Nitrogen-Doped Intermetallic PtCo Catalyst with Multilayered Pt-Skin Surfaces for the Oxygen Reduction Reaction

Abstract

Catalysts with a platinum-rich shell and intermetallic core are considered to be one of the most promising catalysts for the oxygen reduction reaction (ORR) in fuel cells. However, too thin of a platinum-rich shell makes the core–shell structure easy to lose. Therefore, the development of the core–shell structure with an appropriate thickness of platinum-rich shell and intermetallic core remains a huge challenge in the field of fuel cells. In this paper, PtCoN-1000/C catalyst with about 1 nm thick platinum-rich shell shows significantly enhanced ORR activity and stability in acidic electrolyte, which is superior to L10-PtCo/C and commercial Pt/C catalysts. The specific power at 0.8 V and mass activity at 0.9 V are 5.60 W mgPt–1 and 0.74 A mgPt–1, respectively. It suggests that the tensile strain and moderately thickened platinum-rich shell led by nitrogen doping can greatly improve the performance of the catalyst.