Inter-regulated d-band centers of the Ni₃B/Ni heterostructure for boosting hydrogen electrooxidation in alkaline media

Ni₃B/Ni heterostructures have been constructed, which exhibit exceptional catalytic performance toward the hydrogen oxidation reaction (HOR) under alkaline media, with the mass activity being about 10 times greater than that of Ni₃B and Ni, respectively, ranking among the most active platinum-group-metal-free electrocatalysts. Experimental results and theoretical calculations confirm electron transfer from Ni₃B to Ni at the Ni₃B/Ni interface, resulting in inter-regulated d-band centers of these two components. This inter-regulation gives rise to optimized binding energies of intermediates, which together contribute to enhanced alkaline HOR activity.