Smart Shipping in NRW - When will the autonomous, emission-free inland waterway vessel arrive?"
- TU Researchers Bring Light into Darkness
13th November 2019,
International Team Presents Results in Nature Communications.
© TU DortmundMicroscopic image of a nano antenna consisting of two cylinders with a radius of half a micrometer each and a height of 200 nanometers. The two cylinders are less than 100 billionths of a meter apart. The emission of light is particularly strong in this area. To generate light, the antenna is coated with a thin layer of tungsten diselenide, which has a thickness of only one atomic layer
The interaction of light and matter is decisive for our lives. Examples are photosynthesis in nature or photovoltaics for solar cells. This is why intensive efforts are being made worldwide to optimize the interaction of light and matter. Researchers at the TU Dortmund are playing a major role in this. This week they presented the results of their research together with an international team in the renowned journal Nature Communications.
Optimising the interaction of light and matter is particularly successful when the light field can be concentrated and amplified in small spatial areas, e.g. in so-called nanoresonators or nanoantennas. These are structures with two cylinders, each with a radius of half a micrometer and a height of 200 nanometers. They are shaped in such a way that they form a small gap with dimensions down to a few billionths of a meter in which the light field is trapped.
In the last decade, it became possible to manufacture such resonators with high precision from metals. Although the light field is amplified in small, specifically shaped gaps in the metal, at the same time it is strongly attenuated in the metal itself, similar to the electrical resistance during current transport in metals. The resulting losses represent a considerable limitation for practical applications.
Increased interaction due to gallium phosphide antennas
A team from Sheffield, London, Munich and TU Dortmund has now succeeded in constructing such antennas from a material - gallium phosphide - in which these losses are completely suppressed. The increased light-matter interaction could be demonstrated by introducing a light source, a monatomic layer of tungsten diselenide, into the antenna. The researchers were able to show that the light emission from this material increases considerably compared to emission without an antenna.
The Dortmund team contributed to the investigations with time-resolved measurements and showed that the light emission is drastically accelerated and that electrical energy can thus be converted into light particularly efficiently. These experiments were part of a new collaboration between Sheffield and Dortmund, which will receive £1.4 million over the next four years from the British Research Council Engineering and Physical Sciences Research Council (EPSRC).
Further information:
Sortino et al., Enhanced light-matter interaction in an atomically thin semiconductor coupled with dielectric nano-antennas, Nature Communications volume 10, 5119 (2019)
Contact person for further questions:
Prof. Dr. Manfred BayerPhone: +49 231 755 3532
fax: +49 231 755 3674
E-mail: manfred.bayer@tu-dortmund.deExperimental Physics II
Faculty of Physics - Sparkasse Duisburg Awards Prizes
12th November 2019,
Young Scientists Honoured.
© Sparkassen DuisburgIn the picture (from left):
Dr. Julia Schmälter, Dr. Maximilian Büscher, Nele Harnack, Markus Heckschen, Dr. Christian Schneider, Rector Prof. Ulrich Radtke, Amelie Pullen, Dr. Joachim Bonn (Chairman of the Board of Management of Sparkasse Duisburg).The Sparkasse Duisburg has now honoured four students and four doctoral students* for their outstanding achievements. Two of them are members of working groups in our Materials Chain. The prizes are endowed with 2,000 and 1,000 euros respectively.
They were honoured for their outstanding dissertations, which were awarded summa cum laude:
- Dr. Maximilian Büscher, Topic: "Influence of voluntary reporting on the cost of capital of mandatory convertible bonds against the background of imperfect competitive conditions - Empirical evidence for AT1 CoCo bonds of European banks" (Business Administration)
- Dr. Julia Schmälter, Topic: "The EU Complaince Deficite: Unwilling or Incapable?" (Social Sciences)
- Dr. Dario Düsterloh, Topic: "Function optimization and complexity control in the development process of mechatronic chassis systems using the example of electromechanical steering systems" (Engineering Sciences)
- Dr. Christian Schneider, Topic: "Wordline instantons and the Sauter-Schwinger effect" (Physics)
Awards were given for special academic achievements:
- Amelie Pullen (Business Administration)
- Alessia Zaffaroni (Social Sciences)
- Nele Harnack (Engineering Sciences)
- Markus Heckschen (Physics)
Further information:
Johannes Hümbs, Sparkasse Duisburg, Tel. 0203/2815-836011, pr@spk-du.deEditor: Ulrike Eichweber, webredaktion@uni-due.de
- Alexander von Humboldt Research Fellowship
7th November 2019,
Nano Building Blocks for Medicine.
© Alexander von Humboldt-Stiftung/Michael JordanDr. Chin Ken Wong is a fellow of the Alexander von Humboldt Foundation (AvH). Since October, he has been supported by the Foundation's Postdoctoral Fellowship. The chemist has been a research assistant at the Gröschel Working Group since October. He is researching the development of artificial building blocks for the transport of substances in the body.
His current research project, which deals with "Preparation of biodegradable block copolymer hexosomes for controlled release applications", will be supported by the AvH Foundation for the next two years.
Block polymers are tiny artificial building blocks that arrange themselves independently into certain structures. Wong's research focuses on a special form of these polymers called hexosomes. His goal is to develop biodegradable variants that could, for example, distribute drugs in the body.
Wong received his doctorate in chemistry in Sydney in 2018. He then spent a year at the School of Chemistry and the ARC Training Centre for Chemical Industries, both part of the University of New South Wales. Since June 2019 he has been working at the NanoEnergieTechnikZentrum (NETZ) of the University of Duisburg-Essen.
The AvH Research Fellowship is awarded to above-average qualified scientists from abroad and enables long-term research projects in cooperation with a scientific host. The focus is on supporting postdoctoral students whose doctorates were obtained no more than four years ago. The funding can last between six and 24 months.
Further information:
Jun-Prof. André H. Gröschel, Tel. 0203 / 37 9-8212, andre.groeschel@uni-due.deEditor: Jan Jerig
- PhD Award of the Verband der Elektrotechnik
5th November 2019,
Semiconductor Quantum Dot Devices.
© PrivatOn November 20, Dr. Franziska Muckel will be honored for her outstanding dissertation. She is awarded this year's doctoral prize by the Rhine-Ruhr Electrical and Electronic Manufacturers' Association (VDE). She received her doctorate in March 2019 from the UDE in the working group of Prof. Gerd Bacher.
Muckel's dissertation was entitled "Magnetically doped semiconductor quantum dots from solvent-based production: from functionality to device". She is currently doing postdoctoral research at the University of Seattle in Washington.
Speaker at the award ceremony will be Prof. Dr. Oliver Ambacher, Director of the Fraunhofer Institute for Applied Solid State Physics in Freiburg. Muckel will present her doctoral thesis following the keynote lecture on "Quantum Metrology".
The award ceremony will take place at 16:30 in the Gerhard Mercator House on the Duisburg campus.
The VDE PhD Prize is awarded for special doctoral achievements in electrical engineering, electronics, information technology or computer science and in complementary technologies and sciences. It has been awarded annually by VDE Rhein-Ruhr since 1992.
Registrations for the participation in the award ceremony are possible by Mail until 8.11. to petra.merker@uni-due.de
Further information:
Prof. Dr. Gerd Bacher, Engineering Sciences, Tel.: 0203 379-3406, gerd.bacher@uni-due.deEditor: Jan Jerig
- How Oxygen Destroys the Heart of Important Enzymes
4th November 2019,
Biology.
© RUB, MarquardNew findings should help to protect hydrogen-producing enzymes from harmful oxygen in the future - interesting for biotechnology.
Certain enzymes, such as hydrogen-producing hydrogenases, are unstable in the presence of oxygen. Researchers at the Ruhr University Bochum (RUB) have elucidated the reasons for this at the atomic level. They report the results in the Journal of the American Chemical Society, JACS for short, published online on October 14, 2019.
Three RUB groups worked together on the experiments: Dr. Julian Esselborn - today at the University of California, San Diego -, Prof. Dr. Thomas Happe and Dr. Leonie Kertess from the Photobiotechnology working group were involved. The team cooperated with Prof. Dr. Eckhard Hofmann from the Röntgenstrukturanalyse an Proteinen research group and Dr. Ulf-Peter Apfel from the Inorganic Chemistry I department.
The interdisciplinary cooperation at the interface of biology, chemistry and physics was embedded in the Cluster of Excellence Ruhr Explores Solvation (Resolv) and the Research Training Group Microbial Substrate Conversion (Micon).
Structural changes due to oxygen
The scientists investigated a hydrogenase from the bacterium Clostridium pasteurianum. The special feature of this class of enzymes is their structure consisting of six iron and six sulphur atoms. The so-called cofactor forms the heart of the protein on which the actual hydrogen production takes place.
The researchers stored several samples of the enzyme with oxygen for different lengths of time. They then used X-ray structure analysis to investigate how the three-dimensional structure of the proteins had changed. "This method is very complex and complicated, but it helped us to follow the destructive process on an atomic level," said Julian Esselborn.
Incubation with oxygen only altered individual atoms of the enzyme, i.e. certain iron atoms of the cofactor. This gradually led to the decay of the entire active centre. By understanding which iron atoms are particularly affected, the researchers hope to be able to better protect biotechnologically interesting proteins against oxygen in the future.
Editor: Julia Weiler
Original publicationJulian Esselborn, Leonie Kertess, Ulf-Peter Apfel, Eckhard Hofmann, Thomas Happe: Loss of specific active-site iron atoms in oxygen-exposed [FeFe]-hydrogenase determined by detailed X-ray structure analyses, in: Journal of the American Chemical Society, 2019, DOI: 10.1021/jacs.9b07808
Press contact
Prof. Dr. Thomas Happe
Photobiotechnology Working Group
Faculty of Biology and Biotechnology
Ruhr University Bochum
Phone: 0234 32 27026
E-mail: thomas.happe@rub.de - Lecturer Award of the Chemical Industry Fund for Ulf-Peter Apfel
30th October 2019,
Chemistry.
© RUB, MarquardThe chemist works with teams at two institutions. This collaboration makes it possible to translate new ideas from basic research directly into applications - for example in the field of CO2 recycling.
Dr. Ulf-Peter Apfel has received the Lecturer Award of the German Chemical Industry Fund. The group leader at the Fraunhofer Institute for Environmental, Safety and Energy Technology in Oberhausen and at the Ruhr University Bochum accepted the award, which is endowed with 75,000 euros, in Ludwigshafen on October 30, 2019. The Chemical Industry Fund awards the prize to outstanding young scientists from the fields of chemistry and chemical biology who have achieved above-average achievements in teaching and outstanding scientific achievements.
Producing hydrogen and converting carbon dioxide
The production of hydrogen and the question of how carbon dioxide can be electrochemically converted into valuable raw materials for industry are the main research topics of Ulf-Peter Apfel. Together with his team, he is inventing new catalysts, electrodes and reactors for these conversion processes. Apfel is researching the basis for this with the junior research group "Activation of small molecules" at the Ruhr University. Together with the "Electrosynthesis" group at the Fraunhofer Institute, he is developing concepts for application based on these findings, also on an industrial scale.
"We bring pure chemistry and engineering together," says Ulf-Peter Apfel. "I like bringing new developments from the basics to the application. That wouldn't be possible without the cooperation of these two teams."
Editor: Julia Weiler
Press contact
Dr. Ulf-Peter Apple
Junior Research Group "Activation of Small Molecules"
Faculty of Chemistry and Biochemistry
Ruhr University Bochum
Phone: 0234 32 24187
E-mail: ulf.apfel@rub.deand
Group Electrosynthesis
Energy Division
Fraunhofer Institute for Environmental, Safety and Energy Technology
Phone: 0208 8598 1571
E-mail: ulf-peter.apfel@umsicht.fraunhofer.de - Chemistry 4.0
30th October 2019,
The Next Step: From Excellent Research to Start-ups.
© RUB, MarquardJohannes Peuling, Uta Hohn, Kristina Tschulik und Martina Havenith mit dem Entrepreneurship-Berater Peter-Christian Zinn (von links)The incubator for chemical start-ups has begun its work.
In chemistry, it is harder for founders to establish a company than in other fields. The start-up centre "Start4Chem", which has just been launched, offers help. Docked to the Ruhr Explores Solvation (Resolv) excellence cluster, it is part of the Start-up Centre NRW, for the construction of which the RUB is receiving state funding totalling more than 20 million euros.
The first lecture for students from the natural sciences took place on 28 October 2019. The series "From Top-level Research to Top-level Business" deepens various aspects of setting up a company and familiarises students and doctoral candidates with the necessary know-how and the necessary steps.
Start with 40 participants
The initiators of Start4Chem, Prof. Dr. Kristina Tschulik and Prof. Dr. Martina Havenith, opened the incubator together with Prof. Dr. Uta Hohn, Vice Rector for Planning and Structure at the RUB, and Johannes Peuling, Managing Director of the Bochum Institute of Technology. Other professors from the RUB, representatives of the NRW Ministry of Economics and the chemical industry, founders and more than 40 young scientists who have registered for the course were also guests.
"The Start4Chem start-up incubator is the first milestone towards innovative chemistry 4.0 in the region," said Hohn. Chemistry 4.0 describes a new, green chemistry that is sustainable, post-fossil and networked. Start-ups could create faster paths from excellent science to useful applications for society.
A start-up culture with role models
However, according to Havenith, there are current difficulties in setting up start-ups in the natural sciences. Unlike in information technology, a computer is not enough in chemistry. Rather, scientists need not only a good idea but above all this: subject-specific infrastructure, access to the company network, a networked campus, know-how and a new start-up culture with role models.
The idea of Start4Chem was inspired by discussions in the "From Idea to Product" forum at the Ruhr Conference, which was moderated by Havenith together with NRW Economics Minister Prof. Dr. Andreas Pinkwart. "The excellent research is established, now Resolv wants to become a nucleus for excellent foundation", says Havenith.
Socially, this step is timely.
- Kristina TschulikKristina Tschulik is responsible for the conception and further development of Start4Chem in addition to her work as head of the working group Electrochemistry and Nanoscale Materials. Her aim is to translate findings from cutting-edge research into industrial applications as quickly as possible. "Socially, this step is timely! With the new course, we want for the first time to give students from the natural sciences the opportunity to deal with entrepreneurial aspects, to awaken a spirit of entrepreneurship and to show them a third profession - that of self-employment", says Tschulik.
Editor: Jens Wylkop
- Material Impales Bacteria
29th October 2019,
Medicine/Material Research.
© Jenny ThynneLike on a nail board, bacteria are damaged on a newly developed surface with nano columns. The aim is to prevent the colonisation of implants. The model for this is nature.
Around 350,000 people in Germany are fitted with a new joint every year. Knees and hip joints are the classics. In most cases, everything goes well, but in two to five percent of all cases, an infection occurs after the operation. Often the new joint has to be removed again and intensive antibiotic therapy follows before a new implant is inserted in another operation.
Hidden behind a biofilm
Many thousands of patients have to undergo another complex operation because bacteria have been able to settle on the implant. "The germs are mainly introduced during the first operation," says Prof. Dr. Manfred Köller, head of the Department of Surgical Research at the RUB Clinic Bergmannsheil. They particularly love foreign surfaces because the body's own immune system works less well here than elsewhere. Once the germs have attached themselves, they multiply and hide behind a biofilm that neither immune cells nor antibiotics can damage so easily.
"We therefore have to prevent the germs from attaching to the implant and wanted to achieve this only by modifying the surface without using antibiotics," says Manfred Köller. In their search for strategies, the RUB researchers became aware of the results of an Australian research group that discovered in 2012 that a structure found on the wings of certain cicadas, for example Psaltoda claripennis, had antibacterial properties.
Metal imitates insect wings
The wings are covered over and over with tiny columns of wax-like material, which are only about 200 nanometres in size and cause damage to the bacterial cell wall. "Until then, it was thought that bacteria could be eliminated in nature mainly by chemical processes," explains Manfred Köller. "It has now become clear that they can also be destroyed mechanically. Of course, we were very interested in this, which is why we sought cooperation with the materials researchers at the RUB.
The coating of surfaces with nanostructures is a specialty of the Chair of Materials Discovery and Interfaces of Prof. Dr. Alfred Ludwig. Here is a so-called sputtering system with which it was possible to generate the nanocolumn structure of the cicadas almost identically from metal.
Nadine Ziegler is working here on her doctoral thesis. She uses a special sputtering process called Glancing Angle Deposition, or GLAD for short. "In this process, individual titanium atoms are released by a plasma from a disk of pure titanium and accelerated in the direction of the carrier material. They hit from the side at an angle," she explains. The atoms are deposited on the carrier; first a so-called germ is formed in some places. Fewer atoms are deposited in its slipstream. The greater the distance from the germ, the more atoms can deposit. This creates a landscape of characteristic nanocolumns of titanium atoms. "If you rotate the carrier during the coating process, you can influence the shape of these columns," says Nadine Ziegler.
Plan B for round bacteria
The researchers then colonised the surfaces coated with nanocolumns with Escherichia coli bacteria. In fact, they were able to identify many mechanically destroyed germs.
"Of course, we were enthusiastic about this at first," says Manfred Köller. "In clinical practice, however, there are other bacteria that often cause problems, particularly with implant infections, in particular staphylococci. However, they proved to be completely unimpressed by the nanocolumns and were able to multiply on the surface without being slowed down. The researchers soon realised the reasons for this: staphylococci have a much thicker and therefore more stable cell wall and, as spherical bacteria, also less contact with the surface. Therefore, they had to develop an additional weapon against this germ. It was obvious to use silver, which has long been known for its antibacterial effect. Resistances such as to common antibiotics hardly develop against silver.
The aim was to place as little silver as possible on the nanocolumns in order to preserve their structure and at the same time increase the release of the antibacterial silver ions. The researchers therefore had to make the silver corrode and release silver ions. In order to cause the desired corrosion process, the researchers had to reach into their bag of tricks. "We use the principle of a sacrificial anode," explains Manfred Köller. It is based on the fact that when two metals come into contact, the one with the lower electrochromic conductivity is used.
How to apply a sacrificial anode system to nanocolumnsThe research team therefore experimented with various precious metals in combination with silver. It turned out that combinations of silver and the platinum group elements platinum, palladium and iridium were particularly suitable for killing germs and many times more successful than pure silver.
"Now the question remained as to how such a sacrificial anode system could be applied to the nanocolumns," said Nadine Ziegler. Initially, she created a cap-like coating on the column surface. However, this led to the nano columns becoming dull and losing their mechanical antibacterial effect. "So we started sputtering on nanopatches that were a hundred times smaller," explains the researcher.
While the sputtering process for the nanocolumns takes around four hours, the application of the nanopatches takes only 20 seconds. The researcher used it to produce surfaces on which silver and platinum spots only a few nanometres in diameter and height were applied. Such so-called decorations of nanocolumns are so small that they can only be seen in the transmission electron microscope.
Tests with the finished surfaces showed that the material only develops a reliable effect against staphylococci when the platinum and silver stains are produced one after the other. "Why this is the case has not yet been clarified at the atomic level," says Manfred Köller. "We assume the formation of galvanic nanoelements."
Silver consumes itself in three days
"As the silver disappears within three days due to corrosion, we have a self-limiting system that is supposed to prevent infection in the first delicate phase after the operation," the researcher sums up. In this phase, a race for the surface takes place: Germs and the body's own cells compete for the surface of the implant. If it is covered by the body's own tissue, the risk of infection decreases even if the silver is used up.
The nanocolumns do not damage the body's own cells. On the contrary, in initial experiments it looks as if the columns stimulate certain blood cells and thus further stimulate healing. "Further investigations now have to show whether the whole thing also works under the conditions of clinical use," said Köller.
Editor: Meike Drießen
- Quantum-level Light-matter Interaction
22nd October 2019,
Physics.
Just as Schrödinger's cat is both dead and alive in a thought experiment, researchers created a superposition state that was both light and matter.
© RUB, KramerResearchers have succeeded in fusing light and matter at the quantum level. They have created a state similar to that of Schrödinger's cat in a thought experiment.
In a quantum computer, information could be stored in certain matter structures, the so-called quantum dots. In order to be able to transport the information over certain distances, for example through fiber optic cables, it must be transferred from matter to light. In the journal "Nature", researchers describe such a light-matter interface. The results were published online on 21 October 2019. Teams from the University of Basel, RUB and the Université de Lyon worked together on the project.
Quantum bits of light and matter
Quantum dots can be realized in semiconductors by, for example, locking an electron in a very limited range. The team led by Dr. Arne Ludwig and Prof. Dr. Andreas Wieck from the Bochum Chair of Solid State Physics specializes in the production of these structures. The information units in such a system are called quantum bits or qubits for short. "In addition to matter qubits, we also generated flying qubits in the form of photons in our experiment," says Arne Ludwig. The scientists coupled light and matter in such a way that information can be transferred from matter to light and back to matter.
The photon is there and not there at the same time.
- Arne Ludwig"Put simply, the photon is repeatedly absorbed and emitted by matter," describes Arne Ludwig. "In more realistic terms, however, we must speak of a superposition of states: The photon is there and not there at the same time. So we see a fusion between the states light and matter."
The states "photon there" and "photon gone" - or in other words the states light and matter - did not simply alternate in the system, but they continuously merged into each other. "It is not until we measure that we realize that the system has decided to be either light or matter," explains Arne Ludwig. "It's just like Schrödinger's cat from the somewhat abstruse thought experiment."
Editor: Julia Weiler, Phone: +49 234 32 25228; E-mail: julia.weiler@uv.rub.de
- New Project to Use CO2 as a Resource
18th October 2019,
Chemistry and Mechanical Engineering.
300 ml high-pressure reactor for electrochemical alcohol synthesis
© Fraunhofer UMSICHTAlcohols are a common raw material for the chemical industry. Researchers want to produce them from the greenhouse gas carbon dioxide in the future. In a single process step, the greenhouse gas CO2 is to be transformed into valuable raw materials for the chemical industry. This is the goal of the "Elkasyn" project, which the Federal Ministry of Economics and Energy is funding with 2 million euros from 2019 to 2022.
The RUB team includes Dr. Ulf-Peter Apfel from the Chair of Inorganic Chemistry I and Prof. Dr. Eckhard Weidner and Dr. Sabine Kareth from the Chair of Process Engineering Transport Processes. The Fraunhofer Institute Umsicht in Oberhausen coordinates the research network, which also includes Siemens AG, Mitsubishi Hitachi Power Systems Europe and the Institute for Technical Chemistry at the University of Stuttgart.
Two steps, several disadvantages
Conventional concepts for the use of CO2 as a raw material often provide for a two-stage process. In the first step, hydrogen is produced using electricity from renewable sources. In the second step, hydrogen and carbon dioxide are converted into the final product. The two-stage process has several disadvantages: On the one hand the intermediate product hydrogen has to be stored, on the other hand energy losses occur during hydrogen production by electrolysis.
Saving up to 20 percent energy
The new synthesis process is intended to eliminate these disadvantages. The project team plans to produce alcohols such as methanol, ethanol, propanol and butanol from carbon dioxide and water in a single process step - the energy for this will come from regenerative sources. The scientists expect to be able to save around 20 percent energy compared to the two-stage process.
In the Elkasyn project - short for "Increasing the Energy Efficiency of Electrocatalytic Alcohol Synthesis (elektrokatalytischen Alkoholsynthese)" - researchers are developing and investigating components for two alternative systems, one operating at normal pressure and the other at high pressure. The Bochum groups are analyzing how carbon dioxide behaves in the respective system and developing new electrodes.
Editor: Julia Weiler, +49 234 32 25228, julia.weiler@uv.rub.de
- EU Twinning Project in Cancer Therapy
14th October 2019,
Magnetically Destroying the Tumor.
"MaNaCa" is about the targeted destruction of cancer cells with magnetic nanoparticles. But at the same time, it is a mentoring program for the Academy of Sciences in Armenia: The project on two levels, in which physicists from the Center for Nanointegration (CENIDE) of the University of Duisburg-Essen (UDE) are significantly involved, is funded by the European Union with 800,000 €.
Twinning is the technical term for the EU's help in further developing technological and scientific expertise in non-European partner countries: A specific discipline or institution of the respective nation is supported by being led by at least two internationally leading European research institutions.
The project "MaNaCa - Magnetic Nanohybrids for Cancer Therapy" aims to improve the scientific potential of the Institute for Physical Research of the National Academy of Sciences in Armenia. Experienced project partners are the UDE, the Aristotle University of Thessaloniki in Greece and a consulting company from Luxembourg.
On the scientific side, for three years MaNaCa will concentrate on the application of magnetic particles in cancer therapy. Two therapeutic variants are in focus: In hyperthermia, the particles are specifically introduced into tumour tissue. Their internal magnetic field is then set into rapid oscillation by an external magnetic field. As a result, they overheat and kill the diseased cells in their environment; healthy tissue remains undamaged. An alternative is magnetic-mechanical cell death. The magnetic nanoparticles are located directly on the membrane of the tumor cell. Even tiny mechanical oscillations on an atomic scale are then sufficient to destroy the cancer cells affected. Both techniques work without surgery.
"Magnetic-based treatments are already real alternatives to radiation and chemotherapy in the laboratory," explains physicist Prof. Michael Farle, one of the UDE scientists involved. "Nevertheless, we want to enable even more targeted therapy by limiting overheating to the individual tumour cell or even to a vulnerable point in its metabolism.
The project has just started and will end in September 2022.
Further information:
Prof. Michael Farle, Experimental Physics, Tel. 0203/37 9-2075, michael.farle@uni-due.deEditor: Birte Vierjahn, Tel. 0203/37 9-2427, birte.vierjahn@uni-due.de
- Ending Tetris in logistics
11th October 2019,
Chipless Radio Labels for Imprinting.
The innovative radio tag developed by Materials Chain researchers. © UDEThe wagon is packed, once again the courier points the reader at the loading area, checking: everything on board, nothing forgotten. Printed radio labels without chips should make this possible in the future. The DruIDe* project, in which four Materials Chain members from the University of Duisburg-Essen (UDE) are playing a leading role, will not only result in a new technology, but also in two start-ups that will take care of the market launch.
Every year, billions of parcels are shipped worldwide - as individual shipments or deliveries for the retail trade. To date, each parcel has to be identified individually by its barcode: rotate it correctly, scan it, stack it sensibly in an offline version of the computer game classic Tetris.
It is much faster with a chipless label made of nanosilicon: The silicon comes in the form of nanoparticles from the NanoEnergieTechnikZentrum (NETZ) and the Institute for Energy and Environmental Technology (IUTA) at UDE. It is introduced into a special ink that can be printed directly onto the package using an inkjet printer and processed by laser into a functioning electronic circuit. "We are the first to print silicon nanoelectronics," explains Niels Benson, Professor of Printable Materials for Signal Processing Systems at UDE.
He and his colleagues Thomas Kaiser, Daniel Erni and Roland Schmechel work with five other institutions, including the University of Twente (Netherlands).
New technology saves material
The new technology not only makes life easier for logisticians and parcel carriers, it also saves a lot of material: trees. In contrast to the barcode, the RFID label ("radio-frequency identification") is reusable, and so is the parcel. Since it does not require a chip, its price is around €0.01, which is around five times cheaper than its conventional counterpart.
Prof. Thomas Kaiser knows the following about data protection: "A special reading device is required to read the label. It only works within a radius of about ten meters and only reveals that a certain ID is nearby."
Start-up: airCode
At the end of October, the six project partners from the Netherlands and Germany will present the innovation at the "RFID Tomorrow" trade fair in Darmstadt. The start-up 'airCode' has been officially working on the market launch of the technology since 8 October. "Our demonstration is still based on a few bits," says Kaiser. "We need 50 to 60 bits to differentiate between billions of objects. We are confident that we will have achieved this in five to ten years."
A new company is also being set up on the Dutch side, which will market the nano-ink.
*The DruIDe project is being implemented as part of the INTERREG programme Germany-Netherlands and is co-financed with over 3.1 million euros by the EU, the Dutch Ministry of Economic Affairs, the NRW Ministry of Economic Affairs and the State Chancellery of Lower Saxony.
Further information:
Faculty of Engineering Sciences:
Prof. Niels Benson, Tel. 0203/37 9-1058, niels.benson@uni-due.de
Prof. Thomas Kaiser, Tel. 0203/37 9-1873, thomas.kaiser@uni-due.deEditor: Birte Vierjahn, Tel. 0203/37 9-2427, birte.vierjahn@uni-due.de
- "Technological Sovereignty in a Future Field"
10th October 2019,
6th Ruhr Symposium on Functional Magnetic Materials .
Attentive listeners at the 6th Ruhr Symposium on Functional Magnetic Materials. © UDEAround 120 representatives from industry and science met on 9 October for the 6th RUHR Symposium at the Fraunhofer inHaus Centre on the UDE Duisburg campus. Functional magnetic materials were the focus of the event, at which State Secretary Oliver Wittke promoted the electric car completely "made in Germany".
Germany's "technological sovereignty in a future field" was the demand of the Parliamentary State Secretary of the Federal Ministry of Economics and Energy in his keynote speech, which opened the event. He himself spoke of an "ambitious goal". "But", Wittke continued, "we do not shy away from competition".
Germany has a lot of catching up to do when it comes to e-mobility, especially when it comes to China. Nevertheless, the participants agreed that future technologies should be sustainable - both in terms of materials and in terms of working conditions, logistics and disposal. Efficient cooling plays a decisive role here, as two of the 15 speakers, Prof. Karl Sandemann from the City University of New York and Dr. Lucas Griffith from the Department of Energy at Iowa State University (both USA), made clear in their presentations.
'Magnetism' is a far-reaching field of research. It ranges from modern cooling techniques using magnetocaloric materials, whose temperature can be changed by applying a magnetic field, to efforts in materials science to replace rare earths with classical metal compounds.
The Ruhr-Symposium is a joint event of the Center for Nanointegration (CENIDE) and the Center Automotive Research (CAR) of the University of Duisburg-Essen. At the 7th edition in autumn 2020 everything will revolve around 'catalysis'.
Further information:
Steffi Nickol, Tel. 0203 37 9-8177, steffi.nickol@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37 9-8176, birte.vierjahn@uni-due.de
- Determining the Activity of Catalyst Particles Free of Precious Metals
4th October 2019,
Chemistry.
Corina Andronescu, Tsvetan Tarnev and Harshitha Barike Ayappa discuss an experiment with the electrochemical scanning cell microscope. © RUB, KramerPrecious metal-free nanoparticles could serve as catalysts for the production of hydrogen from water. Because they are so small, their properties are difficult to determine. Materials Chain chemists have now developed a new process with which they can characterize individual precious metal-free nanoparticle catalysts.
The particles could be a cheap alternative to precious metal catalysts in order to obtain hydrogen from water by electrolysis. "In order to develop effective nanoparticles, we need to understand how the structure and activity of individual particles or small particle groups are related," says Prof. Dr. Wolfgang Schuhmann from the Center for Electrochemistry at Ruhr-University Bochum (RUB). He describes a new measurement method for this purpose with the Bochum researchers Tsvetan Tarnev and Dr. Harshitha Barike Ayappa as well as Prof. Dr. Corina Andronescu from the University of Duisburg-Essen (UDE) and other colleagues in the journal "Angewandte Chemie", published online on 26 July 2019.
So far, there are few techniques available to measure the catalytic activity of individual or fewer nanoparticles. "The currents that have to be measured are extremely small and it is necessary to find individual or a few nanoparticles and be able to measure them reproducibly," Schuhmann explains. The research team, which cooperates within the University Alliance Ruhr, showed that such analyses are also possible with high throughput - namely with electrochemical scanning cell microscopy.
New reference system developed
Until now, the method had not been used for this purpose because the nanoparticles had to be tested under demanding chemical conditions and thus large measurement inaccuracies occurred. This made a reliable interpretation of the results impossible. In their current work, the researchers developed a new reference system for electrochemical scanning cell microscopy. By cleverly using a stable internal standard, they eliminated the measurement inaccuracies and enabled long-lasting measurements under the given conditions with high throughput.
Self-made nanoparticles analyzed
The researchers produced carbon particles with nitrogen and cobalt inclusions on a plate of glassy carbon, the particles being present on the surface either individually or in groups of a few particles. In a single experiment, they were able to use scanning cell microscopy to determine the electrochemical activity of these particles or particle groups.
The particles catalyzed the so-called oxygen development reaction. The electrolysis of water produces hydrogen and oxygen - the limiting step in this process is currently the partial reaction in which the oxygen is produced; more efficient catalysts for this partial reaction would simplify the production of hydrogen.
Original publication:
Tsvetan Tarnev, Harshitha Barike Aiyappa, Alexander Botz, Thomas Erichsen, Andrzej Ernst, Corina Andronescu, Wolfgang Schuhmann: Electrochemical Scanning Cell Microscopy Investigation of Individual ZIF-Based Nanocomposite Particles as Electrocatalysts for Oxygen Development in Alkaline Media, in: Angewandte Chemie, 2019
DOI: 10.1002/ange.201908021Tsvetan Tarnev, Harshitha Barike Aiyappa, Alexander Botz, Thomas Erichsen, Andrzej Ernst, Corina Andronescu, Wolfgang Schuhmann: Scanning electrochemical cell microscopy investigation of single ZIF-derived nanocomposite particles as electrocatalysts for oxygen evolution in alkaline media, in: Angewandte Chemie International Edition, 2019
DOI: 10.1002/anie.201908021Further information:
Prof. Dr. Wolfgang Schuhmann, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Tel. 0234 32 26200, wolfgang.schuhmann@rub.deEditor: Dr. Julia Weiler, RUB
- Change in the Analysis Center
1st October 2019,
ICAN under New Management.
© F. J. Meyer zu HeringdorfProf. Frank Meyer zu Heringdorf has been the new Scientific Director of the Interdisciplinary Center for Analytics on the Nanoscale - ICAN for short - since 1 October 2019.
He replaces Prof. Axel Lorke, who has held this position for the past two years. Meyer zu Heringdorf is for many years the world's leading expert in microscopy with slow electrons (LEEM & PEEM) - the best scientific prerequisites for leading ICAN.
The Interdisciplinary Center for Analytics on the Nanoscale enables researchers from different disciplines to use equipment and methods that are too costly and time-consuming for individual research groups. This also applies to scientists from other research institutions and industry who cooperate with ICAN and can commission analyses.
We would like to thank Professor Lorke very much for his commitment in the past years and wish the new ICAN Director Professor Meyer zu Heringdorf much success and joy in his new position!
- As in Nature
27th September 2019,
Converting CO2 into Raw Materials Using Nanoparticles.
The research team: Corina Andronescu, Wolfgang Schuhmann, Patrick Wilde, J. Justin Gooding and Peter O'Mara (from left). © RUB, KramerEnzymes use cascade reactions to produce complex molecules from comparatively simple raw materials. Materials Chain researchers have copied this principle.
An international research team has used nanoparticles to convert carbon dioxide into raw materials. Scientists at Ruhr-University Bochum and the University of New South Wales in Australia have copied the principle from enzymes that produce complex molecules in multi-step reactions. The team transferred this mechanism to metallic nanoparticles, also known as nanozymes. The chemists used carbon dioxide to produce ethanol and propanol, which are common raw materials for the chemical industry.
The team led by Prof. Dr. Wolfgang Schuhmann from the Bochum Center for Electrochemistry and Prof. Dr. Corina Andronescu from the University of Duisburg-Essen, together with the Australian team led by Prof. Dr. Justin Gooding and Prof. Dr. Richard Tilley, reported in the Journal of the American Chemical Society on August 25, 2019.
"Transferring the cascade reactions of the enzymes to catalytically active nanoparticles could be a decisive step in the design of catalysts," Wolfgang Schuhmann sums up.
Particles with two active centers
Enzymes have different active centres for cascade reactions, which are specialised in certain reaction steps. For example, a single enzyme can produce a complex product from a relatively simple starting material. In order to imitate this concept, the researchers synthesised a particle with a silver core surrounded by a porous layer of copper. The silver core serves as the first active centre, the copper layer as the second. Intermediate products formed in the silver core then react in the copper layer to form more complex molecules that ultimately leave the particle.
In the present work, the German-Australian team showed that the electrochemical reduction of carbon dioxide can take place in the nanozymes. Several reaction steps on the silver core and copper sheath transform the starting material into ethanol or propanol.
"There are also other nanoparticles that can produce these products from CO2 without the cascade principle," says Wolfgang Schuhmann. "However, they require considerably more energy."
The researchers now want to further develop the concept of the cascade reaction in nanoparticles in order to be able to selectively produce even more valuable products such as ethylene or butanol.
Original publication:
Peter B. O'Mara, Patrick Wilde, Tania M. Benedetti, Corina Andronescu, Soshan Cheong, J. Justin Gooding, Richard D. Tilley, Wolfgang Schuhmann: Cascade reactions in nanozymes: spatially separated active sites inside Ag-core-porous-Cu-shell nanoparticles for multistep carbon dioxide reduction to higher organic molecules, in: Journal of the American Chemical Society, 2019
DOI: 10.1021/jacs.9b07310Further information:
Prof. Dr. Wolfgang Schuhmann, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Tel. 0234 32 26200, wolfgang.schuhmann@rub.deEditor: Dr. Julia Weiler, RUB
- Thomas Hammerschmidt appointed as editor of 'Machine Learning: Science and Technology' (MLST)
25th September 2019,
New IOP journal launched in 2019. Read original articleICAMS group leader Thomas Hammerschmidt is appointed as founding member of the Editorial Board of the new IOP journal 'Machine Learning: Science and Technology' (MLST). The mission for MLST is to uniquely bridge the application of machine learning techniques across a broad range of subject disciplines (including physics, materials science, chemistry, biology, medicine, earth science and space science) with new conceptual advances in machine learning methods motivated by physical insights, through a single, high impact open access journal.
Thomas Hammerschmidt is a group leader at ICAMS, RUB (c) ICAMS - Highly Efficient Magnetic Computers
25th September 2019,
Processor from the Petri Dish.
Electron microscope image of Magnetospirillum gryphiswaldense. Inside, the beads are only a few nanometers in diameter. © UDEA suitable culture medium, some heat and the computer grows all by itself: a processor made of special bacteria could process considerably more data for the same size than its silicon counterpart. Scientists from the Materials Chain at the University of Duisburg-Essen (UDE) report in the journal Nature Communications about their discovery of magnetic oscillations inside bacteria.
The unicellular organism has special innards: small magnetic spheres with a diameter of only 30 nanometers, lined up like a string of pearls. In nature, they are used for orientation along the earth's magnetic field.
Scientists led by Benjamin Zingsem from the UDE working group "Structure and Magnetism of Nanoscale Systems" and colleagues from the University of Oldenburg have now exposed these bacteria to magnetic fields of different strengths from different directions and generated magnetic oscillations ("magnons") in the particles. They noticed that bacteria lacking a certain protein form curved and branched chains that act like logical circuits: "If one excites several magnetic oscillations that carry different information, a new oscillation results in the magnons, the information of which is a logical linkage of the original oscillations," explains Zingsem. The Materials Chain researchers have now observed this magnonics for the first time in a biological system and on a nano-level. Previously, it had only been researched in larger microsystems.
As powerful as a human brain
The bacteria-based processor has several advantages: Since it does not work with electric current, it does not need to be cooled. This saves a lot of energy and enables much more complex processors. "This would make it possible to accommodate about a million times more circuits in one processor than before," says the physicist. A single computer could thus become as powerful as a human brain. In addition, the bacteria grow independently and without the use of environmentally harmful compounds, as in semiconductor production. Their exponential growth would also make it possible to react quickly to increased market demand. Production would therefore be much cheaper and more sustainable than with traditional semiconductor technology.
According to Zingsem, the next step is to control such systems using conventional methods: "We are working on feeding such systems with data and reliably reading out the results. Integration into conventional electronics is therefore only a matter of time."
Original publication:
Zingsem, B. et al. Biologically encoded magnonics. Nat. commun. 10, 4345 (2019).
DOI: 10.1038/s41467-019-12219-0Further information:
Benjamin Zingsem, Faculty of Physics and Research Centre Jülich, Tel. 0203 37-9 4411, benjamin.zingsem@uni-due.deEditor: Birte Vierjahn, Tel. 0203 37-9 8176, birte.vierjahn@uni-due.de
- Materials Chain Early Career Researchers' Forum
10th September 2019,
New Materials Chain Event Series.
Expert advice? Priceless for a career. Many of them will be given to young scientists from the materials sciences on September 16 at the 1st Materials Chain Early Career Researchers' Forum of the UA Ruhr in Dortmund. Registration is possible online.What should materials scientists consider when planning their careers? What about scholarships? What funding is available in the EU and how do I apply? Especially at the beginning of a career, young researchers need support. In this case, they are supported by the Materials Chain members Prof. André Gröschel (UDE), Prof. Corina Andronescu (UDE) and Prof. Anna Grünebohm (RUB).
The materials researchers answer questions on projects of the Federal Research Ministry, funding programmes such as the Emmy Noether Young Researchers Group or grants from the European Research Council. In addition, experts provide information on further funding opportunities through the DFG and the Marie-Sklodowska Curie Programme.
The event at the International Meeting Centre at TU Dortmund University is aimed at the approximately 1,000 doctoral students, postdocs, scientific group leaders and junior professors of the material science faculties in the UA Ruhr.
Further information and registration:
https://materials-chain.com/news-events/conferences/early-career-forum/
Alexander Heinemann, CENIDE - Center for Nanointegration Duisburg-Essen Tel. 0203/37 98175, alexander.heinemann@uni-due.de
Editor: Alexandra Nießen, 0203/37 91487, alexandra.niessen@uni-due.de - Proper Cooling for the Climate
6th September 2019,
Winner of Humboldt-Research-Award at Institute of Materials Science.
© Qiming ZhangCooled food and drugs are very important for many humans. Simultaneously, keeping them cold harms the environment. Prof. Qiming Zhang explores how optimal chilling reduces the climate change. The winner of the Humboldt-Research-Award is guest of Prof. Dr. Doru C. Lupascu at the UDE-Institute of Materials Science.
“The refrigerants in the compression-based cooling systems that are currently used in refrigerators or air conditioners are one of the leading causes of climate change”, Zhang says. That’s why he likes to develop a cooling at the UDE that has zero greenhouse gas emission and works without steam circuit. Basis for that are electrocaloric materials. This material class can also be used for saving energy or as an ultrasound source and is investigated by the professor of electrical engineering at his home university, the Pennsylvania State University (USA).
The electrocaloric effect is one property of certain materials that change its molecular structure when the electric field strength is changing and heat or cool off by this. Therefore cooling is possible without gaseous coolants. Nowadays, almost all devices are based on a (more or less climate-damaging) gas circulation. The gas is pushed in the circuit, expands, vaporizes, incorporates the heat from the fridge in its pipes and submits it outwards.
The cooling medium of electrocaloric materials is a solid body that absorbs the thermal energy in order to change its inner structure – quasi an ‘inner’ vaporization. For the removal a coolant (e.g. water) is still necessary, but the heat machine itself is the solid object that gets along without greenhouse gas.
Further information:
https://www.eecs.psu.edu/departments/directory-detail-g.aspx?q=QXZ1
https://www.uni-due.de/materials/
Prof. Dr. Qiming Zhang, PhD, qxz1@psu.edu
Prof. Dr. Doru C. Lupascu, Tel. 0201/18 3-2737, doru.lupascu@uni-due.deEditorship: Alexandra Niessen, Tel. 0203/37 9-1487, alexandra.niessen@uni-due.de
- Laboratory on the Icebreaker
28th August 2019,
Research in the Southern Ocean.
© Sea Ice Team, SCALE Antarctica Winter Cruise 2019Minus 19° Celsius and Arctic Ocean instead of 40° and Pool: Four UDE scientists have just spent three weeks on a research vessel in Antarctica. As part of an international team, they studied the ice in the Antarctic during the winter, which is crucial for the pole but also for the global climate.
100 scientists from 13 nations were on board the South African research vessel SA Agulhas II. For 21 days and 6,600 kilometres they took part in the major international climate protection research project SCALE (Southern Ocean Seasonal Experiment) to study the winter conditions in the Antarctic.
So it was not exactly the usual laboratory conditions under which the UDE engineers worked: "The cold was extreme," reports Dr. Carina Nisters. "We wore three layers of clothing all the time." And Prof. Jörg Schröder, head of the Institute of Mechanics, adds: "The temperature in the polar laboratory was constantly minus 10 degrees, which felt really warm compared to outside. But you couldn't stand it for more than an hour here either."
Earth's climate flywheel
The Southern Ocean is called the Earth's climate flywheel because it can absorb significant amounts of solar energy and increasing carbon dioxide emissions. But still too little is known about this gigantic system because of the adverse weather conditions and the remote location.
In a laboratory container on board the icebreaker, the scientists therefore took a close look at the physical, chemical, biological and mechanical properties of the ice. The "Sea Ice" team, which also included UDE researchers, took drill cores from large areas and from "pancake ice" - smaller floes with a bulging edge.
The waves that rolled under and alongside the 130-metre-long ship were up to 18 metres high. But even when the sea was calm, a sailor's walk was part of everyday life on board - tablets helped to prevent travel sickness.
Frazil ice
Using an apparatus specially designed for this expedition, the researchers also took and analysed samples of "Frazil ice". This consists of liquid water with the first frozen particles in it and only later becomes solid sea ice. Since the conditions in the Antarctic winter are particularly extreme, there are only a few data available so far. "Our results are now the basis for models that can analyse and predict the behaviour of clods under different conditions," explains Prof. Doru C. Lupascu, head of the Institute of Materials Science.
The expedition was led by the University of Cape Town (South Africa) and included 17 different research groups from the fields of biology, chemistry and engineering. It was funded by the South African National Research Foundation (NRF) through the South African National Antarctic Programme (SANAP), with contributions from the Department of Science and Innovation and the Department of Environmental Affairs.
in the picture:
SA Agulhas II paves its way through typical pancake iceFurther information:
Carina Nisters, Institute of Mechanics, Tel. 0201/18 3-3142, carina.nisters@uni-due.deEditor: Birte Vierjahn, Tel. 0203/37 9-2427, birte.vierjahn@uni-due.de
- Award for Sebastian Schlücker
19th August 2019,
Founder Competition of the sbm.
© smbProf. Sebastian Schlücker from the Faculty of Chemistry is keen to promote MINT subjects as early as primary school. Together with colleagues, he therefore distributes specially developed experiments with appropriate teaching/learning material. His idea won him 3rd place in the UDE's small business management (sbm) start-up competition. The 2nd place went to doctoral students of Prof. Angelika Heinzel.
28 business plans were submitted to the 20th round of the orientation course entrepreneurship from the small business management offer at the UDE. Chemistry professor Sebastian Schlücker together with Roland Grzeschick and Vi Tran were able to convince with the nano workshops for primary schools. For its excellent placement, the team now receives a virtual membership in sbm and six months of free office space in Tectrum.
Second place went to Nicolas Witte-Humperdinck, PhD student in the working group of Prof. Angelika Heinzel. Together with his colleagues Florian Nigbur and Christian Thommessen, he plans to found a consulting company in the energy sector. They want to make an active contribution to energy system transformation through a coordinated interplay of possible generation technologies and strategy development.
First place went to the two students Christopher Kremzow-Tennie and Dennis Pohl: They are planning to develop their own VR-based game that will ensure the survival of the village population in a post-apocalyptic Middle Ages.
In May 1999, the small business management (sbm) project was launched at the University of Duisburg-Essen on the Duisburg campus. Since then, it has coordinated and organized all activities aimed at promoting entrepreneurship and self-employment. The focus of the support measures is on training and support for people of all ages and professions interested in starting a business.
Editor: Birte Vierjahn, 0203 37-9 8176, birte.vierjahn@uni-due.de
- Junior Professor Sebastian Henke Researches Porous Glasses
12th August 2019,
Publication in Chemistry Journal. Read original article
© Nikolas Golsch/TU DortmundJunior Prof. Sebastian Henke and his team from the Faculty of Chemistry and Chemical Biology at TU Dortmund University have developed novel porous glasses that are thermally stable and can separate gas molecules due to different diffusion rates. The glasses will now contribute to the development of new membrane technologies for the energy-efficient separation of technologically important gases. The results of Henke and his team were recently published in the renowned journal "Journal of the American Chemical Society".
In order to produce one of the most important plastics, polypropylene, the industry needs very pure propene. However, this valuable gas occurs in conjunction with propane, which inhibits the production of plastics. In order to separate the two gases, which have very similar physical properties, complex and energy-intensive distillation processes are necessary. Junior Prof. Henke and his team have now been able to show that novel porous glasses made from so-called MOFs have great potential for energy-efficient separation of propene and propane. MOF stands for Metal-Organic-Framework, i.e. framework compounds of organic and inorganic molecules that can store and separate gases due to their porous, open structure.
MOFs are usually crystalline and therefore have a highly ordered network structure. The MOF glasses synthesised by Henke and his team, on the other hand, have a disordered, but nevertheless porous structure that is also significantly more thermally stable than its crystalline relatives. "From a physical point of view, the glasses are supercooled liquids. By heating, the glasses can be melted and then cast into moulds similar to liquid metal. The structure and porosity of the glass is retained. In principle, thin glass sheets can be formed in this way, which could then be used as gas-permeable membranes," explains Henke. In several tests, the researchers varied the composition of the MOF glasses: they combined different molecular building blocks of different sizes in order to influence the speed at which the gases diffuse through the pore network of the glasses. This enabled propene to diffuse through the glasses much faster - up to six times - than propane. This speed difference allows the gases to be separated.
Versatile application possibilities
In contrast to the time and energy consuming separation by distillation, membrane technology offers great economic and ecological advantages. In their publication, the chemists demonstrated the potential of the novel MOF glasses for the further development of this technology and designed a concept for such a MOF glass membrane. The next step is to "build" the membrane. In the long term, numerous applications will open up, ranging from batteries to fiber optic cables. Many other areas of application are conceivable, as glass has become indispensable for modern technologies.
- Moving Standing Wave Generated
12th August 2019,
Phenomenon in Video .
© UDEAn international team of scientists led by physicists from the Materials Chain has observed a new phenomenon: They have generated standing waves - which nevertheless run. The researchers have also published their discovery as a video in the scientific journal Physical Review B. The researchers have also published their findings in the form of a video.
A wave consists of nodes and anti-nodes. If you imagine this on a rope, the anti-nodes are the bulges that go down or up (mountains and valleys). Nodes are the points of the rope that lie exactly between mountain and valley. With a standing wave, nodes always remain in the same place, a anti-node only swings from bottom to top. There is no movement to the left or to the right. In contrast, there are running waves: If you make a rope vibrate strongly at one end, you create a wave that runs through it to the end.
Benjamin Zingsem from the research group of UDE Professor Michael Farle has now observed the apparent paradox for the first time: He worked with a magnetic material in which Dzyaloshinskii-Moriya interaction occurs: All dipoles - the tiny magnets that make up the material - are slightly twisted in a certain direction like screw windings. Physics calls this a chiral magnet.
If the system is now resonantly excited to vibrate, a standing wave with running properties is formed. This also has stationary nodes and anti-nodes "I had to look at it for a long time before I could put into words what it is. I only really understood it after watching a video of it," says Zingsem. Because standing waves are a fundamental phenomenon of physics, which one thought understood so far.
In such systems, the effect reveals previously unknown transport properties. For example, information can be stored, transmitted and processed via their magnetic oscillations without generating heat, as in conventional systems.
For the project, Zingsem worked with colleagues from the University of Colorado (USA) and the University of Glasgow (UK), among others.
Picture: Excerpt from a video showing the standing wave with running properties. White: nodes and anti-nodes of the standing wave that are traversed again and again. Green: Snapshot of the wave.
The phenomenon in the video: http://udue.de/standingWaveComparison
Original publication:
B.W. Zingsem, M. Farle, R.L. Stamps, and R.E. Camley, Unusual nature of confined modes in a chiral system: Directional transport in standing waves. Phys. Rev. B,99:214429, Jun 2019.
https://doi.org/10.1103/PhysRevB.99.214429Further information:
Benjamin Zingsem, Faculty of Physics and Research Centre Jülich, 0203 37-9 4411, benjamin.zingsem@uni-due.deEditor: Birte Vierjahn, 0203 37-9 8176, birte.vierjahn@uni-due.de
- Twisted Graphene
8th August 2019,
Publication in ACS NanoLetters .
© Horn-von HoegenGraphene does not like to be compressed, but instead forms twisted domains during epitaxial growth on an iridium substrate. Michael Horn-von Hoegen's team found this surprising occurrence of small angle rotations by a special Moiré pattern in high-resolution low-energy electron diffraction.
The thermal expansion of the substrate acts like an effective biaxial pressure, which is much better compensated by small angle rotation of the entire graphene layer than by its compression. This effect is also known as "rotational epitaxy". The results have now been published in "ACS NanoLetters".
Figure: Electron diffraction image of the Moiré pattern.
Original publication:
Temperature-Controlled Rotational Epitaxy of Graphene
Nano Lat. 2019, 19, 7, 4594-4600.
https://doi.org/10.1021/acs.nanolett.9b01565Further information and editorial office:
Prof. Dr. Horn-von Hoegen, Experimental Physics, Tel. 0203 379-1438/1439, michael.horn-von-hoegen@uni-due.de - Excellent Researcher and Good Friend
7th August 2019,
Obituary to Prof. Dr. Carsten Schmuck.
© UDEHe was appreciated as an expert as well as a textbook author, advisor and committed colleague: Prof. Dr. Carsten Schmuck passed away. The 51-year-old chemist has been teaching and researching at the University of Duisburg-Essen (UDE) since 2008. "In Carsten Schmuck we are losing not only an outstanding scientist, but also an esteemed advisor and friend. His death moves us all very much," said Prof. Dr. Maik Walpuski, Vice Dean of the Faculty of Chemistry.
Carsten Schmuck has made a name for himself as an excellent scientist: he discovered new binding motifs and applied combinatorial methods. In doing so, he broke new ground in supramolecular chemistry. He also created highly efficient ligands for proteins and new self-assembled materials. Schmuck was Vice-Chairman of the DFG Collaborative Research Centre Supramolecular Chemistry on Proteins and also a DFG Review Board member.
Carsten Schmuck was extremely popular and an important contact for young scientists. "With his pragmatic, but equally objective and prudent manner, he successfully worked as Dean for eight years to position the faculty as an interdisciplinary and research-oriented institution," said Walpuski. "He had clear goals in the further development of the faculty and the UDE. He always had an open ear for small and large problems".
Born in Oberhausen, Schmuck remained loyal to the Ruhr Area. He completed his chemistry studies in 1992 at Ruhr-Universität Bochum, where he also received his doctorate two years later. From 1995 to 1997 he was a fellow of the Feodor Lynen Foundation at Columbia University in New York. In 2001 he habilitated in Supramolecular and Bioorganic Chemistry at the University of Cologne, one year later he took up a professorship at the University of Würzburg. In 2008, Schmuck moved to the UDE and became Dean of the Faculty of Chemistry in 2011.
Editor: Cathrin Becker, Tel. 0203/379-1488, cathrin.becker@uni-due.de
- New Promotion College for the UA Ruhr
6th August 2019,
Medicine and Physics.
© Jürgen Huhn/TU DortmundFrom January 2020 on the Mercator Research Center Ruhr (MERCUR) will fund a new doctoral college within the University Alliance Ruhr (UA Ruhr) with more than half a million euros. In medical physics, TU Dortmund University and the University of Duisburg-Essen (UDE) will create new opportunities for doctoral studies.
"Precision particle therapy - practice-related physics and chemistry at the interface to medicine" is the name of the new doctoral college under the direction of Dortmund physics professor Kevin Kröninger. In the future, young scientists will be able to do their doctorate at the interface between physics, chemistry and medicine. The doctoral students will work on the promising topic of proton therapy, a special form of radiation therapy with protons. A beam of positively charged particles (protons) releases its radiation energy very focused in the tumor tissue and destroys it. Research at the doctoral college is intended to contribute to achieving even greater precision in irradiation. The college makes use of location advantages and synergies on site: The Faculty of Physics at TU Dortmund University offers the innovative medical physics course and the West German Proton Therapy Centre (WPE) at the University Hospital Essen gives doctoral students access to one of the few proton therapy centres in Germany. The third partner in the college is the Center for Nanointegration Duisburg-Essen (CENIDE) of the UDE with expertise in the field of nanoparticle preparation. Besides Prof. Kröninger from TU Dortmund University, Prof. Stephan Barcikowski (CENIDE and UDE), Prof. Bernhard Spaan (TU Dortmund University) and Prof. Beate Timmermann (WPE and UDE) are involved. The MERCUR grant amounts to around 590,000 euros over three years.
About the UA Ruhr
Since 2007, Ruhr-Universität Bochum, TU Dortmund University and the University of Duisburg-Essen have been working closely together strategically under the umbrella of the UA Ruhr. By joining forces, the services of the partner universities are systematically expanded. Under the motto "better together", there are now more than 100 cooperations in research, teaching and administration. With more than 120,000 students and almost 1,300 professors, the UA Ruhr is one of Germany's largest and most efficient science locations.
- Machining Working Group Brings Together Scientists From All Over Germany
5th August 2019,
Three Questions for Prof. Dirk Biermann.
© Jürgen Huhn/TU DortmundThe "Arbeitsgemeinschaft Zerspanung" had been founded at the end of June 2019 at TU Dortmund University: Eleven leading scientists in the field of machining from all over Germany came to Dortmund to participate in the founding meeting. The aim of the new working group is to promote cooperation in research and teaching in the field of machining. Machining means all manufacturing processes that give workpieces a certain geometric shape by separating material - for example by turning, drilling or milling. Prof. Dirk Biermann has been researching at the Institute of Machining Technology (Institut für Spanende Fertigung, ISF) at the TU Dortmund since 2007. He is a founding member of the new working group.
Professor Biermann, what are the advantages of cooperation between different universities?
Dirk Biermann: The working group represents scientific machining technology and would like to offer a platform for exchange. It thus strengthens the scientific community. For example, we can jointly prepare larger research initiatives in the field of machining production. In addition, we want to further develop teaching and coordinate the content and schedule of meetings and conferences.
What current challenges are you dealing with in machining?
Dirk Biermann: We are currently working on the machining of high-performance materials and on the targeted and high-precision adjustment of surfaces and their properties. When we optimize machining processes, we use simulations and modelling. This in turn requires interdisciplinary cooperation, for example with materials science, mechanics and computer science. Only together can the still numerous problems and questions be solved. Current applications can be found in the automotive and aerospace industries as well as in medical and energy technology.
What strengths is TU Dortmund University bringing to the new working group?Dirk Biermann: For more than four decades, the Institute of Machining Technology (Institut für Spanende Fertigung, ISF) has been involved in research and teaching on all relevant machining processes as well as on the IT environment of machining. The processes under consideration are turning, drilling, deep drilling, milling, grinding, honing and blasting. The implementation of virtual machining processes on the basis of various modeling concepts as well as the optimization in manufacturing technology are also the focus of the scientific work. Within TU Dortmund University, there are close relationships with the fields of materials technology and materials testing technology, the Institute for Forming Technology and Lightweight Construction, with all other facilities of the Faculty of Mechanical Engineering as well as with various professorships in computer science, statistics and mathematics. With regard to the intensive interdisciplinary cooperation with computer science, Dortmund is certainly a role model, as we have Prof. Petra Wiederkehr, a professor at the Faculty of Computer Science who focuses on the topic of "Virtual Machining". Prof. Wiederkehr is also a member of the new working group on machining.
- One Professor for Three Universities
30th July 2019,
UA Ruhr Professorship for Manfred Bayer.
© Roland Baege/TU DortmundProf. Manfred Bayer from the TU Dortmund will receive a UA Ruhr professorship, i.e. a joint professorship of the University Alliance Ruhr: The physicist will work closely with scientists from the Ruhr University Bochum (RUB) and the University Duisburg-Essen (UDE).
As a UA-Ruhr professor, Manfred Bayer will study novel materials using laser spectroscopy. In the UA Ruhr, the physicist forms an interface between physics, chemistry and materials science: The collaboration is intended to advance the understanding and further development of so-called 2D materials, which consist of only a single atomic layer. In particular, different 2D materials are to be combined with each other, such as semiconducting systems with superconducting or ferromagnetic systems, so that they influence each other. In this way, it will be possible in the future to produce low-cost components with low energy consumption and good environmental compatibility.
The Mercator Research Center Ruhr (MERCUR) is funding the new UA-Ruhr professorship with around one million euros, supporting the complementary strengths that the scientists at the three locations bring to the joint work: Duisburg-Essen, for example, will manufacture the materials and analyze them on the nanometer scale; a new manufacturing method for these systems is currently being established in Bochum. The two locations are also contributing to the theoretical description with different calculation methods, while the Dortmund physicists in Bayer's working group are mainly dedicated to optical investigation with advanced spectroscopy.
About the person
Prof. Manfred Bayer has been Professor of Experimental Physics with a focus on spectroscopy of condensed matter at the TU Dortmund since 2002. Since 2015 he is speaker of the German-Russian Collaborative Research Center/Transregios 160 "Coherent Manipulation of Interacting Spin Excitations in Customized Semiconductors" and since 2014 speaker of the SFB/TRR 142 "Customized Nonlinear Photonics". He brings with him an international network from which all participating institutions will benefit.
The UA Ruhr Professorships
The appointment of Manfred Bayer is the sixth joint Ruhr Area professorship. Physicist Prof. Claus M. Schneider from Duisburg-Essen was appointed to the first joint professorship in 2010. This was followed in 2013 by genome computer scientist Prof. Sven Rahmann from Duisburg-Essen and in 2017 by chemist Prof. Martina Havenith from Bochum and engineer computer scientist Prof. Petra Wiederkehr from Dortmund. In 2018 chemist Prof. Malte Behrens from Duisburg-Essen was appointed tUA Ruhr professor. The UA Ruhr professorship has been sponsored by MERCUR since 2013.
About the UA Ruhr
Since 2007, Ruhr-Universität Bochum, TU Dortmund University and the University of Duisburg-Essen have been working closely together strategically under the umbrella of the UA Ruhr. By joining forces, the services of the partner universities are systematically expanded. Under the motto "better together", there are now more than 100 cooperations in research, teaching and administration. With more than 120,000 students and almost 1,300 professors, the UA Ruhr is one of Germany's largest and most efficient science locations.
- Smallest Measurable Processes Recorded Individually
29th July 2019,
Dynamics in Quantum Dots.
© UDEColloquially, the term “quantum jump” is used to describe a tremendous development. In fact, it is the smallest change of state that can still be traced. Physicists from the Collaborative Research Center 1242 at the University of Duisburg-Essen (UDE) have now succeeded in measuring every single jump by optical means and drawing conclusions about the dynamics of the electrons inside a quantum dot. The journal Physical Review Letters reports on this in its 122nd issue.
The experimental setup included a quantum dot – i.e. a solid structure of only about 10,000 atoms – next to a reservoir with electrons. About 100 times per second an electron jumps back and forth between this structure and the reservoir. It can jump into a high or low energy state into the quantum dot and change inside from top to bottom. For the first time, the researchers were able to observe this change through these tiny jumps.
"This measurement of every single quantum jump is the maximum information that can be extracted from a quantum system, because there aren’t any other or faster processes that can be measured”, explains Dr. Martin Paul Geller from the Collaborative Research Center 1242 Non-Equilibrium Dynamics of Condensed Matter in the Time Domain. For the project, the team of experimental physicists collaborated with colleagues from theoretical physics in the working group of Professor Dr. Jürgen König (UDE). The theoretical physicists statistically analyzed the data and for the first time could made statements about the dynamics of the electrons in the quantum dot.
"In principle, we worked with a highly-sensitive optical and fast microscope that has still much room for improvement”, says Geller describing the measurement technology that has been refined by the researchers. Further optimization could outperform any electrical measurement in speed and spatial resolution.
Picture: Lower part: An electron (gray circle) can jump (gray and black arrow) between the quantum dot (ligh-blue hill) and the charge carrier reservoir (dark blue rectangle). The red arrows depicts light, which is used to observe these processes. Upper part: Every quantum jump (gray and black arrows) can be observed by the incident light.
Original publication:
Optical Detection of Single-Electron Tunneling into a Semiconductor Quantum Dot
A. Kurzmann, P. Stegmann, J. Kerski, R. Schott, A. Ludwig, A. D. Wieck, J. König, A. Lorke, and M. Geller
Phys. Rev. Lett. 122, 247403 (2019)
https://doi.org/10.1103/PhysRevLett.122.247403
Further information: Dr. Martin Paul Geller, Faculty of Physics, +49 203 37 9-2237, martin.geller@uni-due.de
Editor: Birte Vierjahn, +49 203 37 9-8176, birte.vierjahn@uni-due.de
- Optimization of BTA Deep Drilling Methods
26th July 2019,
DFG and Fraunhofer-Gesellschaft Support Transfer Project in Mechanical Engineering.
© Nikolas Golsch/TU DortmundProf. Dirk Biermann and Prof. Markus Stommel from the Faculty of Mechanical Engineering at TU Dortmund University, together with the Fraunhofer Institute for Non-Destructive Testing and practical partners, are researching the improvement of BTA deep drilling methods. The German Research Foundation (DFG) and the Fraunhofer-Gesellschaft are funding the project, which enables the transfer of scientific findings into applications, for three years.
For the first time, the DFG and the Fraunhofer-Gesellschaft are jointly funding seven projects to transfer findings from DFG-funded projects to industry. The funding for the selected cooperation projects amounts to a total of six million euros. The new projects involve trilateral cooperation between universities, Fraunhofer Institutes and companies. For the project "Light and vibration-damping hybrid FRP metal tubes with structure-integrated sensor technology for BTA deep drilling processes", the Faculty of Mechanical Engineering of TU Dortmund University is cooperating with the Fraunhofer Institute for Non-Destructive Testing in Saarbrücken and the application partners BGTB GmbH from Dortmund, CarboFibretec GmbH from Friedrichshafen and Kaiser Maschinenbau und Zerspanungstechnik GmbH & Co. KG from Toppenstedt. Project managers from TU Dortmund University are Prof. Dirk Biermann, head of the Institute of Machining Technology (ISF), and Prof. Markus Stommel, professor of plastics technology.
The aim of the project is to optimize BTA deep drilling. This is a process in which the drilling depths are many times greater than the diameters. Due to the required tool length, the tool vibrates more, resulting in greater wear on the cutting edges and guide pads and reduced drilling quality. The use of fibre-reinforced plastics (FRP), which have a heterogeneous structure, is intended to dampen the vibrations.
Close cooperation with companies
In the development of a hybrid FRP drill pipe, the project partners involved can draw on experience from basic research. Close cooperation with companies also ensures the expertise of industrial partners - from design to application validation. These in turn can benefit early on from innovations from research.
The seven trilateral projects now funded were selected from 20 submitted project proposals from engineering, natural and life sciences.
- International Symposium on Phase‑Field Modelling in Materials Science
22nd July 2019,
International Experts meet at Ruhr-Universität Bochum. Read original articleThe conference covers a broad field of theoretical modelling, numerical methods and applications related to phase-transitions, moving boundary problems, pattern formation and microstructure evolution in general. Also model integration into a multi-scale, multi-physics framework are of high interest. The covered topics include:
Participants of the Phase‑Field Symposium at Bochum in July 2019. (C) ICAMS, Ruhr-Universität Bochum.- Model development and analytics
- Numerical implementation and benchmark tests
- Microscopic / Mesoscopic phase-field models
- Phase‑field crystal
- Solidification and diffusion controlled transformation
- Rapid solidification, mixed mode transformation and strong deviation from equilibrium
- Solid state and structural transformation
- Interaction of dislocations with precipitates and grain boundaries
- Large deformation and fracture
- Material architecture, topology design and microstructure optimization
- High performance computing and aspects of hierarchical model integration
- Nanorings with Two Sides
22nd July 2019,
Self-Organizing Molecules.
© UDEThe tiny rings that chemists at the Center for Nanointegration (CENIDE) at the UDE create in the laboratory are as small as a bacterium. Self-organized, individual polymer chains form the flexible structures that can even squeeze themselves through cell membranes. This would enable them to deliver active substances in a very targeted manner. The renowned scientific journal ACS Nano reports on this in its current issue.
Take some chloroform, a few milligrams of polymer and mingle this solution with a soap mixture. This results in an emulsion from which chloroform slowly evaporates for several days. What remains are small polymer nanoparticles that consist of small rings inside. The structure looks like a striped Easter egg: many rings lie on top of each other, the largest in the middle, the smallest at the top and bottom. To stabilize them, they are chemically cross-linked in the core and then separated from each other.
"It is in general difficult to make rings from such soft matter as polymers," explains Andrea Steinhaus, PhD student in the research group of junior professor André Gröschel. "But we have found a good possibility that can be easily scaled up. This is immensely important with regard to industrial production".
The team of scientists also succeeded in producing rings with two different sides for the first time. They are called Janus nanorings after the Roman god with two faces: If you look at them like a bagel cut open to smear, the upper half is made of a different polymer than the lower half. This allows different properties to be set that are suitable for the respective application.
In the next step, the chemists want to manufacture discs and examine various filling patterns. The fundamental question here is the same: Which method can be used to build which structure? Because after all, it is essential for many applications to be able to specifically form complex nanostructures.
Original publication:
Confinement Assembly of ABC Triblock Terpolymers for the High-Yield Synthesis of Janus Nanorings, A. Steinhaus, R. Chakroun, M. Müllner, T. Nghiem, M. Hildebrandt, and A. H. Gröschel, ACS Nano 2019 13 (6), 6269-6278, DOI: https://doi.org/10.1021/acsnano.8b09546Photo: Microscopic image of individual rings. The largest has a diameter of about 500 nanometers.
Further information:
Andrea Steinhaus, +49 203 37 9-8219, andrea.steinhaus@uni-due.deEditor: Birte Vierjahn, +49 203 37 9-8176, birte.vierjahn@uni-due.de
- 2.8 Million Euros for Physicists
15th July 2019,
Let's get to the particle accelerators!.
© ESRF/P.JayetIt is about the properties of magnetic materials and tailor-made changes in novel materials: Two teams led by female physicists from the University of Duisburg-Essen (UDE) are being funded with a total of 2.8 million euros over three years. They are developing new instruments for experiments on particle accelerators.
The project, led by Dr. Katharina Ollefs, deals with novel, energy-efficient cooling using magnetic materials. The existing systems damage the environment or consume a lot of electricity. Magnetocaloric materials offer alternatives: their temperature can be changed by applying a magnetic field.
In the ULMAG (ULtimate MAGnetic Characterization) project, which is now being funded, Ollefs' team, together with colleagues from Technical University of Darmstadt, wants to investigate the elementary and magnetic properties of materials under exactly the same conditions. The experiments will take place at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. The ESRF generates X-rays that are 100 billion times more intense than the radiation used in hospitals.
"With the new device at the synchrotron radiation source, the smallest changes in magnetism and structure can be observed with high precision from the direct angle of the decisive atoms simultaneously during the phase transition. We hope that this will lead to groundbreaking new developments in magnetocaloric materials," explains Ollefs.
At CRYRING, an ion storage ring at the Helmholtz Centre for Heavy Ion Research in Darmstadt, the research team led by UDE Professor Marika Schleberger is using ion beams to investigate solid bodies. For this purpose, a measuring station at the 17-meter-wide ring, in which the ions fly at velocities of up to a quarter of the speed of light, will be equipped with novel instruments. They will be specially developed by the project partners of the UDE and the University of Giessen.
The researchers want to use these instruments to analyse the particles that are released when bombarded with ions in order to answer key questions: How can tailor-made changes in new materials be achieved by targeted removal of individual atoms? Into which subunits do biomolecules break under particle bombardment, and can this process be controlled? How can the detection sensitivity be further increased?
The Federal Ministry of Education and Research is funding both joint projects with 1.4 million euros over three years.
Further information:
Prof. Dr. Marika Schleberger, Experimental Physics, Tel. 0203/37 9-1600, marika.schleberger@uni-due.deEditor: Birte Vierjahn, Tel. 0203/37 9-8176, birte.vierjahn@uni-due.de
- Production of Catalyst in One Single Step
15th July 2019,
Patent Pending for Process.
Scanning electron microscope picture showing carbon nanowalls with a thickness of only a few nanometers. © UDENot much is possible without catalysts: More than 80% of all chemically manufactured products undergo a catalytic step during their production. The active material is usually platinum or another precious metal, so production is correspondingly expensive and requires several steps. Physicists at the University of Duisburg-Essen (UDE) have now filed a patent application for a process that produces highly active and long-term stable catalyst material in a single step.
The catalyst material produced by physicists Dr. Nicolas Wöhrl and Sebastian Tigges consists almost entirely of surface – and is therefore perfect for the purpose: the more surface available, the more reactions can take place simultaneously.
The promising material was formed in a plasma coating plant. The scientists let a carbon-containing powder with platinum atoms evaporate and introduced it into the plasma system through a carrier gas. At around 350°C, carbon walls, only a few nanometers thin, form along electrical field lines. They already comprise the platinum nanoparticles.
"As a scientist, you sometimes need to be lucky", says Wöhrl. "It worked quickly and it worked well. With a diameter of around 1.8 nanometers, the particles had the right size, are free of contaminations and have settled directly in the walls." The scientists are currently investigating how far the particles must be anchored in the walls in order to remain there permanently, but at the same time protrude far enough to serve as catalytic centers. The distribution and chemical structure of walls and nanoparticles can be controlled independently by the process.
In the "MoRE InnoMat" project, the physicists are already working with chemists from UDE and industrial partners who are scaling the process to their standards. In collaboration with the Hydrogen and Fuel Cell Center (ZBT), a demonstrator with a surface area of just a few cm2 is currently being built for the development of a micro fuel cell.
"We are generally open to cooperation with various fields”, explains Wöhrl. "This is the only way we can sound out the limits of our process." Tigges adds: "How awesome would it be if we ever held a smartphone in our hands that is based on our material?"
The project was funded by the European Regional Development Fund (ERDF).
Further information: Dr. Nicolas Wöhrl, Faculty of Physics, +49 203 37 9-3131, nicolas.woehrl@uni-due.de
Editor: Birte Vierjahn, +49 203 37 9-8176, birte.vierjahn@uni-due.de
- Discoveries are the Main Task
10th July 2019,
Interview.
© RUB MarquardProfessor Alfred Ludwig, Ruhr-Universität Bochum (RUB), has renamed his chair. In an interview he reveals why.
A lot will depend on materials in the future, for example whether the energy revolution will succeed. Materials researchers in Bochum have made a lot of headlines with their methods in recent months. Professor Alfred Ludwig, Managing Director of the Center for Interfacial-Dominated High-Performance Materials at RUB, dares to take a look ahead.
Professor Ludwig, your chair is now called "Materials Discovery and Interfaces". So you are expecting discoveries at your chair - what makes you so confident?
We have already made some discoveries in recent years, but also a lot of work on improving already known materials. With the new name we are expressing that we now want to perceive the discovery of new materials as our main task.
We have developed the tools for this in the last 16 years. Now we want to use them, but at the same time accelerate the process with the methods of material informatics.
Which properties of materials are particularly popular at the moment?
I think that new materials are urgently needed for the energy systems of the future, for example new catalysts for fuel cells and new permanent magnets. But we also need new multifunctional materials, such as shape memory alloys, for the continuing megatrend of miniaturization and functional integration.
What will be the greatest challenges for materials research in the coming years?
To master the application of materials informatics up to autonomous experiments.
If we look ten years into the future of materials research: How will we then develop a tailor-made material?
Inverse design will then be possible, i.e. the desired materials properties will be defined and it will then be possible to produce the desired material directly. To do this, we must now create the database with automated experiments and intensify cooperation between experimental and computer-based materials researchers.
I think we have optimal conditions for this in Bochum.
Editor: Meike Drießen, meike.driessen@uv.rub.de
- How to Get New Materials Faster
10th July 2019,
Materials Research.
© RUB, DrießenMaterials libraries, high-throughput experiments, big data and artificial intelligence will help to ensure that new discoveries are no longer left to chance.
A lot depends on new materials, for example efficient energy conversion for the environmentally friendly drives of the future. The discovery of such materials still depends far too much on chance, says Prof. Dr. Alfred Ludwig, holder of the chair "Materials Discovery and Interfaces" at Ruhr-Universität Bochum (RUB). In the journal NPJ Computational Materials of July 10, 2019, he describes how digitization and artificial intelligence could make this possible more purposefully and quickly in the future.
An unexplored cosmos of possible materials
The amount of potential new materials that can be composed of the elements of the periodic table is unmanageable - even if one limits oneself to the 40 to 50 elements that are non-toxic, environmentally friendly and present in sufficient quantity on earth. Most of these possibilities are still unexplored. In the past, discoveries were often made by chance.
New methods of producing such materials open up the possibility of proceeding more efficiently. "By coating a carrier material from three or more different directions with atoms of different elements in our laboratory, which are mixed in different amounts depending on the location on the carrier, we produce so-called thin-film materials libraries," explains Alfred Ludwig.
Analysis using high-throughput methods
In order to make these libraries usable, however, they must not only be produced in a high-throughput process, but the properties of the materials recorded in them must also be analyzed just as efficiently. This is the only way to find out whether at any point there is a material composition in the library that has interesting properties for an application. "In order to accelerate the entire process of discovering new materials, it would be desirable for not only the measurements but also the analyses to be automated," says Alfred Ludwig.
At least partially automated, he would also like to use a database to cope with the enormous amount of materials data to be expected. "It is also important that these data are compatible for research groups from different disciplines," he points out. Not only the data of promising element compositions, but also that of all others should be documented. "This serves to enable machine learning and artificial intelligence to support science in the search for new materials," says Ludwig.
Original publicationAlfred Ludwig: Discovery of new materials using combinatorial synthesis and high-throughput characterization of thin-film materials libraries combined with computational methods, in: NPJ Computational Materials 2019, DOI: 10.1038/s41524-019-0205-0
Editor: Meike Drießen, meike.driessen@uv.rub.de
- With Diamonds to Quantum Computers and Mini-sensors
8th July 2019,
Researchers of the UA Ruhr Deliberately Place Flaws in the Gemstones..
© TU Dortmund, Nikolas GolschScientists from TU Dortmund University, Ruhr-Universität Bochum and the University of Duisburg-Essen deliberately place flaws in high-purity diamonds and investigate them. They are thus laying the foundation for quantum computer technology and tiny sensors. The results have now been published in the renowned journal "Physical Review Materials".
"Diamonds are a girl's best friend": The valuable gemstones are extremely popular in rings or ear studs. But the crystals are also of interest for science, even though these diamonds resemble the cut gemstones very little. A team of physicists from the three UA Ruhr universities places small impurities in the crystal structures and investigates how these can be used in quantum computers or as microscopically small sensors. Their results have now been presented in Physical Review Materials, one of the most respected physics journals.
The atomic lattice a diamond is made of is not as perfect as one would expect. Often there are impurities and defects in the structure. It is precisely these defects that are interesting for a UA Ruhr research group, namely a certain type, the so-called NV centers. The N stands for nitrogen and the V for vacancy. NV centres also exist in nature. However, they can also be produced artificially by shooting a nitrogen atom into a diamond crystal lattice, which usually consists of carbon. This ejects two carbon atoms, the nitrogen atom sits in one position and the neighboring position remains empty.
The research is a cooperation project of the three universities of the University Alliance Ruhr funded by the Mercator Research Center Ruhr (MERCUR): Colleagues at the University of Duisburg-Essen produce the diamonds by depositing an ionized molecular mixture on a substrate. The diamond thus grows layer by layer on this substrate. The researchers learned how best to build the diamond layers and which growth parameters are optimal.
The diamonds were then transfered to Ruhr-Universität Bochum. There, the scientists found out how best to shoot the nitrogen ions into the crystals in order to create the NV centers. This caused problems at the beginning, because a diamond is a very bad electrical conductor.
The crystals were then examined at TU Dortmund University. The researchers led by Tanmoy Chakraborty, Fabian Lehmann and Jingfu Zhang from Professor Dieter Suter's research group have set up several experiments with which they can investigate the crystals very specifically. In this way, they can see whether there is an NV centre with an electron at the desired location, without an electron or something completely different.
The results can be used for further research into NV centres and thus advance the development of quantum computers. Each NV centre contains one or more spins that can be used to store quantum information. In a usual hard disk, spins are oriented in one direction or the other. The state 0, for example, would stand for the spin pointing upwards. 1 accordingly means that the spin points downwards. The difference to a standard computer is that a quantum computer that would work with these NV centers, for example, could not only have the state "0" or "1", but also a so-called superposition state. So the spin can be in the state 0 as well as in the state 1. This allows you to perform calculations with both initial states at the same time. At 1000 bits, 21000 calculations can be done - which is enormous.
At the same time, tiny sensors can be developed on the basis of NV centers. For example, research is being carried out into introducing very small diamonds into cells and thus measuring the temperature inside the cells.
Publication: T. Chakraborty, F. Lehmann, J. Zhang, S. Borgsdorf, N. Wöhrl, R. Remfort, V. Buck, U. Köhler, and D. Suter: CVD growth of ultrapure diamond, generation of NV centers by ion implantation, and their spectroscopic characterization for quantum technological applications. Phys. Rev. Materials 3, 065205.
https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.3.065205Editor: Lena Reil, 0231/755-5449, lena.reil@tu-dortmund.de
- A Flash of Lightning Under Water
26th June 2019,
Plasma Research.
© RUB, Kramer
For only a few nanoseconds, a plasma tears the water apart. It may regenerate catalytic surfaces at the push of a button.Among other things, electrochemical cells help to recycle CO2. However, the catalytic surfaces wear out in the process. The team from Collaborative Research Centre 1316 "Transient atmospheric pressure plasmas: from plasma to liquid to solid" at Ruhr-Universität Bochum (RUB) is investigating how they could be regenerated at the push of a button using an extreme plasma in water. Using optical spectroscopy and modelling, for the first time the team was able to comprehensively investigate such underwater plasmas, which only exist for a few nanoseconds, and thus theoretically describe the conditions during plasma ignition. They report in the journal "Plasma Sources Science and Technology" of June 4, 2019.
Plasmas are ionized gases: They are formed when energy is supplied from a gas that then contains free charge carriers. In nature, plasmas occur, for example, inside stars or on Earth as polar lights. In technology, plasmas are used to generate light in fluorescent tubes, or to produce new materials for microelectronics. "Normally, plasmas are generated in the gas phase, for example in the air or in noble gases," explains Katharina Grosse from the RUB's Chair of Experimental Physics II.Cracks in water
In the current study, the researchers have generated plasmas directly in a liquid. They applied a high voltage for several billionths of a second to a hair-thin electrode immersed in the liquid. The ignition of the plasma creates a high negative pressure difference at the tip of the electrode, which causes cracks to form in the liquid. The plasma then spreads in these cracks. "The plasma can be easily compared to a flash of lightning, only here under water," says Katharina Grosse.
Hotter than the sun
Using fast optical spectroscopy in combination with fluid dynamics modelling, the research team was able to elucidate the variation of power, pressure and temperature in these plasmas. "We have seen that these plasmas consume up to 100 kilowatts of power for a short time, which is equivalent to the connected load of several detached houses," said Professor Achim von Keudell, holder of the Chair of Experimental Physics II. In addition, this produces pressures of several thousand bar, which corresponds to or even exceeds the pressure at the lowest point in the Pacific. After all, temperatures of many thousands of degrees similar to the surface temperature of the sun and beyond are generated briefly.
Water is broken down into its components
These extreme conditions exist only for a very short time. "Previous investigations have concentrated primarily on underwater plasmas in the microsecond range," explains Katharina Grosse. "During this time, the water molecules still have the opportunity to balance the pressure of the plasma. In the extreme plasmas in the nanosecond range that have now been investigated, faster processes take place. The water cannot equalize the pressure, and the molecules are broken down into their individual parts. "The oxygen released as a result is particularly important for catalytic surfaces in electrochemical cells," explains Katharina Grosse. "It can reoxidize such surfaces so that they can be regenerated and fully develop their catalytic activity again. In addition, dissolved reagents can also be activated in water, which facilitates catalysis processes."
Editor: Meike Drießen meike.driessen@uv.rub.de
- High Reaction Rates Even Without Precious Metals
19th June 2019,
Catalysis.
In this shielded cell, the researchers are testing the nanoparticles in electrochemical experiments. © RUB/KramerNon-precious metal nanoparticles could one day replace expensive catalysts for hydrogen production.
However, it is often difficult to determine what reaction rates they can achieve, especially when it comes to oxide particles. This is because the particles must be attached to the electrode using a binder and conductive additives, which distort the results.
With the aid of electrochemical analyses of individual particles, researchers have now succeeded in determining the activity and substance conversion of nanocatalysts made from cobalt iron oxide – without any binders. The team led by Professor Kristina Tschulik from Ruhr-Universität Bochum reports together with Professor Stephan Schulz from the University of Duisburg-Essen and colleagues from Dresden in the Journal of the American Chemical Society.
"The development of non-precious metal catalysts plays a decisive role in the realisation of the energy revolution, as only they are cheap and available in sufficient quantities to produce the required quantities of renewable fuels," says Kristina Tschulik, member of the Materials Chain and the Ruhr Explores Solvation Excellence Cluster (Resolv). "Learning more about the activities of nanocatalysts is indispensable for the efficient further development of non-precious metal catalysts."
Editor: Julia Weiler julia.weiler@uv.rub.de
- TU Dortmund University and Partners are Researching 5G
19th June 2019,
Millions in Funding from the State of North Rhine-Westphalia.
© TU DortmundThe new 5G generation of mobile communications forms the basis for an immense boost to innovation. The new research project "Competence Center 5G.NRW" (CC5G.NRW) aims to help North Rhine-Westphalia become the lead market for 5G. The state is providing 3.3 million euros in funding for this over a period of three years, of which around 1.2 million euros will go to TU Dortmund University.
As part of the research project, TU Dortmund University will be responsible for setting up and operating a flexible 5G experimental platform, which will enable companies to implement innovative 5G demonstrators "on site" in a unique way. When Prof. Christian Wietfeld handed over the funding decision by Prof. Andreas Pinkwart, Minister of Economics, Innovation, Digitisation and Energy of the State of North Rhine-Westphalia, he emphasised that "in addition to the high bandwidths, the focus is on fulfilling quality guarantees for highly reliable and highly scalable communication via 5G network slicing".
"Bridge between basic research and innovative application scenarios."
The team of Dortmund scientists is investigating the use of the currently auctioned 5G frequencies and will also test the mobile Gigabit transmission in the new 5G frequency range to be developed at 26 GHz with innovative, dynamically tracking antennas. Prof. Gabriele Sadowski, Prorector of Research at TU Dortmund University and member of the Materials Chain, is pleased that "with the Competence Center 5G.NRW, a bridge can be built between basic research in Dortmund's DFG Collaborative Research Centre 876 and innovative 5G deployment scenarios in NRW companies".
The Competence Center 5G.NRW is supported by four partners: Under the consortium leadership of the Institute for Systems Research in Information, Communication and Media Technology (SIKoM+) at Bergische Universität Wuppertal, these are TU Dortmund University, the University of Duisburg-Essen (UDE) and the Institute FIR at RWTH Aachen. The powerful consortium wants to accelerate the introduction of 5G technology in order to test its strengths and weaknesses in practice. From this, realistic recommendations for the application are to deduce and for the optimization of the systems, a contribution is to be made.
Use of 5G important for increasing industrial digitisation
For the increasing industrial digitization, the mobile radio standard 5G will realize the necessary quality, speed and capacity of the cross-linking and data transmission. Applications such as autonomous driving, remote robot surgery and augmented reality support in maintenance and repair situations will be enabled and continuously improved. In the "Competence Center 5G.NRW" research project, technical entry barriers for companies are reduced, economic potential for vertical markets - such as automotive and mobility, energy, food and agriculture, smart cities, health care and production and many more - is developed and innovations are accelerated. Prof. Dr. Andreas Pinkwart, Minister for Economic Affairs, Innovation, Digitisation and Energy of the State of North Rhine-Westphalia, presented the funding decision to representatives of the project consortium on Monday, 17 June.
- Teaching Prize for Three Chemists
18th June 2019,
Award at the Dies Academicus .
© UDETogether, they are involved in the lecture series "Functional Supramolecular Materials", now Jun.-Prof. Dr. Michael Giese, Dr. Jochen Niemeyer and Jun.-Prof. Dr. Jens Voskuhl receive this year's UDE Teaching Award. The award was presented at the Dies Academicus on June 17, 2019.
They are all connected by supramolecular chemistry. Against this background, the three early career scientists redesigned the master's lecture "Functional Supramolecular Materials" and offered it for the first time in the summer semester 2018. Due to the excellent student evaluation and their commitment to the students, which went far beyond the actual courses, the chemists will be honored with this year's teaching award.
Michael Giese, junior professor of the Professor-Werdelmann Foundation, focuses his research on the synthesis and analysis of supramolecular functional aggregates, especially those with liquid crystalline properties. The aim of his research is the development of novel supramolecular liquid crystals for applications in optical and electronic devices, such as organic solar cells or light emitting diodes.
Jochen Niemeyer has been habilitating at the university since 2014 as head of a junior research group. The goal of his research is the development of new supramolecular chemosensors and catalysts, in particular by using multifunctional systems. Chemosensors are of particular interest against the background of bioanalytical and diagnostic questions, while efficient catalyst systems enable the resource-saving production of chemical intermediates and energy carriers.
Jens Voskuhl is junior professor for biosupramolecular chemistry at the UDE. He is mainly involved in the construction of new supramolecular functional systems and their application in biological and medical contexts. The new findings and methods are relevant for the investigation of the interaction with proteins by artificial ligands.
The awarding of the teaching prize shows that the three researchers obviously convey this knowledge outstandingly well. Congratulations!
Further information and editorial office: Sarah Heuser, sarah.heuser@stud.uni-due.de - Wolfgang Schuhmann was Honoured in Ireland
27th May 2019,
Award Ceremony.
© RUB, KramerThe Bochum scientist is now one of the most decorated researchers in the International Association of Bioelectrochemistry.
The Bochum chemist Prof. Dr. Wolfgang Schuhmann has received the renowned Giulio Milazzo Award of the Bioelectrochemical Society, endowed with € 2,000. The prize was awarded on 26 May 2019 at the annual conference of the international association in Limerick, Ireland.
Wolfgang Schumann studied chemistry at the University of Karlsruhe and received his doctorate from the Technical University of Munich. Since 1996 he has been Professor of Analytical Chemistry at the RUB, where he is also a member of the Ruhr Explores Solvation Cluster of Excellence, which has been funded by the German Research Foundation since 2012.multiple award-winning
Schuhmann is author and co-author of about 650 scientific publications and has been decorated many times. In 2000 he received the "Biosensors and Bioelectronics Award". In 2008 he was a Fellow of the Royal Society of Chemistry and received the Julius von Haast Fellowship Award of the Royal Society of New Zealand and the Alexander von Humboldt Foundation. In 2011 he received the "Katsumi Niki Award" of the International Society of Electrochemistry. In 2014 Schuhmann was awarded the Howard Fellowship of the University of New South Wales in Sydney. Most recently, he was awarded the "Alessandro Volta Medal" of the Electrochemical Society in October 2018 and an Advanced Grant of the European Research Council in 2019.
Editor: Arne Dessaul, arne.dessaul@uv.rub.de
- Materials that Cool, Control, Store
24th May 2019,
New Emmy Noether Group.
© RUB, MarquardAnna Grünebohm calculates the building instructions for tailor-made materials.
Movement or temperature changes can be converted into electrical current, ferroelectric materials can do that and more. Optimizing them is the goal of Dr. Anna Grünebohm's new Emmy Noether junior research group at the Interdisciplinary Centre for Materials Simulation (ICAMS) at the RUB. The group "Scale-bridging computational design of multifunctional ferroelectric composites" has been funded by the German Research Foundation (DFG) with over 1.3 million euros for six years since May 1, 2019. Two doctoral positions are currently advertised.
Controlling small movements
The research focus of the group is on oxides with a perovskite structure in which different ions and thus different properties can be incorporated, just like in a Lego building set. Ferroelectric perovskites are particularly interesting because they contain ordered electrical dipoles that can be aligned by applying an electric field. This causes an elastic distortion in the material. "This is already being used today for piezoelectric actuators: small components that control tiny movements, for example in cameras," explains Anna Grünebohm.
Harvesting energy
In addition, such materials can also be used to generate electrical energy or for new environmentally friendly cooling technologies. "The exciting thing is that electrical energy can be harvested: You can generate electricity from temperature changes or movements that you have anyway. Examples are waste heat or a radio light switch where the movement of the button simultaneously generates the current for the radio signal," describes Anna Grünebohm.
"Unfortunately, such materials often contain lead, and that one would like to avoid," says the researcher. Using computer simulations, she hopes to gain a deeper understanding of the mechanisms involved in such materials and predict nanostructured materials with tailor-made properties. This will lead to a kind of construction manual for new materials for experimental collaboration partners.
Editor: Meike Drießen, meike.driessen@uv.rub.de
- Calculating the Internal Structure of Metals
24th May 2019,
Materials Science and Statistics join forces.
© RUB, KramerStatistical methods should help to optimize material properties more easily and quickly.
The microstructure of metals influences properties such as the durability and formability of materials. A special role is played by grain boundaries at which material areas of different spatial orientation adjoin each other. By mathematically modelling the processes at these grain boundaries, a research team at the Ruhr University Bochum (RUB) aims to contribute to the faster optimisation of materials. The German Research Foundation is funding the project "Efficient sampling and parametrization of the grain boundary geometry and composition space: atomistic simulation meets statistical methodology" at the Chair of Stochastics of the Faculty of Mathematics and at the Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) with approximately 600,000 euros for three years.
Grain boundaries describe in five dimensions
Describing grain boundaries in metals is very complicated: "We describe their geometry in five dimensions," explains Dr. Rebecca Janisch of ICAMS. One of the reasons for this is that the grains, some of which are only a few nanometers in size, are twisted against each other in the metal. This twisted position of the grains also results in individual atoms being shifted at the interfaces and forced out of their preferred position. "This means that a certain amount of energy is stored in the material," says Rebecca Janisch.
This grain boundary energy and material properties can be influenced by the selection of certain starting metals for alloys or by the addition of foreign atoms that accumulate at the grain boundaries - a process known as segregation. In order to be able to optimize the properties of a material more quickly and easily, the researchers want to model these processes mathematically. "Our goal is to develop an efficient high-throughput method for numerical simulations to determine grain boundary and segregation energies," said Prof. Dr. Holger Dette, head of the Chair of Stochastics at the RUB.
Predictions for alloys
"We will then be able to predict how often certain types of grain boundaries occur in an alloy of a certain composition," explains Janisch. To develop the new algorithms, the scientists use methods from mathematical statistics, representation theory to model grain boundary symmetries, and optimization.
Editor: Meike Drießen, meike.driessen@uv.rub.de
- Particles Out of the Flame
20th May 2019,
Humboldt Research Award Winner at the NETZ.
© privatTo improve car engines, produce nanomaterials or design rocket engines, it is essential to understand combustion processes. Professor Hai Wang from Stanford University (USA) is an expert in this field. As winner of the prestigious Research Award of the Alexander von Humboldt Foundation, he is currently a guest researcher at the NanoEnergieTechnikZentrum (NETZ) of the University of Duisburg-Essen (UDE).
Hai Wang, Professor of Mechanical Engineering at the renowned university in Silicon Valley, has been collaborating with his German colleagues for several years. Now, the Humboldt Research Award enables him to spend around six months in Duisburg to directly collaborate with his colleagues in the NETZ. He is looking forward to the collaboration: „Professor Schulz is making dazzling advances in understanding and making advanced materials from gas-phase synthesis. His research group is leading in many aspects of this research field in the world. Therefore, I am extremely delighted to have the opportunity to work with him and I hope that our collaboration will produce impactful results for years to come.”
Wang is internationally known for his work in combustion and aerosol research, especially in the fields of soot formation, reaction modeling and nanomaterials synthesis. He has been a key contributor to energy research and development, both for basic research and for industrial applications. His current research interests include the production of nanomaterials in flames. He has recently succeeded in processing the emerging carbon nanoparticles into nanodiamonds that are used widely: From fluorescent marking in medical applications to LEDs with variable colors.
The collaboration with Professor Schulz's group focuses primarily on basic research: "We are working on a unified theory on the behavior of nanoparticles in different precursors and settings during synthesis. In the long term, we want to be able to define exactly which products we will receive at the end of the process, even before we start it”, Schulz explains.
The Humboldt Research Award is granted to foreign scientists of all disciplines for their achievements as a whole, which have had a lasting impact on their own discipline and which are expected to contribute to future excellence. The award is valued at 60,000 € and enables the prizewinners to carry out research projects in Germany with peers of their own choice.
Further information: Prof. Christof Schulz, Reactive Fluids (IVG), +49 203 37 9-8161, christof.schulz@uni-due.de
Editor: Birte Vierjahn, +49 203 37 9-8176, birte.vierjahn@uni-due.de
- Applying Precious Metal Catalysts Economically
15th May 2019,
Chemistry.
© RUB, MarquardPrecious metal nanoparticles of platinum and gold are excellent catalysts. But they are expensive and rare. A new method makes it possible to save material.
Researchers at Ruhr-Universität Bochum and the Fritz Haber Institute Berlin have developed a new method of using rare and expensive catalysts as sparingly as possible. They enclosed a precious metal salt in outer shells, tiny micelles, and had them strike against a carbon electrode, thus coating the surface with nanoparticles of the precious metal contained in the micelles. At the same time, the team was able to precisely analyse how much of the metal was deposited. The researchers then showed that the electrode coated in this manner could efficiently catalyse the oxygen reduction, which is the limiting chemical process in fuel cells.
The team led by Professor Kristina Tschulik and Mathies Evers from the Research Group for Electrochemistry and Nanoscale Materials describes the process in the journal “Angewandte Chemie”, published online in advance on 11 April 2019.
“Only flat substrates can be coated uniformly with nanoparticles using standard methods,” says Kristina Tschulik. “Our process means that even complex surfaces can be loaded uniformly with a catalyst.”
Editor: Julia Weiler, julia.weiler@uv.rub.de
15th May 2019,
Self-Organizing Molecules.
Stacked Janus nanocups, before being separated. © UDE
They look like interlocking egg cups, but a hen's egg is 100,000 times as thick as one of the miniature cups: Scientists at the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) have made polymers to form themselves into tiny cups on their own. They could, for example, be used to remove oil residues from water. The scientists have published their results in the journal "Angewandte Chemie".
The first step is a very thin long chain of so-called triblock terpolymers – a kind of plastic. If many of them are added to a droplet of a solvent, they automatically adapt their shape to the round boundary. When the solvent evaporates, the drop becomes smaller and the polymer cup structure shrinks with it. What remains are the cups, which, like Russian Matryoshka dolls, lie one inside the other. Xiaolian Qiang, PhD candidate in the research group of junior professor André Gröschel, then separates them in several steps.
"Such particles are called ‘Janus particles’, because they have two sides with different properties", the 29-year-old explains. "The term comes from the Roman god Janus, who had two faces." Everyone knows the particle’s opposite chemical properties from soap: One half is hydrophilic, i.e. it dissolves well in water. The other half is hydrophobic like a drop of oil and therefore insoluble in water. In Qiang's experiments, 50 percent of the cups are produced with hydrophilic inner and hydrophobic outer sides. The other half is the other way round.
Qiang utilizes this principle to fill the small vessels with nanoparticles, for example. If she surrounds the particles with a solvent they do not like, they flee into the interior of the cup with the correspondingly opposite property. In this way it is possible to absorb oil residues from water or to transport substances through an aqueous environment – e.g. blood.
Now, Qiang and her team work on creating only one of the two variants.
Original publication: X. Qiang, A. Steinhaus, C. Chen, R. Chakroun, A.H. Gröschel: Template-Free Synthesis and Selective Filling of Janus Nanocups.
Angew. Chem. Int. Ed. 2019, 58, 7122 –7126
DOI: doi.org/10.1002/anie.201814014
Further information: Xiaolian Qiang, +49 203 37-98213, xiaolian.qiang@uni-due.de
Editor: Birte Vierjahn, +49 203 37-98176, birte.vierjahn@uni-due.de
6th May 2019,
Materials Research.
© RUB, Marquard
Numerous chemical reactions relevant for the energy revolution are highly complex and result in considerable energy losses. This is the reason why energy conversion and storage systems or fuel cells are not yet widely used in commercial applications. Researchers at Ruhr-Universität Bochum (RUB) and Max-Planck-Institut für Eisenforschung in Düsseldorf are now reporting on a new class of catalysts that is theoretically suitable for universal use. These so-called high entropy alloys are formed by mixing close to equal proportions of five or more elements. They might finally push the boundaries of traditional catalysts that have been unsurpassable for decades. The research team describes their uncommon electrocatalytic working principles as well as their potential for systematic application in the journal “ACS Energy Letters” from 17. April 2019.
Material libraries for electrocatalysis researchThe material class of high entropy alloys features physical properties that have considerable potential for numerous applications. In oxygen reduction, they have already reached the activity of a platinum catalyst.
“At our department, we have unique methods at our disposal to manufacture these complex materials from five source elements in different compositions in form of thin film or nanoparticle libraries,” explains Professor Alfred Ludwig from the Chair of Materials for Microtechnology at RUB. The atoms of the source elements blend in plasma and form nanoparticles in a substrate of ionic liquid. If the nanoparticles are located in the vicinity of the respective atom source, the percentage of atoms from that source is higher in the respective particle. “Very limited research has as yet been conducted into the usage of such materials in electrocatalysis,” says Ludwig.
Manipulating individual reaction stagesThis is expected to change in the near future. The researchers have postulated that the unique interactions of different neighbouring elements might pave the way for replacing noble metals with equivalent materials. “Our latest research has unearthed other unique characteristics, for example the fact that this class may also affect the interdependencies among individual reaction steps,” says Tobias Löffler, PhD researcher at the Center for Electrochemical Sciences at RUB's Chair of Analytical Chemistry. “Thus, it would contribute to solving one of the major problems of many energy conversion reactions, namely otherwise unavoidable great energy losses. The theoretical possibilities seem almost too good to be true.”
Foundation for ongoing researchIn order to promote rapid progress, the team from Bochum and Düsseldorf has described its initial findings with the aim of interpreting first characteristic observations, outlining the challenges, and putting forward first guidelines – all of which are conducive to advancing research. “The complexity of the alloy is reflected in the research results, and many analyses will be necessary before one can assess its actual potential. Still, none of the findings to date precludes a breakthrough,” supposes Professor Wolfgang Schuhmann, Chair of Analytical Chemistry at RUB.
Visualisation in 3DThe characterisation of catalyst nanoparticles, too, is conducive to research. “In order to gain an indication of how, exactly, the activity is affected by the structure, high-resolution visualisation of the catalyst surface on the atomic level is a helpful tool, preferably in 3D,” says Professor Christina Scheu from Max-Planck-Institut für Eisenforschung in Düsseldorf. Researchers have already demonstrated that this is an attainable goal – if not yet applied to this class of catalysts.
The question if such catalysts will facilitate the transition to sustainable energy management remains to be answered. “With our studies, we intend to lay the foundation for ongoing research in this field,” conclude the authors.
Editor: Meike Drießen
3rd May 2019,
Chemistry.
© RUB, Marquard
Nanoparticles can be used in many ways as catalysts. To be able to tailor them in such a way that they can catalyse certain reactions selectively and efficiently, researchers need to determine the properties of single particles as precisely as possible. So far, an ensemble of many nanoparticles is analysed. However, the problem of these investigations is that the contributions of different particles interfere, so that the properties of individual particles remain concealed.
Researchers at Ruhr-Universität Bochum, the University of Duisburg-Essen and the Technical University of Munich describe a new method to observe single nanoparticles before, during and after an electrochemical reaction in the journal “Angewandte Chemie“ from 16 April 2019. “For this purpose, we have created the particle at the stick,“ explains Professor Wolfgang Schuhmann, head of the Center for Electrochemical Sciences.
Observing the complete lifecycle
The researchers grew a catalyst nanoparticle at the tip of a carbon nanoelectrode, subsequently activated it and used it to catalyse an electrochemical reaction. They analysed changes in its shape and chemical composition after each step.
The nanoparticle performed excellently and reached turnover rates, which are comparable to industrial electrolysis devices. “However, for us it was even more important to see that the nanoassembly of electrode and particle was stable enough for a follow-up examination after catalysis,” says Wolfgang Schuhmann.
Editor: Julia Weiler, julia.weiler@uv.rub.de
26th April 2019,
Chemistry.
© RUB, Marquard
Researchers have found the key to long life for bioelectrodes that convert sunlight into electricity.
Proteins involved in photosynthesis can be used to produce electricity from solar energy economically and efficiently. However, although these proteins, such as Photosystem I, are naturally robust, the lifespan of isolated protein complexes in semi-artificial electrodes is considerably shorter. Therefore, the technological application of such bioelectrodes is still limited. A research team at Ruhr-Universität Bochum has now shown that operation in an oxygen-free environment significantly extends the life of the bioelectrode.
The team led by Dr. Fangyuan Zhao, Dr. Adrian Ruff, Dr. Felipe Conzuelo and Prof. Dr. Wolfgang Schuhmann from the Centre for Electrochemistry and Prof. Dr. Matthias Rögner from the Department of Plant Biochemistry reported on their current research in the renowned "Journal of the American Chemical Society".
Oxygen is to blame
The researchers have already shown in previous studies that the operation of the bioelectrode produces reactive molecules that damage the Photosystem I and are responsible for the limited lifespan of the bioelectrode. These reactive species are produced by oxygen, which acts as an electron acceptor. "We have therefore proposed the design of bioelectrodes that operate in an oxygen-free environment," explains Felipe Conzuelo.
Step to application
Tests have now shown that the lifetime of the bioelectrodes under exclusion of oxygen increases significantly compared to operation under the influence of oxygen. "We have thus taken an important step towards the efficient development and later application of photobioelectrodes for energy conversion," says Fangyuan Zhao.
Editor: Meike Drießen Translation: Materials Chain
16th April 2019,
Award to be presented in October. Read original article
Suzana G. Fries heads the group of Computational Thermodynamics/CALPHAD at ICAMS.
https://www.iom3.org/news/2019/apr/16/2019-iom3-awards-announced
4th April 2019,
Information Technology.
© RUB, Kramer
So-called spin lasers have the potential to significantly accelerate data transmission in fiber optic cables. And they also consume considerably less energy.
RUB engineers have developed a new concept for ultra-fast data transfer via fiber optic cables. In conventional systems, a laser sends light signals through the cables, and the information is encoded in the modulation of the light intensity. Physical limits prevent this from happening much faster than with a frequency of 40 gigahertz. In the international top magazine "Nature" of April 3, 2019, a team from Bochum describes how frequencies of 200 gigahertz and more could be achieved with semiconductor technology. The researchers from the Department of Photonics and Terahertz Technology cooperated with colleagues from Ulm and Buffalo.
The Bochum concept could not only enable considerably faster data transmission, but also save energy. Conventional technology is extremely energy-hungry at high speeds. "Unless we change the technology, data transmission and the Internet will soon consume more energy than we currently produce on Earth," says Prof. Dr. Martin Hofmann. Together with private lecturer Dr. Nils Gerhardt and doctoral student Markus Lindemann, he is therefore researching an alternative technology.
Speed limit not yet reached
The trick: The Bochum researchers code the information not in the modulation of light intensity, but in the modulation of light polarization. They generate an oscillating circular light polarization in which the direction of oscillation is repeatedly reversed. "We have shown that this oscillation can take place at 200 gigahertz," describes Hofmann. "We do not know how much faster it can still become. We haven't found a theoretical limit yet."
Oscillation alone does not transport information, however, and polarization must be modulated for this to happen. Hofmann, Gerhardt and Lindemann have experimentally confirmed that this is possible in principle.
Special lasers required
In order to generate the oscillating polarization, special lasers are required in which a semiconductor crystal is bent in a certain way. In addition, the researchers have to inject electrons with aligned spin into the crystal. "The system is not yet ready to be used. A lot of technological optimization is required," summarizes Martin Hofmann, who together with his Bochum colleagues has already applied for a patent that could remove one of the hurdles. "With our work, which demonstrates the potential of spin lasers, we want to open up a new field of research," Hofmann continues.
Julia Weiler, julia.weiler@uv.rub.de
28th March 2019,
ERC Advanced Grant.
Prof. Dr. Wolfgang Schuhmann © RUB
Converting carbon dioxide or nitrogen oxides into useful or non-toxic substances is difficult. Wolfgang Schuhmann wants to find ways and is being supported by the EU.
Prof. Dr. Wolfgang Schuhmann wants to produce useful basic chemicals from harmful gases on an industrial scale using novel catalysts. For this project, the head of the Department of Analytical Chemistry at Ruhr-Universität Bochum will receive an Advanced Grant from the European Research Council (ERC). The grant amounts to 2.5 million euros over five years.
Reaction chain does not normally run according to plan
The electrochemical conversion of CO2 or nitrogen oxides into useful or non-toxic derivatives is based on a complex series of reactions. Some require more energy, others less. "Chemistry always opts for the most energy-efficient route," explains Wolfgang Schuhmann, member of the flagship program Materials Chain and the Ruhr Explores Solvation excellence cluster (Resolv). Therefore, the reaction chain does not run according to plan, and a wide variety of products are produced, not just the ones one would like.
In addition, CO2 is poorly soluble in liquids. Conventional electrochemical cells therefore cannot convert industrially significant amounts of CO2.
One point of contact for three phases
Special electrodes modified with catalysts, which Wolfgang Schuhmann plans to design in his ERC Grant, are intended to provide a remedy. The electrodes are based on a conductive fleece that is Teflon-coated on one side and is therefore not permeable to water but permeable to gas. Various catalyst particles are embedded in the fleece. While the gas enters the fleece from the watertight side, it is moistened from the other side. "This creates a place in the fleece where all three components - gas, liquid phase and catalyst - come into contact with each other," explains Schuhmann.
Particles of a certain order
Through a defined relative orientation of the various catalyst particles in these so-called gas diffusion electrodes, only the desired reactions are to take place in the desired sequence, so that the desired product is finally produced, for example harmless nitrogen from nitrogen oxide. All possible side paths of unwanted reactions are to be prevented in this way.
The aim of the ERC project is to understand the design of cooperating catalysts for selective cascade reactions and to demonstrate their function. The research focuses on the production of basic chemicals by CO2 reduction and air purification of nitrogen oxides.
27th February 2019,
Chemistry.
© Roberto Schirdewahn
So far, there has been no method to investigate the influence of the particles. First results with a new method show that the particles behave differently than expected.
Silver particles have an antibacterial and anti-inflammatory effect. For this reason, they are now widely used, for example as coatings for wound dressings, as odor inhibitors in sportswear or in food packaging. From there they are regularly released into the environment. "When sportswear is washed, 50 percent of the silver particles contained in it dissolve in water per wash," says Prof. Dr. Kristina Tschulik, a chemist in the Ruhr Explores Solvation Excellence Cluster at the RUB. "Ultimately, they land in the sea. What happens to them there is still largely unknown.
This is because the tiny particles, which are only a few nanometres in size, are difficult to examine - especially when they are present in low concentrations in a complicated environment such as seawater. "There are many sources of disturbance here, such as salts or algae," explains Tschulik. Conventional methods for the analysis of nanoparticles cannot cope with this because they usually work in a high vacuum.
Anti-breath odour spray under test
Kristina Tschulik's research group for electrochemistry and nanoscale materials has developed a new process that changes this. It can detect individual nanoparticles in solution and analyse what happens to them there. For this purpose, the scientists combined a previously established electrochemical process with a spectroscopic method.
In a first step, the researchers demonstrated that the method is robust against sources of interference by taking water samples from an untouched Canadian fjord. Although this water contained salts, algae and other disturbing factors, it did not contain any industrial impurities.
They bought a silver nanoparticle spray on the Internet, which was offered for the disinfection of cutlery and as a remedy for bad breath in dogs. They sprayed it into the fjord water and examined with the electrochemical method whether they could detect the particles. This succeeded.
Using the combined spectro-electrochemical method, they analysed in further studies what happens to silver particles in saline water. Previously, it was assumed that the particles were dissolved as silver ions in water.
Clumping of particles
This assumption was not confirmed; instead, the particles clumped and reacted to silver chloride. "So they would probably sink to the ground and sediment," concludes Tschulik. "They would then be removed from the seawater, but one would have to consider what long-term consequences these heavy metal deposits could have for sea dwellers living near the bottom.
Because there was no previous method for studying nanoparticles in natural environments, little is known about their impact on the environment. "Based on such a single result, one should not panic," says Kristina Tschulik, recalling that different nanoparticles can behave very differently - so one cannot draw conclusions about all nanoparticles from a few studies. But: "The more we use nanoparticles, the more important it is for us to be able to assess their effects," adds the researcher.
No obligation to monitor so far
With the Tschuliks group' method this would be possible - not only in sea water, but also, for example, in the process waste water of industrial companies. "As long as there are no established measurement methods and consequently no legal obligation to detect such particles, the companies will of course not do so", Tschulik knows. Should the legislator introduce such a control obligation, the basis for the construction of suitable sensors is now available.
Editor: Julia Weiler julia.weiler@uv.rub.de
27th February 2019,
Chemistry.
© Roberto Schirdewahn
Fuel cells do not yet function optimally because the perfect catalyst is missing - so far, the wrong methods have been used to find them, says Kristina Tschulik.
Prof. Dr. Kristina Tschulik's research objects are small. Very small. A thousand times smaller than the diameter of a human hair. These are nanoparticles that are produced in various forms and compositions and have become indispensable in industry. Catalysts for numerous reactions are produced in the form of nanoparticles. They consume little material but have a large surface on which the chemical reactions can take place.
An industrially produced batch of nanoparticles is a collection of many individuals that vary in shape, size and chemical composition. Kristina Tschulik is interested in each and every one of the tiny ones. With her team from the RUB Research Group for Electrochemistry and Nanoscale Materials, she characterizes individual particles and also determines which ones are particularly catalytically active.
"If one knew which properties make individual particles particularly active, it would be possible to specifically produce particles with precisely these properties," explains the chemist. Many promising technologies, such as fuel cells, do not yet work as desired because the optimal catalysts are lacking. "I think this is because we do not yet have the perfect methods to characterise the catalysts," says Tschulik.
Like in concert
The common methods are established for large electrodes. They provide an average value for an ensemble of nanoparticles. This would be sufficient if the particles were all the same, but they are not. "You have to imagine it as with people in a concert: One person sings on stage, everyone in the audience sings along," the Bochum researcher compares. "If we only hear the singing together, we won't find out who the star is - but that's exactly what we want to hear."
Since the nanoparticles are so small, they can only be made visible with special microscopes, usually in a high vacuum - in other words, under conditions that are virtually non-existent on Earth. The researchers around Kristina Tschulik have therefore developed a new method with which they can analyse the particles directly in solution. To be more precise, they combined an electrochemical with a spectroscopic method in order to be able to investigate different properties of the particles.
Two methods combined
The team uses an electrode as thin as a hair, applies a certain voltage to it and immerses it in a solution of particles. The so-called Brownian movement - a thermal movement that causes small particles in liquids and gases to jerk back and forth in an undirected direction - causes some of them to strike the electrode over time. If the voltage is selected correctly, these particles react on the electrode surface. Silver particles, for example, are converted into silver chloride or dissolved, depending on which substances the surrounding solution contains. Each time a silver atom reacts to form a single positively charged silver ion, an electron is released, which flows off as a current through the electrode. By measuring the current flow, the chemists can deduce the number of atoms that have reacted and thus the size of the particle. The method is so sensitive that it detects currents in the Piko ampere range (10-12 amps). Even particles 2 and 2.5 nanometers in diameter can be easily distinguished. The decisive factor for this electrochemical method is that the particles are present in the solution in low concentrations so that they strike the electrode individually.
This electrochemical method, which Kristina Tschulik helped to develop in Oxford from 2012, has now been brought together by her Bochum team with so-called dark-field microscopy. The latter allows the chemists to visualize the particles in real time as colored pixels. By changing the color of the dots, or more precisely by using the spectral information, they can track what happens to the particles on the electrode surface, for example, whether they dissolve or convert, for example into silver chloride.
Chemical nose with electricity meter
The spectro-electrochemical process is specific to a particular type of particle. Depending on the voltage applied to the electrode by the researchers, particles made of different materials react, for example silver particles at a lower voltage than gold particles. "We therefore have a chemical nose and a method that provides quantitative information about the current flow. This is very rare," sums up Tschulik. Scientists can also use the technology to observe whether particles clump together, i.e. when the particles hitting the electrode become larger over time.
This method enables Tschulik's team not only to determine the size of nanoparticles, but also how efficiently they work as catalysts. For this analysis, the scientists set the conditions so that the particles do not dissolve at the electrode surface but catalyze a chemical reaction there. The current flow tells them the conversion rate. In addition, they can monitor whether the activity of the ageing particle remains constant or decreases or even increases over time. After the analysis, they can observe the particle adhering to the electrode under the microscope and thus determine its shape.
Optimizing catalysts for energy technology
According to Kristina Tschulik, this effort for many individual particles is worthwhile: "The catalyst activity does not change linearly with the properties," she says. A particle that is half the size of another is not automatically half or twice as active. There are very complex and unpredictable relationships between the shape, size and composition of particles and their activity in catalysis. Every individual could therefore be a star.
Kristina Tschulik and her team now have a tool at hand with which they can search for these stars among the nanoparticles. They want to make their contribution to finding the optimal catalysts for fuel cells, the electrolysis of water and other technologies in the field of regenerative energy.
Editor: Julia Weiler, julia.weiler@uv.rub.de
25th February 2019,
Emmy Noether Group for Physicist.
© private
Generating electricity from heat differences or mechanical energy has been possible for a long time. But the materials required are usually expensive, rare or toxic. Physicist Dr. Anna Grünebohm from the University of Duisburg-Essen (UDE) researches harmless and easily available alternatives. She has succeeded in recruiting one of the coveted Emmy Noether junior research groups, and will be funded with more than €1.3 million for six years.
The material class Grünebohm works with is oxides with a perovskite structure. That sounds complicated but it can simply be imagined as a Lego kit: the underlying crystal structure remains the same, but individual atoms can be exchanged and properties can be specifically designed.
Many of these materials can be electrically polarized permanently and also have other properties that make them promising candidates for sustainable technologies: For efficient cooling with electricity, the use of waste heat or the short-term storage of electrical energy, to name just a few examples.
But the necessary features are sometimes difficult to set as a combination: "The greatest temperature changes possible, for example, often occur at more than 100°C and in thin films. For many cooling applications, however, one would like to reach room temperature. In addition, you need more material for a large cooling capacity, so that you cannot work with the ideal thin layers," Grünebohm explains. With homogeneous materials, this tightrope walk is difficult to impossible.
In her working group "Scale-bridging computational design of multifunctional ferroelectric composites", the 35-year-old therefore researches nanomaterials consisting of thin layers with a thickness of just a few atoms or materials containing tiny inclusions. Not only can the different properties of the subsystems be combined in a completely new way, the interfaces also provide exciting new functionalities.
Grünebohm's field is theoretical physics; it works with simulations that have great predictive power. To put it simply, she can use the computer to design an ideal material that will later serve as a blueprint for other scientists. In spring, her group will start with two PhD students within the "Materials Chain" flagship program of the University Alliance Ruhr.
The Emmy Noether Program of the German Research Foundation (DFG) enables up-and-coming young scientists to qualify for a professorship by leading a junior research group.
Further information:
Dr. Anna Grünebohm, +49 203 37-94271, anna@thp.uni-due.de
Editor: Birte Vierjahn, + 49 203 37-98176, birte.vierjahn@uni-due.de
21st February 2019,
UA Ruhr Deepens Cooperation with Brazil.
© UDE
Brazil is the destination of a UDE working group on inorganic chemistry. With the support of the UA Ruhr Liaison Office Latin America, they will meet with colleagues at the University of São Paulo (USP) at the end of February. One of their projects is to investigate the biomedical applications of metallic nanoparticles.
Prof. Matthias Epple and Dr. Oleg Prymak have maintained close working contacts with Prof. Cristiano Luiz Pinto de Oliveira at the USP for many years. Their pioneering projects are financed by German and Brazilian funding institutions, including the current workshop "Materials science addressed with modern analytical and theoretical methods". Participants from Argentina and Uruguay are also expected. A three-day summer school on "Metallic Nanoparticles: synthesis, characterization and applications" is also planned.
The UDE delegation's trip to Brazil also serves to intensify working contacts at the Federal University UFABC, the UA Ruhr's strategic partner in Brazil. Prof. Epple and Dr. Prymak, together with their partners Prof. Iseli Lourenço Nantes and Prof. Fabio Furlan Ferreira, are developing joint projects in the bionanosciences. They are also involved in the UFABC Germany Day.
Further information:
Inorganic Chemistry, Prof. Dr. Matthias Epple, Tel. 0201/18 3-2413, matthias.epple@uni-due.de
Dr. Oleg Prymak, Tel. 0201/18 3-2401, oleg.prymak@uni-due.de
Editor: Beate Kostka, Tel. 0203/37 9-2430, beate.kostka@uni-due.de
8th February 2019,
4 Million Euros for Microelectronics Laboratory.
Professors Nils Weimann (l.) and Andreas Stöhr (r.) with Christian Blumberg at a semiconductor integration facility. This is located in the clean room of the University's Center for Semiconductor Technology and Optoelectronics. © UDE
An animal jumps onto the road. It is pitch-black and foggy, but the automotive car brakes safely. One of the sticking points in autonomous driving is that such an environment recognition system works flawlessly. New sensors based on high-frequency radiation could be the solution. In the future, they will be developed at the University of Duisburg-Essen (UDE). To this end, the Federal Ministry of Education and Research is financing the expansion of a microelectronics laboratory with almost four million euros.
Electronic and photonic chips can be used to determine objects and measure their position, distances and speeds. We know this from driver assistance systems, but also from industry. Thanks to them, robots pick the right parts from unsorted crates and act independently next to people. However, today's sensors for environment recognition have their limits, for example in the case of concealed vision. They also do not yet work with the required accuracy.
UDE professors Dr. Nils Weimann, Dr. Andreas Stöhr and Dr. Thomas Kaiser are therefore researching innovative transistors and infrared components. Their new "ForLab SmartBeam" laboratory is located at the Center for Semiconductor Technology and Optoelectronics (ZHO), which already has a first-class infrastructure. With the 3.95 million euros from Berlin, two high-quality systems and instruments for high-frequency measurement up to 1.5 terahertz are now being purchased.
Terahertz sensors
This electromagnetic spectrum is interesting for many applications. Between 300 gigahertz and a few terahertz, the waves penetrate through material and organic tissue safely for humans. Ideal for detecting toxic substances or hidden objects. However, terahertz sensors are not yet suitable for mass production - the necessary chips require a special semiconductor material: indium phosphide. In this material, the electrons can move faster than in the commonly used silicon. It is also suitable for the manufacture of efficient opto-electronic terahertz components. The required technologies are researched and developed at the ZHO of the university.
Not only the three professors are sure that the fast waves have great potential for the automotive industry, mechanical engineering, medical technology or telecommunications. The German Research Foundation is also pushing development further in that area via the Collaborative Research Centre MARIE. It deals with mobile terahertz applications and is headed by the UDE.
Further information: Prof. Dr. Nils Weimann, Components of Highest Frequency Electronics, Tel. 0203/37-93391, nils.weimann@uni-due.de
Editor: Ulrike Bohnsack, Tel.: 0203/37-92429, ulrike.bohnsack@uni-due.de
5th February 2019,
Materials Science.
© RUB, Marquard
The days of handwritten records are over at the Chair of Materials in Microtechnology. This makes new research approaches possible.
Every research experiment has to be documented, only in this way the results can be evaluated, checked and reproduced. This documentation may be self-evident, but as always the devil is in the detail. Different people document with different systematics, often still handwritten in a laboratory book, which is more or less readable for the colleagues. Anyone who wants to find certain information in such records after years needs patience.
Many advantages
This is no longer the case at the Chair of Materials in Microtechnology. Prof. Dr. Alfred Ludwig's group has set up a digital data management system that bundles all the information that accumulates at the chair. Not only manuals for measuring instruments, publications, lectures and software scripts are stored here. The team also feeds the data generated in all research projects into the system. This is done in a standardized form that is also comprehensible and searchable for colleagues. "Each physical sample receives a digital twin from us," explains Alfred Ludwig. The samples in the archive can be clearly assigned to the data in the system via an ID. The goal: more efficient research.
For each sample, the team can see at the touch of a button how it was produced, which raw data was collected during the measurements and how the data was processed further. External inquiries about samples can thus be answered quickly and easily. And there are other advantages: "In research, we have relatively short personnel cycles. If an employee leaves and a new one arrives, he should be able to continue working as seamlessly as possible - this now works with our data management system," explains doctoral student Lars Banko, who designed the system and put it into practice. The materials scientists use adaptable commercial software that they have continuously adapted to their needs in recent years.
Connecting measuring instruments with a database
Initially, the team, of which Dr. Sigurd Thienhaus is a member, developed uniform standards for data collection. This enables the researchers to easily use measurement results from various experiments for comprehensive analyses. At present, the values still have to be entered into the program. In the future, as many measuring instruments as possible will be directly connected to the software and will feed the data independently. The Center for Interfacial-Dominated High-Performance Materials (Zentrum für Grenzflächendominierte Höchstleistungswerkstoffe - ZGH) will also use the software in the future.
This approach enables new analyses. Values from different experiments can be summarised and evaluated using machine learning methods. The first analyses of this kind are already being carried out at the Chair of Materials in Microtechnology. "We want to learn from previous measurements how we can carry out future experiments more efficiently," explains Alfred Ludwig. "For example, we can determine whether we should glow a sample at 300 or 700 degrees Celsius. But the methods also help us to find relationships in the data that we would otherwise probably never have noticed.
The group also plans to use virtual and augmented reality to better visualize the complex data.
The researchers concluded that the work they put into the data management system was worthwhile for them. One day, they hope, similar systems in other groups at the RUB could help to further intensify interdisciplinary cooperation.
Editor: Julia Weiler julia.weiler@uv.rub.de
31st January 2019,
Research Project.
© RUB, Marquard
Producing such thin metal layers is like putting a flea on the top of Cologne Cathedral. With a modern method and new chemistry it should nevertheless succeed.
Researchers at the Bergische Universität Wuppertal and the RUB want to develop a new process for the production of transparent ultra-thin metal layers. The metal films could be used as transparent contact layers for solar cells and light-emitting diodes. The German Research Foundation is funding the project with 600,000 euros for three years. Prof. Dr. Thomas Riedl from the Wuppertal Chair of Electronic Components is leading the project together with Materials Chain Member Prof. Dr. Anjana Devi from the Bochum research group Chemistry of Inorganic Materials.
Solar cells and light-emitting diodes require electrical contact layers, the electrodes, to operate. At least one of the electrodes must not only be conductive, but also partially translucent in order to guarantee high efficiency. Particularly thin metal films can meet these requirements. However, they must not be thicker than ten nanometers. "In size comparison with the carrier material on which this layer is usually applied, this corresponds roughly to a flea sitting on the tip of Cologne Cathedral," explains Thomas Riedl.
A single layer of atoms
In the new project, the scientists want to use atomic layer deposition, ALD for short, to produce the metal films. The process enables them to coat large surfaces evenly, even if the layers have the thickness of a single layer of atoms. ALD is already industrially established for the production of ceramic thin films, but not yet for metals such as silver and copper. In preliminary work, the team from the Chair of Electronic Devices at Bergische Universität has developed a system prototype for plasma-assisted spatial sequential ALD at atmospheric pressure.
New chemical precursors needed
The chemical precursor molecules required for ALD pose a major challenge. "These have to be thermally stable, have a high vapour pressure and, in combination with a suitable reaction partner, convert completely into a metal film at low temperatures," says Nils Boysen, PhD student in the RUB's Chemistry of Inorganic Materials group. The group is one of the world leaders in the development and synthesis of precursor molecules.
"Only a few chemical precursors are known for the ALD of metallic thin films," explains Anjana Devi. "We want to develop new suitable precursors to successfully deposit metallic thin films."
The close cooperation between the two working groups led to a publication in the journal Angewandte Chemie even before the project was approved for funding, thus laying the foundation for the research project and further results.
Editor: Julia Weiler julia.weiler@uv.rub.de
28th January 2019,
Prof. Dr. Corina Andronescu is New at the UDE.
© UDE
While politicians are struggling for mandatory solutions to limit carbon dioxide (CO2) emissions, Dr Corina Andronescu is researching a complementary solution – the electrochemical conversion of CO2 into usable fuels such as methanol, called "Dream Reaction". In December, she was appointed junior professor for electrochemical catalysis at the University of Duisburg-Essen (UDE).
It would indeed be a "dream reaction" to either permanently store the climate-damaging gas or convert it into something useful. And it would be an approach to counteracting global warming. Another approach is electrocatalytic water splitting, which produces hydrogen. This universal energy store can be used, for example, to power vehicles. Both processes are based on electrocatalysis, the core of Andronescu's research. Her goal is to develop catalysts that are stable over the long term while maintaining high electrical conductivity. To this end, she embeds the catalyst material as nanoparticles in carbon lattice structures.
At the UDE, she will be located both at the NanoEnergieTechnikZentrum (NETZ) and the Zentrum für BrennstoffzellenTechnik (ZBT) and set up a laboratory for electrochemistry. "It is a great opportunity to be in direct touch with colleagues who produce suitable materials for this purpose.”
Even before her appointment, the Romanian-born scientist conducted research at the university alliance UA Ruhr: She was head of her own research group on the subject at the Center for Electrochemical Science at the Ruhr University in Bochum. As a postdoctoral student, she previously worked on materials for biosensors and coatings at the Polytechnic University of Bucharest, where she completed her master's degree in 2011 and her doctorate in 2014. Since 2017, she has co-invented a patent application for self-healing nanoparticle-based catalyst layers for electrocatalysis.
Andronescu's professorship is part of the Federal Government's programme for the promotion of young scientists (WISNA), which aims to offer young scientists a transparent and predictable path to a professorship for life. To date, 468 of these tenure-track professorships have been funded throughout Germany, 21 of them at the UDE.
Further Information: Prof. Dr. Corina Andronescu, corina.andronescu@uni-due.de
Editor: Birte Vierjahn, +49 203 37-98176, birte.vierjahn@uni-due.de
17th January 2019,
Prof. Dr. Doris Segets is new at the UDE.
© UDE
Solar and fuel cells, LEDs, batteries – many sustainable technologies already contain nanoparticles. But still there are hardly any scalable processes for the production in industrial dimensions. That’s what Prof. Dr. Doris Segets wants to change. She took up the professorship for “Process Engineering of Electrochemical Functional Materials” at the University of Duisburg-Essen (UDE). Already, she has been appointed to the board of directors of the NanoEnergieTechnikZentrum (NETZ).
Whilst nowadays nanoparticles can be produced in large quantities, there is still a lack of suitable processing methods for industrial production. In order to get closer to this aim, Segets first wants to clarify some basic issues: For example, by analyzing the properties of the particles she means to understand how they behave in contact with certain liquids. If she succeeds in distributing the particles evenly in the solvent, the result will be an ink that can be used to print structured, functional layers for numerous applications.
At the UDE, Segets will be performing her research both at the NETZ and at The Hydrogen and Fuel Cell Center (ZBT). For her, a matter of particular interest will be the "linked facilities" in the NETZ: These laboratories are directly connected to the large synthesis plants for nanomaterials. "One of my objectives is to characterize the layers generated from the particles online", the 36-year-old explains. "Along with our colleagues from the synthesis department, we could understand and improve the entire process chain from the production of nanomaterials to the finished layer for batteries or fuel cells.”
Before joining the UDE, Segets worked at the Friedrich-Alexander-University Erlangen-Nuremberg. There, she studied “Chemical and Biological Engineering”, received her doctor’s degree in 2013 and subsequently was head of the "Nanoparticle Processing" working group as a postdoc. For the research that she performed here she was awarded the Friedrich Löffler Prize – one of the most important prizes for young engineers in particle technology. Over and above, between 2015 and 2018, she was also scientific coordinator of the Interdisciplinary Center for Functional Particle Systems.
Her appointment to the board of directors reveals that she is already deeply involved in research at her new workplace. Here, she succeeds Dr. Ekaterina Nannen, who was appointed to a professorship at the Hochschule Niederrhein in autumn 2018.
Segets' professorship is part of the national grant program for the promotion of young scientists (WISNA), which aims to offer young researchers a transparent and predictable path to a professorship for life. To date, 468 of these tenure-track professorships have been funded throughout Germany, 21 of them at the UDE.
Further Information: Prof. Doris Segets, Process Technology for Electrochemical Functional Materials, +49 203 37-98230, doris.segets@uni-due.de
Editor: Birte Vierjahn, +49 203 37-98176, birte.vierjahn@uni-due.de
16th January 2019,
Does gold increase the radiation effect?.
© Pixabay
A research consortium will receive 810,000€ from the "LifeSciences.NRW" lead market competition to develop new approaches for treating children with brain tumours better in the future. The project is led by Prof. Dr. Beate Timmermann, Director of the Clinic for Particle Therapy at the Faculty of Medicine of the University of Duisburg-Essen (UDE) and Medical Director of the West German Proton Therapy Centre (WPE) at Essen University Hospital.
If tumors are specifically irradiated with protons, surrounding healthy tissue can be spared. "This is particularly important for young children who need intensive treatment because of a brain tumour, but whose whole body is still growing," says Prof. Timmermann. The funds will be used to develop a new therapeutic approach (SYNGOPRO) in which proton radiation is combined with locally administered gold nanoparticles.
"There are indications that gold nanoparticles increase the radiation effect. In this case, the healthy tissue could be spared if it were possible to specifically amplify the radiation where it is supposed to have an effect," says Materials Chain member Prof. Dr. Stephan Barcikowski from the Center for Nanointegration Duisburg-Essen (CENIDE). Now it is important to transfer the promising results from the preliminary investigations into everyday clinical practice.
"In order to optimise the effect of the tiny particles in the irradiation of tumours, we need good preclinical models, which we will develop in SYNGOPRO," explains Prof. Dr. Alexander Schramm, head of the Laboratory for Molecular Oncology." Dr. Stephan Tippelt, senior physician at the Children's Hospital III at the University Hospital in Essen and a specialist in brain tumours, confirms: "We want to find out whether and to what extent the particles intensify the irradiation effect."
In the long term, it might then be possible to reduce the amount of radiation to a minimum, which would of course be even more tolerable for the children. Radiation always entails a certain risk of undesired side effects. If radiation therapy can be conducted with lower doses because the effect has been increased thanks to the corresponding nanoparticles, possible late effects from radiation can be avoided and the quality of life of the young patients can be improved.
The project is also an important step towards the rapid transfer of new research results to everyday clinical practice. This is made possible by special expertise in all relevant disciplines, such as paediatric neurooncology, neurosurgery, neuropathology as well as radiation/proton therapy at the University Hospital Essen and in close cooperation with the scientific partners at the UDE.
The project was funded by the European Regional Development Fund (ERDF).
Further information:
https://www.leitmarktagentur.nrw/aktuelles?cmd=showDetail&id=109
Synergistic effects of gold nanoparticles and proton radiation in the treatment of childhood brain tumors, SYNGOPRO
Editor: Christine Harrell, Faculty of Medicine, Tel. 0201/723-1615, christine.harrell@uk-essen.de
8th January 2019,
Inverse magnetocaloric effect.
© TUBITAK
Dr. Mehmet Acet has been awarded the most prestigious Turkish science prize for his "pioneering work on the inverse magnetocaloric effect".
The physicist from the AG Farle (UDE) received the Special Award for his outstanding work on an international level, endowed with around 12,000 €, on December 26th in Ankara. The prize is awarded annually by the Scientific and Technological Research Council of Turkey (TUBITAK).
Further information: Dr. Mehmet Acet, 0203 37-92023, mehmet.acet@uni-due.de
Editor: Birte Vierjahn, 0203 37-98176, birte.vierjahn@uni-due.de
17th December 2018,
UA Ruhr-Professorship: Joint Platform for Catalysis Research.
© UDE
The University Alliance Ruhr (UA Ruhr) continues to grow together: Prof. Dr. Malte Behrens will teach and conduct research at the University of Duisburg-Essen (UDE) and at Ruhr-University Bochum (RUB) over the next four years as UA Ruhr Professor for Material Chemistry of Catalysts.
The UDE chemist is already speaker of a joint Collaborative Research Centre (CRC) with RUB and now the fourth cross-location UA Ruhr professor. The Mercator Research Center Ruhr (MERCUR) is funding the project with one million euros.
Catalysts enable chemical reactions to be carried out more efficiently: For example, they enable environmental pollutants to be broken down more quickly or chemical products to be produced in a more resource-efficient way. Prof. Behrens: "They play an important role as 'marriage mediators' between molecules that without them would either not find each other at all or would only find each other very slowly." However, it is still relatively unexplored how the surface of metal oxides changes. They are economically very important, for example for the production of basic and specialty chemicals.
The aim of the UA Ruhr professorship is therefore to develop, investigate and understand new catalysts for such oxidation reactions. This topic forms a relevant interface between materials science and chemistry: "For a better understanding of the complex chemical basics, an interdisciplinary approach is required that combines inorganic, physical and technical chemistry as well as aspects of physics and engineering sciences," says Prof. Behrens.
This interdisciplinary cooperation is already being implemented in the joint CRC "Oxidation Catalysis in the Liquid Phase". It brings together 23 research groups with the participation of the Max-Planck-Institutes in Mülheim and the Fritz-Haber-Institute in Berlin. The projects of the new UA Ruhr Professorship are a targeted extension of this collaborative research. Additionally, the UA Ruhr flagship program Materials Chain and the UDE research centres Center for Nanointegration (CENIDE) and Center for Water and Environmental Research (ZWU) will also benefit from this.
Prof. Behrens: "Because catalysts can change significantly under reaction conditions, we will focus primarily on Raman spectroscopy under the umbrella of the UA Ruhr Professorship in order to decipher the function of the catalysts during operation. To this end, we are setting up a special spectroscopy laboratory at Ruhr-University Bochum, new synthesis and catalyst laboratories at the NanoEnergieTechnikZentrum NETZ of the UDE and a laboratory for photocatalysis in aqueous solutions at the future Future Water Campus of the UDE."
Further information:
http://www.uaruhr.de/forschung/
https://www.uni-due.de/2018-05-18-neuer-sfb-katalyse
https://www.uni-due.de/2018-04-23-future-water-campus
The University Alliance Ruhr
Since 2007, the three universities in the Ruhr Area have been working closely together strategically under the umbrella of the University Alliance Ruhr (UA Ruhr). By joining forces, the services of the partner universities are systematically expanded. Under the motto "better together", there are now more than 100 cooperations in research, teaching and administration. With more than 120,000 students and almost 1,300 professors, the UA Ruhr is one of Germany's largest and most efficient science locations.
Further information: http://www.uaruhr.de/
Mercator Research Center Ruhr
Founded in 2010, the Mercator Research Center Ruhr (MERCUR) promotes cooperation between the Ruhr-University Bochum, the TU Dortmund University and the University of Duisburg-Essen, which have been affiliated in the University Alliance Ruhr (UA Ruhr) since 2007. With its programme lines, MERCUR supports scientists, institutes, faculties and the administrations of the three universities in networking across universities, especially in research, but also in teaching and university management. In addition, MERCUR initiates projects in the region with the aim of improving the framework conditions for science in the Ruhr Area and promoting its exchange with industry and politics.
Further information: http://www.mercur-research.de
Redaktion: Beate Kostka, Tel. 0203/379-2430, beate.kostka@uni-due.de
17th December 2018,
CRC TRR 247 successfully started. Read original article
During the kick-off meeting of the Collaborative Research Centre / Transregio (CRC TRR) 247 on December 4th and 5th at the NanoEnergieTechnikZentrum NETZ, the scientists were already willing to dig in: 74 researchers – from group leaders to young scientists – presented their first results on different catalytic material systems.
The interdisciplinary cooperation in the joint CRC TRR "Oxidation Catalysis in the Liquid Phase" at the University of Duisburg-Essen (UDE) and the Ruhr-University Bochum (RUB) is a decisive factor for success. The CRC TRR 247 brings together 23 research groups, among them the Max Planck Institutes in Mülheim and the Fritz Haber Institute in Berlin. The scientists want to fundamentally understand oxidation catalysis – both its reaction mechanisms and the structure of the catalytically active centres. The projects of the associated new UA Ruhr professorship are a concerted extension of this collaborative research. The UA Ruhr flagship program Materials Chain and the UDE research centres Center for Nanointegration (CENIDE) and Center for Water and Environmental Research (ZWU) will also benefit from this.
"Since catalysts can change significantly under reaction conditions, under the umbrella of the UA Ruhr professorship we will focus primarily on Raman spectroscopy in order to decipher the function of the catalysts during operation. To this end, we are setting up a special spectroscopy laboratory at the RUB, new synthesis and catalyst laboratories at the NanoEnergieTechnikZentrum NETZ of the UDE and a laboratory for photocatalysis in aqueous solutions at the projected Future Water Campus of the UDE”, explains Prof. Malte Behrens, who will hold the UA Ruhr professorship for Materials Chemistry of Catalysts at the UDE and the RUB for the next four years.
During the kick-off meeting, it quickly became clear that networking among the subprojects and between theorists and practitioners is working well: Every 15-minute presentation of each subproject was followed by an equally long and fruitful discussion.
The next joint workshop of the CRC TRR 247 will take place in September 2019.
Further information: Dr. Franziska Günther, 0203 37-98171, info@sfbtrr247.uni-due.de
7th December 2018,
How Ice Particles Promote the Formation of Radicals.
© RUB/Marquard
The production of chlorofluorocarbons, which damage the ozone layer, has been banned as far as possible. However, other substances can also tear holes in the ozone layer in connection with ice particles such as those found in clouds. Researchers at the Ruhr-University Bochum, the University of Duisburg-Essen and the Friedrich Alexander University Erlangen-Nuremberg have uncovered a possible mechanism for this. They describe it in the journal "Physical Review Letters" of 13 November 2018.
The work was based on many years of cooperation between the Bochum, Duisburg-Essen and Erlangen-Nuremberg teams led by Prof. Dr. Karina Morgenstern, Dr. Cord Bertram, Prof. Dr. Uwe Bovensiepen and Prof. Dr. Michel Bockstedte, which is currently being continued within the framework of the Ruhr Explores Solvation (Resolv) excellence cluster.
Organic molecules are deposited in ice particles
Chemical processes can significantly influence the weather, the climate and the composition of the atmosphere. Cosmic rays or UV light provide the energy to split chemical compounds. In the case of bromine, chlorine or fluorine compounds, radicals, i.e. particularly reactive molecules, are formed. These attack the ozone molecules and can trigger chain reactions in the ozone layer. An earlier laboratory study had shown that ice particles with a silver core can promote such reactions. The team investigated the mechanism behind this in the current study.
In the laboratory, the scientists produced tiny ice particles and analysed how certain compounds containing chlorine or bromine interacted with them. They condensed the ice particles onto copper. In nature, mineral dust particles form condensation nuclei for the ice particles.
Using microscopic and spectroscopic methods, they observed that the molecules preferentially attached themselves to defects in the ice structure. The surrounding water molecules of the ice structure then reoriented themselves; they hydrogenated the molecules. This in turn made it easier to ionize the molecules in the experiment.
UV radiation generates radicals
The researchers irradiated the ice crystals with the attached molecules with UV light, which excited electrons in the ice particles in the vicinity of the molecules. These excited electrons ionized the chlorine and bromobenzene molecules. Through ionization, the molecules disintegrated into organic residues and highly reactive chlorine and bromine radicals.
"The mechanism could explain what happens when UV light hits mineral-contaminated ice," says Cord Bertram. "Thus, our results could help to understand the fundamental processes behind phenomena such as ozone holes.
The work was supported by the Deutsche Forschungsgemeinschaft within the framework of the Cluster of Excellence Resolv (EXC1069) and the projects BO1841/3-1, BO1823/5-1 and MO960/18-1. Computer simulations were carried out at the Forschungszentrum Jülich and at the HPC cluster of the regional computer centre Erlangen of the Friedrich-Alexander-University Erlangen-Nuremberg.
The University Alliance Ruhr
Since 2007, the three Ruhr universities have been working closely together strategically under the umbrella of the University Alliance Ruhr (UA Ruhr). By joining forces, the services of the partner universities are systematically expanded. Under the motto "better together", there are now more than 100 cooperations in research, teaching and administration. With more than 120,000 students and almost 1,300 professors, the UA Ruhr is one of Germany's largest and most efficient science locations.
Original publication
Philipp Auburger, Ishita Kemeny, Cord Bertram, Manuel Ligges, Michel Bockstedte, Uwe Bovensiepen, Karina Morgenstern: Microscopic insight into electron-induced dissociation of aromatic molecules on ice, in: Physical Review Letters, 2018, DOI: 10.1103/PhysRevLett.121.206001
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.121.206001
Further information:
Prof. Dr. Karina Morgenstern, Chair of Physical Chemistry I, Faculty of Chemistry and Biochemistry, Ruhr-Universität Bochum, Tel. 0234/32-25283, karina.morgenstern@rub.de
Dr. Cord Bertram, Experimental Physics: Ultrafast Dynamics at Interfaces, Faculty of Physics, University of Duisburg-Essen, Tel. 0203/379-4568, cord.bertram@uni-due.de
4th December 2018,
Humboldt Scholar in Organic Chemistry.
© privat
Dr. Suman Kumar Maity (31) is working on new organic-chemical compounds that are used in chemotherapy. The Humboldt Fellow is currently a guest of Prof. Dr. Carsten Schmuck in Organic Chemistry at the University of Duisburg-Essen (UDE).
Over the next two years, the scientist from Calcutta will focus on the development of self-organizing amino acids (peptides). They are only intended to attack tumour cells and overcome their cell walls. "The compound is slowly cleaved in order to better distribute the drug in the cell. This in turn increases the effect of chemotherapy," says Maity. At the same time, the toxic substances are reduced so that the cell-damaging substances are better tolerated.
Dr. Maity feels in good hands with Prof. Schmuck. Here, Dr. Maity is able to investigate the self-organising peptides in biological contexts. His research spectrum at the University of Calcutta is extensive, where he also deals with functional materials such as halogen ribbons or different light sources.
Further Information:
Dr. Suman Kumar Maity, sumankrmaity@gmail.com
Prof. Dr. Carsten Schmuck, Fakultät für Chemie, Tel. 0201/183-3097, carsten.schmuck@uni-due.de
Editor: Alexandra Nießen, Tel. 0203/379-1487
23rd November 2018,
Materials Chain at the 8th NRW Nano Conference. Read original article
© CENIDE
The 8th NRW Nano Conference took place on November 21 and 22 in the Congress Centre of the Westfalenhallen Dortmund. At its stand, Materials Chain displayed colorful nanoparticles, dazzling artificial opals and smooth-running rotors – only a few examples of its broad range of research.
This year's topic of the NRW Nano Conference, innovations in materials and applications, exactly matched the core competence of the UA Ruhr flagship program Materials Chain, which connects the material science departments of the three Ruhr universities. In order to demonstrate this union, the Materials Chain members of the Ruhr-Universität Bochum, the TU Dortmund University and the University of Duisburg-Essen organized a joint exhibition stand that showcased the broad range of materials sciences. The exhibits came from a variety of departments and varied from nanotechnology to various coating techniques to steel construction. These hands-on examples often led to fruitful conversations: For example, the replica of a screw rotor compressor whose screws, coated with tungsten carbide carbon, can be turned very smoothly, quickly brought the conference visitors into conversation with the coordinators of the profile focus. The vivid interest in the topics of the Materials Chain as well as the following exchange of contact information should lead to future cooperation and can be considered an indicator for a very positive conclusion of the event. Groups of students were particularly attracted by the colourful nanoparticles in colloidal form as well as by natural objects such as the dazzling Haliotis, which are a bionic model for research. Their curiosity and interest in general suggests, that the Materials Chain will continue to grow thanks to the next generation of young scientists.
Editor: Alexander Heinemann, 0203 379-8180, alexander.heinemann@uni-due.de
20th November 2018,
Prof. Dr. Karsten Seidl is new at the UDE.
© UDE
Dr. Karsten Seidl (36) is the new head of the Micro- and Nanosystems Department at the Fraunhofer Institute for Microelectronic Circuits and Systems (IMS). He has accepted the professorship of the same name for medical technology at the Faculty of Engineering at the University of Duisburg-Essen (UDE).
His research focuses on the smallest intelligent implants for the eye, brain and heart. These include so-called bio-sensor systems that check how the organs work and when they need to be supported. A further focus is bio-nanosensor technology, with which the DNA of cancer cells can be analysed and individual therapies implemented.
Prof. Seidl: "As a UDE professor, I also head a department at the Fraunhofer Institute in Duisburg, which offers great opportunities to advance the research of new technologies and systems to application maturity. In this way, small and medium-sized companies in the region can also benefit from our innovations." Another of Prof. Seidl's goals is to expand the Bachelor's and Master's courses in medical technology.
He knows his way around (bio)medical technology: For his diploma (2004/05) at Johns Hopkins University, USA, Seidl developed a sensor that measures the penetration depth of surgical needles in prostate cancer operations. He received his doctorate at the University of Freiburg with an excellent thesis on neuroimplants (2006 to 2011), which measure brain signals and release drugs where they are needed in the body. Starting in 2012, as a project manager in industry, he developed molecular diagnostic systems (lab-on-chip) with which the smallest amounts of fluids can be analysed completely and automatically.
Further information:
Prof. Dr.-Ing. Karsten Seidl, karsten.seidl@uni-due.de
Editor: Dr. Alexandra Nießen
20th November 2018,
Chemistry.
© RUB Marquard
So far, there has been no method to investigate the influence of the particles. First results with a new method show that the particles behave differently than expected.
Silver particles have an antibacterial and anti-inflammatory effect. For this reason, they are now widely used, for example as coatings for wound dressings, as odor inhibitors in sportswear or in food packaging. From there they are regularly released into the environment. "When sportswear is washed, 50 percent of the silver particles contained in it dissolve in water per wash," says Prof. Dr. Kristina Tschulik, a chemist in the Ruhr Explores Solvation Excellence Cluster at the RUB. "Ultimately, they land in the sea. What happens to them there is still largely unknown.
This is because the tiny particles, which are only a few nanometres in size, are difficult to examine - especially when they are present in low concentrations in a complicated environment such as seawater. "There are many sources of disturbance here, such as salts or algae," explains Tschulik. Conventional methods for the analysis of nanoparticles cannot cope with this because they usually work in a high vacuum.
Anti-breath odour spray under test
Kristina Tschulik's research group for electrochemistry and nanoscale materials has developed a new process that changes this. It can detect individual nanoparticles in solution and analyse what happens to them there. For this purpose, the scientists combined a previously established electrochemical process with a spectroscopic method.
In a first step, the researchers demonstrated that the method is robust against sources of interference by taking water samples from an untouched Canadian fjord. Although this water contained salts, algae and other disturbing factors, it did not contain any industrial impurities.
They bought a silver nanoparticle spray on the Internet, which was offered for the disinfection of cutlery and as a remedy for bad breath in dogs. They sprayed it into the fjord water and examined with the electrochemical method whether they could detect the particles. This succeeded.
Using the combined spectro-electrochemical method, they analysed in further studies what happens to silver particles in saline water. Previously, it was assumed that the particles were dissolved as silver ions in water.
Clumping of particles
This assumption was not confirmed; instead, the particles clumped and reacted to silver chloride. "So they would probably sink to the ground and sediment," concludes Tschulik. "They would then be removed from the seawater, but one would have to consider what long-term consequences these heavy metal deposits could have for sea dwellers living near the bottom.
Because there was no previous method for studying nanoparticles in natural environments, little is known about their impact on the environment. "Based on such a single result, one should not panic," says Kristina Tschulik, recalling that different nanoparticles can behave very differently - so one cannot draw conclusions about all nanoparticles from a few studies. But: "The more we use nanoparticles, the more important it is for us to be able to assess their effects," adds the researcher.
No obligation to monitor so far
With the Tschuliks group' method this would be possible - not only in sea water, but also, for example, in the process waste water of industrial companies. "As long as there are no established measurement methods and consequently no legal obligation to detect such particles, the companies will of course not do so", Tschulik knows. Should the legislator introduce such a control obligation, the basis for the construction of suitable sensors is now available.
Editor: Julia Weiler julia.weiler@uv.rub.de
16th November 2018,
Chemistry.
© RUB, Marquard
Actually, it is a catalyst for hydrogen production. But with a few tricks it can also take on other tasks.
If carbon dioxide could be converted into raw materials for the chemical industry, it would have killed two birds with one stone: keeping the climate-damaging gas out of the atmosphere and producing raw materials. The mineral pentlandite could help, as RUB researchers report with colleagues from Berlin and Fraunhofer Umsicht in the journal "Chemical Science" of November 5, 2018.
Until now, pentlandite was known as a catalyst for hydrogen production. However, scientists led by Dr. Ulf-Peter Apfel from the Chair of Inorganic Chemistry I converted it into a catalyst for CO2 recycling. They converted carbon dioxide into carbon monoxide, which is a common raw material for the chemical industry.
Solvents decisive
The decisive factor was the choice of a suitable solvent. Depending on the water content, the reaction produced either hydrogen or carbon monoxide. By precisely adjusting the water content, the researchers were also able to produce mixtures of carbon monoxide and hydrogen. "Such synthesis gas mixtures are of great importance in the chemical industry," explains Ulf-Peter Apfel.
Stable catalyst
Pentlandite consists of iron, nickel and sulphur and resembles some naturally occurring catalytically active enzyme centres. "A major advantage of this mineral is that it is relatively stable to other chemical compounds found in industrial exhaust streams and acts as a poison for many catalysts," explains Apfel.
Editor: Julia Weiler, Julia.weiler@uv.rub.de
15th November 2018,
2nd Materials Chain International Conference. Read original article
© Materials Chain
For the second time, the Materials Chain International Conference (MCIC) was organized by the correspondent flagship program of the University Alliance Ruhr (UA Ruhr). This year it took place in Bochum from November 12 to 14. About 200 international scientists gathered at the second MCIC to discuss their latest results and to network with high-ranking invited speakers from other renowned institutes such as Oxford, Berkeley or Harvard. Apart from gaining more insight into the broad field of materials science during the 42 lectures, the poster session with more than 80 exhibitors gave young materials scientists adequate space to present their research and to establish new contacts for future collaborations. The wide range of topics allowed even established scientists to think outside the box in a relaxed setting and to learn about latest highlights from other research areas first-hand.
The MCIC 2018 highlighted recent trends in materials science and production technology by giving insight into current top-class research and future prospects in this area. It provided a platform for connecting materials research across borders and boundaries – covering the entire materials chain from basic research on materials to applied technologies and from the fundamental description of materials on the atomic scale to the properties of technical components and their manufacturing.
Key research topics addressed by MCIC 2018 comprised Materials Discovery, Functional Materials and Coatings, Materials for Energy Conversion, Martensitic Transformations, Computational Materials Design, Electronic and Atomistic Simulations, Micromechanical Modelling, Characterizing and Understanding Complex Structures, Microscopy from Atoms to Microstructure, Catalysis and Electrochemistry, and Enhanced Processing.
Like the first Materials Chain International Conference in 2016, MCIC 2018 was jointly organized by Ruhr-Universität Bochum, TU Dortmund University and the University of Duisburg-Essen. The conference aims to offer a platform for cross-location exchange for the 230 research groups involved in the UA Ruhr flagship program Materials Chain in order to strengthen the role of each member and their research topics.
Editors: Pia Aleithe 0234/3229919, pia.aleithe@rub.de; Alexander Heinemann, 0203/3798180, alexander.heinemann@uni-due.de
http://materials-chain.com/news-events/conferences/mcic-2018/
15th November 2018,
Explore Materials Chain. Read original article
© UA Ruhr
The idea of the EXMAC (Explore Materials Chain) concept, which received an award from the DFG in 2017, was successfully transferred into practice in 2018. From October 27 to November 14, 23 UA Ruhr junior scientists performing research in materials science invited 23 international postdocs to the Ruhr Area. Scientists from 12 different countries accepted the invitation to jointly develop and explore ideas for cooperation over a period of two weeks.
For the first time, 46 researchers from Stanford, Oxford, Massachusetts Institute of Technology or National University of Science and Technology – to name just a few – were given the opportunity to work on projects in tandems and to exchange ideas with other program participants to encourage the establishment of their own international networks.
The first meeting took place in the evening on October 28 in Bochum. In a workshop, right at the beginning, the participants were specifically prepared to write joint funding applications. The second week focused on research exchange between hosts and participants. Both sides gained new insights during their discussions. Besides science, the international guests explored the Ruhr Area individually and within their group. They visited the Ruhr Museum in Essen to get an impression on the regional history and the development of the Ruhr area. The EXMAC stay ended on November 9th with a farewell dinner in Essen. Hosts and participants shared their impressions on the program as well as outlooks on their joint projects they had initiated during the two weeks. Most of the guests also took the opportunity to present their own ongoing projects at MCIC 2018 before travelling home.
Editor: Alexander Heinemann, Tel. 0203/ 379-8180, alexander.heinemann@uni-due.de
14th November 2018,
Chemistry.
© RUB, Marquard
Researchers have combined two concepts that make the system as efficient as precious metal catalysts.
Fuel cells that work with the enzyme hydrogenase are in principle just as efficient as those that contain the expensive precious metal platinum as a catalyst. However, the enzymes need an aqueous environment, which makes it difficult for the starting material for the reaction - hydrogen - to reach the enzyme-loaded electrode. Researchers solved this problem by combining previously developed concepts for packaging the enzymes with gas diffusion electrode technology. The system developed in this way achieved significantly higher current densities than previously achieved with hydrogenase fuel cells.
In the journal "Nature Communications", a team from the Centre for Electrochemistry at the RUB, together with colleagues from the Max Planck Institute for Chemical Energy Conversion in Mülheim an der Ruhr and the University of Lisbon, describes how they developed and tested the electrodes. The article was published on November 9, 2018.
Since the enzyme hydrogenase becomes unstable when it comes into contact with oxygen, the Bochum researchers have developed a polymer in recent years in which they can embed the hydrogenases and protect them from oxygen. However, they had previously only tested it on flat electrodes. In the current study, they showed that it also works when applied to a porous three-dimensional structure such as gas diffusion electrodes.
It was also initially unclear whether the electrodes coated in this way would still be gas-permeable - the researchers were also able to answer this question with Yes after their tests.
Editor: Julia Weiler julia.weiler@uv.rub.de
12th November 2018,
Materials Chain Member Jun.-Prof. André Gröschel.
Jun.-Prof. André Gröschel © UDE/Frank Preuß
The Materials Chain member André Gröschel was awarded the renowned Dannie Heineman Prize of the Göttingen Academy of Sciences.
He receives the prize for his work on self-organization processes of colloids and hybrid nanoparticles, in particular on the controlled production of novel structures from well-defined macromolecular building blocks.
The Academy has awarded the prize every two years since 1961. It is not publicly announced. The examination board of the academy proposes the candidates to the plenum.
About the person: Jun.-Prof. André Gröschel: https://www.uni-due.de/chemie/groeschel-lab/
Editor: Ulrike Eichweber, 0203 379-2461, webredaktion@uni-due.de