One‐step synthesis of anionic S‐substitution toward Ni 2 P (S) nanowires on nickel foam for enhanced hydrogen evolution reaction

Abstract

Hydrogen is considered a promising solution for energy, but the methods that are currently used in hydrogen production continue to rely on fossil fuels. Water electrolysis, a green and sustainable method for hydrogen production, is limited by the lack of nonprecious metal electrocatalysts that exhibit high performance. In this study, novel S-substituted Ni2P nanowires with large aspect ratios were successfully grown on nickel foam (Ni2P(S)/NF) using a facile one-step phosphating-sulfuration heat treatment process. The as-prepared Ni2P(S)/NF exhibited enhanced activity in the hydrogen evolution reaction (HER) performed both in alkaline and acidic media. It only required overpotentials of 171 and 208 mV to drive current densities of 100 mA cm−2 in 1.0 M KOH solution and 0.5 M H2SO4, respectively. The characterization studies and density functional theory calculations suggested that the enhanced catalytic activity can be ascribed to the in situ growth of nanowires on nickel foam, the 1D nanowires morphology with high length-to-diameter ratio, appropriate free energy of hydrogen adsorption, and enhanced H2O binding activity. This work will provide inspiration for the development of non-precious metal HER catalysts.