Plasma electrolysis, single crystal electrodes and structured data for electrocatalysis
Albert Engstfeld , Ulm University, Germany
Electrified metal electrodes are commonly found in the field of electrochemistry and electrocatalysis. The performance of an (electro)catalyst material is determined by its intrinsic activity, selectivity, and stability during operating conditions. These aspects strongly depend on the catalysts’ structural properties, particularly its surface. Therefore, a fundamental understanding of the processes on an atomic scale is essential. Such information is often difficult to obtain from complex three-dimensional materials. Over the past decades, model electrodes, especially with low-index single-crystals, have played a significant role. The potential applied to these electrodes is in the range of millivolts to a few volts, i.e., within or slightly above the stability range of the electrolyte. When electrolysis is performed at significantly higher voltages on gas-evolving electrodes, a plasma can be ignited in a gas sheath, separating the plasma working electrode and the electrolyte. This approach allows for modifying the catalyst’s structure and can induce (electro)chemical degradation of the electrolyte.
First, a brief overview of the fundamental concepts, challenges, and possibilities of high-voltage electrolysis is provided. The role of single-crystal electrodes in this emerging research area will be illustrated. Second, the ongoing need to study single-crystal electrodes in electrocatalysis will be discussed, addressing system-specific questions and comparing new results with those reported over the last decades. Due to partly inconsistent data, deriving correlations can be challenging. A data management approach is presented to mitigate such issues, where experimental, computational, and published data are stored in a structured, machine-readable format, simplifying its exploration, visualization, and evaluation.