(510c) Using Electric Fields to Understand How Electrolyte Composition Influences Oxygen Reduction Reaction Activity

Understanding the activity of oxygen reduction reaction (ORR) electrocatalysts has traditionally been based on an analysis of the interactions between an electrode surface and adsorbed reaction intermediates. However, recent work has identified that the supporting electrolyte surrounding catalyst active sites can have a significant influence on surface chemistry. The pH of the electrolyte and presence of different electrolyte ions can strongly impact experimental reaction rates and mechanisms, but a comprehensive understanding of this phenomena is lacking. Here, we will discuss results of experimental studies on how pH and alkali metal cations influence the experimental reaction rates and mechanisms for the oxygen reduction reaction. Then, we will discuss how we modeled these changes in electrolyte composition using electric fields in the semiautonomous WhereWulff workflow. These findings may help broaden our understanding of catalysis in complex media and provide insights for optimizing catalysis beyond the active site.