Free-Standing P-Doped NiSe₂/MoSe₂ Catalyst for Efficient Hydrogen Evolution in Acidic and Alkaline Media

Abstract

Developing earth-abundant electrocatalysts with high activity and good durability for hydrogen evolution reaction (HER) in both acidic and alkaline media toward alkaline conditions is crucial for achieving a sustainable hydrogen energy economy. Herein, we develop P-doped bimetallic NiSe2–MoSe2 with optimum Ni/Mo proportions (1-1) grown on carbon cloth (P-NiSe2/MoSe2(1-1)@CC) by a facile, low-cost hydrothermal ion exchange reaction (P replaces partial Se ion). Remarkably, the free-standing P-NiSe2/MoSe2(1-1)@CC catalyst exhibits good HER activity with the overpotential of 93/175 mV at 10 mA cm–2 and a small Tafel slope of 52/78 mV dec–1 in acidic/alkaline solution. Density functional theory (DFT) calculations prove the P-NiSe2/MoSe2(1-1)-Ni has a small |ΔGH*| value of 0.17 eV, and the density of electronic states is enhanced around the Fermi level. The experimental and theoretical results reveal P doping has a positive contribution for the better HER activity of P-NiSe2/MoSe2(1-1)@CC.