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

The development of non-precious 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 co-sputtering method, and their corresponding electrocatalytic performance towards HOR in alkaline media are systemically studied. Both the intrinsic activity and anti-oxidation 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.