Additively Manufactured Iron-Based Bulk Metallic Glass Composite Electrocatalysts: Effect of crystallinity/amorphous ratio on the Oxygen Evolution Reaction Activity
Ricardo Alonso Martinez Hincapie, Max-Planck-Institut für Chemische Energiekonversion, Mülheim an der Ruhr, GermanyViktor Čolić, Max-Planck-Institut für Chemische Energiekonversion, Mülheim an der Ruhr, Jan Wegner, University of Duisburg-Essen, Duisburg, Stefan Kleszczynski, University of Duisburg-Essen, Duisburg,
The influence of crystallinity and short- and long-range order in complex alloys on the electrocatalytic activity of these materials requires further clarification in order to optimize their properties. In this work, the electrocatalytic properties of additively manufactured Fe-based bulk metallic glasses (BMG) and their activity toward the oxygen evolution reaction (OER) was studied in alkaline media. The electrodes were prepared by laser powder bed fusion (PBF-LB/M) with different number of Fe75Mo14.3Ni1.6P6C2.2B1 layers applied on a 316L stainless steel substrate. Electrochemical and physicochemical characterization techniques were used to characterize the surface of the electrodes as built and after devitrification. Although the BMG-modified electrodes display similar electrochemical responses, certain differences can be observed with different numbers of layers of deposited metallic glass. Namely, the number of layers and the ratio of crystalline/amorphous phases for all the electrodes seems to determine the catalytic activity observed. In particular, it is observed that more crystalline samples display higher activities, contrary to some previous observations on different materials. The measurements indicate there is a complex interplay between crystallinity and active surface area that determines the electrochemical properties of the investigated electrode material.