A water electrolyzer (WE) is an electrochemical cell that converts electrical energy to chemical energy by means of the endergonic reaction 2H2O + electrical energy -> O2 + 2H2. The conversion of electricity to another form of energy and its consequent storage is a very important topic in the context of the utilization of renewable but intermittent energy sources (e.g., sun and wind).
Anode Exchange Membrane Water Electrolyzers present a crucial step in building the Hydrogen economy, as they combine the advantages of Alkaline electrolyzers (non-noble catalysts) and Proton Exchange Membrane Water Electrolyzers (high efficiencies, variability, compact design). Finding a sufficiently active, stable, and non-noble catalyst for the anode and cathode side of the AEM-WE is one of the leading research goals in the field.
The Ni-Fe/Ni-Co alloys etc. have shown remarkable performance for the anodic oxygen evolution reaction, even in pure water – many catalysts work only in the KOH electrolyte. However, the exact understanding of the Ni, Co, and Fe-based catalysts is still missing.
The objective of this dissertation thesis is to build on the prospective results of the Nanomaterials Group, predominantly in the area of novel catalysts for the oxygen evolution reaction. Magnetron sputtered thin-film catalysts, typically with a structure of Ni,Co,Fe/porous sublayer will be studied with emphasis on the stability and activity dependence on morphology and defect density. Layers of various compositions and morphologies will be prepared with the goal of identifying the ideal structural parameters in terms of both durability and activity. Wide arsenal of analytical methods will be available, ranging from electrochemical testing through X-ray photoelectron spectroscopy to electron microscopy. A great focus will be laid on the operando variants of those methods.