High-Throughput Mapping of the Electrochemical Properties of (Ni-Fe-Co-Ce)Ox Oxygen-Evolution Catalysts

Discovering improved electrocatalysts is critical for many technologically important processes and for the development of new clean-energy technologies. High-throughput methods for measuring fundamental electrochemical properties are demonstrated through the investigation of oxygen-evolution catalysis by using 665 oxide compositions containing nickel, iron, cobalt, and cerium. The behavior of each composition is characterized in 1.0 M NaOH(aq) by using a scanning drop three-electrode cell to perform chronopotentiometry (CP) and cyclic voltammetry experiments. CP measurements at different current densities identify different composition-performance trends, owing to underlying variations in fundamental electrochemical behavior. We report systematic, coincident, composition- dependent trends in the Tafel slopes and the reversible redox potentials of the catalysts. Applying high-throughput electrochemical methods provides insight into composition-property- performance relationships and motivates new directions for the study of catalyst mechanisms by using informatics and theory.