N-, Se-, and S-Doped Bimetallic NiCoP Nanosheet Arrays as Efficient Hydrogen Evolution Electrocatalysts

N-, Se-, and S-doped NiCoP nanosheet arrays with the same doping content were prepared on nickel foam (NF) as efficient electrocatalysts for the hydrogen evolution reaction (HER). Experimental results and theoretical calculations mutually verified that N, Se, and S doping modulated the electronic structure of NiCoP and thus accelerated the intrinsic charge transport, which eventually enhanced the HER activity. N-NiCoP/NF, Se-NiCoP/NF, and S-NiCoP/NF catalysts show overpotential of 149, 153, and 137 mV at a current density of 100 mA cm^–2, respectively, lower than 154 mV of 20% Pt-C@NF. Additionally, S-NiCoP/NF exhibits long-term robustness for the HER in 120 h of continuous electrolysis with negligible current attenuation. It is expected that S-NiCoP/NF may be applicable in water electrolysis with improved efficiency.