Exploring the Composition–Activity Relation of Ni–Cu Binary Alloy Electrocatalysts for Hydrogen Oxidation Reaction in Alkaline Media

The development of nonprecious electrocatalysts for hydrogen oxidation reaction (HOR) in alkaline is becoming one of the major obstacles to alkaline polymer electrolyte fuel cells (APEFCs). In this work, a series of Ni–Cu binary alloy films are high-throughput prepared using a combinatorial magnetron cosputtering method, and their corresponding electrocatalytic performances toward HOR in alkaline media are systematically studied. Both the intrinsic activity and antioxidation property of Ni are remarkably enhanced after Cu doping. A volcano-type relation between HOR activity and Cu doping content is revealed. The maximum activity is found at ca. 40 at. % Cu, with the exchange current density 4 times higher than that of pure Ni. This study gives us a deeper understanding of the impact of Cu addition on the HOR catalytic activity of Ni.