Electrodeposited NiCu nanoparticles for the borohydride oxidation reaction: Effect of Cu on the activity and stability of Ni upon surface oxidation

Development cost-effective and stable electrocatalysts for the borohydride oxidation reaction (BOR) is mandatory for the deployment of the direct borohydride fuel cells (DBFC). Ni electrocatalysts have recently been shown to outperform noble-metal (Pt, Pd, Au) catalysts at low BOR overpotentials, but their activity largely depends on the state of the Ni surface with metallic Ni demonstrating the highest activity. Here, bimetallic NiCu nanoparticles of different compositions were prepared, which demonstrate high BOR activity comparable to Ni nanoparticles in the metallic state of their surface and allow to overcome in considerable extent the negative issues related to inevitable surface passivation.