Enhanced Oxygen Reduction Reaction Activity on Pt-Monolayer-Shell PdIr/Ni-Core Catalysts

Abstract

Platinum monolayer oxygen reduction reaction catalysts offer the most promising possibility of reducing the Pt content without sacrificing its fuel cell performance. Here, we present a facile way of preparing Pt monolayer shell on PdIr-based core catalysts with and without Ni sub-core. They showed much higher activity for oxygen reduction reaction than commercial Pt/C catalyst. Among tested samples, PtMLPd2Ir/Ni/C performs the best having Pt mass activity 14 times and Platinum Group Metal mass activity 0.8 times higher than that of Pt/C. In addition, accelerated durability test indicates its excellent durability, which was demonstrated by a 7.5% decrease in Platinum Group Metal mass activity compared to 64% for the commercial Pt/C catalyst. As a result, the role of Ni sub-core in oxygen reduction reaction activity and durability of PtML on PdIr-based catalysts was also elucidated.