Pt-based Intermetallic Nanocatalysts for Promoting the Oxygen Reduction Reaction

Abstract

The oxygen reduction reaction (ORR) is a performance-dictating cathodic reaction in polymer electrolyte membrane fuel cells (PEMFCs), and Pt-based alloy catalysts are the mainstay for the ORR. Owing to their excellent activity and stability, Pt-based intermetallic nanostructures have recently emerged as promising ORR catalysts. Their ordered atomic arrangement of constituent elements with a constant stoichiometry endows higher stability, and more intensified strain and ligand effects than the random alloy phase. In this account, recent advances in Pt-based intermetallic nanocatalysts are reviewed. We illustrate recent advances in synthetic strategies for these catalysts, and discuss the underlying principles for the activity enhancement. We also introduce notable examples that have demonstrated high performances in practical PEMFCs. Finally, current issues and future directions are suggested. We envisage that the rapid progress in the intermetallic nanocatalysts would lead to their widespread usage in PEMFCs in the future.