One-step synthesis of nickel phosphide nanowire array supported on nickel foam with enhanced electrocatalytic water splitting performance

Abstract

The design and facile synthesis of noble metal-free efficient catalysts to accelerate the sluggish kinetics of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is still a big challenge for electrolytic water splitting. Herein, we present a facile one-step approach for constructing a self-supported nickel phosphide nanowire array/Ni foam electrode (Ni–P NA/NF) by direct phosphorization treatment of commercial Ni foam at low temperature according to a vapor-solid growth mechanism. As a three-dimensional bifunctional water splitting catalyst, the Ni–P NA/NF exhibits outstanding electrocatalytic activity with a low cell voltage of 1.69 V to drive current density of 10 mA cm⁻². In addition, it maintains its high catalytic activity for at least 20 h in alkaline media. The presented synthesis method opens up exciting new avenues to explore the design of self-supported three-dimensional electrodes made of transition metal phosphides, ranging from water splitting to other applications.