Comprehensive Study on the Electrochemical Evolution, Reaction Kinetics, and Mass Transport at the Anion Exchange Ionomer–Pt Interface for Oxygen Reduction Reaction

Understanding the structure evolution, kinetics, and mass transfer for the oxygen reduction reaction (ORR) at the ionomer-catalyst interface is fundamental for the development of anion exchange membrane fuel cells (AEMFCs). Herein, we investigate the structural evolution of ionomer-Pt interfaces during the activation process of polycrystalline Pt (poly-Pt) electrodes and their ORR kinetics and mass transfer characteristics at steady state. The results suggest the ionomer thickness as a critical factor in determining the Pt surface structure and the flux of the O