(Invited) Engineering the Microstructure and Atomic Arrangement of Pt-Based ORR Catalyst for High Activity and Durability
Pt-based ORR catalysts still dominate in PEMFC. The main requirements for an effective ORR catalyst are low Pt loading, high activity and durability. We used a PVD based method to engineer the microstructure and atomic arrangement of Pt into a 2-D connected network on worm-shaped islands of conductive metal oxides, which are deposited on graphitic carbon. A model catalyst was first developed on flat surface graphene, and it showed much improved activity and durability. Later, this desired Pt 2-D structure and morphology was replicated onto graphitic carbon powders. In this talk, we will discuss the catalyst, its development, and structural and electrochemical characterization using RDE and in-situ single cell experiments. A mechanistic understanding for the improvement in both activity and durability will be discussed.