Effect of Experimental Parameters on the Electrocatalytic Performance in Rotating Disc Electrode Measurements: Case Study of Oxygen Evolution on Ni−Co-Oxide in Alkaline Media

Abstract

A preselection of catalysts by screening their performance prior to intensive analysis can save a lot of time and money. A commonly applied screening tool is the rotating disk electrode setup. For powder materials, however, the measured electrocatalytic performance can be influenced by various experimental parameters. Here, a nickel cobalt mixed-oxide is investigated as a model catalyst for the oxygen evolution reaction in alkaline media. The determined electrochemical performance upon variation of the ink composition, catalyst loading, electrolyte concentration, and gas saturation in the electrolyte is systematically evaluated. The results indicate that some parameters do not directly influence the measured performance, whereas others show a significant effect. Special attention is given to the interaction with Fe-impurities present in the electrolyte. The here presented insights into the impact of different parameters can support the interpretation of possible side effects in electrocatalyst analysis.