▎ 摘　　要

A highly active hydrogen evolution reaction (HER) catalyst was synthesized by loading nickel phosphide (Ni2P) nanosheets self-supported on three-dimensional (3D) graphene/nickel foam (G/NF) by using electrodeposition. The G/NF was firstly prepared through the fast electrodeposition of graphene on NF. Ni2P nanosheets were then fabricated by low-temperature phosphidation of the corresponding precursor of Ni(OH)(2) on the G/NF, which was also synthesized through an efficient electrodeposition process. Compared with Ni2P nanosheets on NF without graphene (Ni2P/NF), NF, as well as commercial Pt/C, the Ni2P-G/NF catalyst exhibits high activity in the electrocatalytic HER, revealing a low onset overpotential of 50 mV and a small Tafel slope of 51 mVdec(-1). The catalyst maintained its catalytic activity for at least 60000s in acidic media. The excellent HER performance of Ni2P-G/NF was attributed to the excellent performance of Ni2P, the large 3D framework, and the introduction of graphene.