Correlation between film thickness and oxygen reduction reaction activity at ionomer film coated on Pt single crystal electrode

Abstract

In catalyst layers of polymer electrolyte fuel cell (PEFC), an ionomer such as Nafion is used as a proton conducter and a binder for catalyst particles. Although the interface between a Pt catalyst (Pt) and the ionomer influences the performance of PEFC, the effect of the Pt/ionomer interfacial structure on oxygen reduction reaction (ORR) activity is still unclear. We prepare Nafion films with different thicknesses on a Pt single crystal electrode, and the correlation between the ionomer film thickness and ORR activity was examined.