Constructing partially amorphous NiMoB/NiMoO4−x with borate doping and reduction through one step boosting hydrogen evolution

The pursuit of efficient and stable electrochemical catalysts based on transition metals (TMs) for the hydrogen evolution reaction (HER) is of paramount importance. Herein, a novel partially amorphous NiMoB/NiMoO4-x catalyst with dense nanoparticle assemblies has been prepared with B doping and reduction by one step NaBH4 treatment of smooth nanorod-like NiMoO4 precursor. Benefiting from the MoNi4 alloys partially reduced from NiMoO4 precursor, optimized electronic state through B doping and partially amorphous structure, NiMoB/NiMoO4-x obtained splendid activity for HER with a lower overpotential of 26.2 mV at 10 mA cm2 coupled with a narrow Tafel slope of 66.75 mV dec1, in contrast to NiMoO4 precursor catalyst (260.24@10 mA cm2, 149 mV dec1) in alkaline solution. Additionally, the self-supported NiMoB/NiMoO4-x electrode exhibits remarkable stability, maintaining a current density of 50 mA cm2 for a minimum of 40 hours attributed to mixed phases of MoNi4 and amorphous NiMoO4-x for accelerating the H2 evolution and enhancing water adsorption. This work offers a facile avenue to rationally design high-performance electrocatalysts for enhancing hydrogen evolution with NaBH4 accompanying borate doping and reduction.