Ultra-low amount Pt-doped Co2P/Ni2P on nickel foam as an efficient electrocatalyst for the hydrogen evolution reaction in an alkaline electrolyte

Abstract

It is still a challenge to design an efficient and low-cost electrocatalyst for the hydrogen evolution reaction (HER) in an alkaline electrolyte. Herein, ultra-low amount Pt-doped Co₂P/Ni₂P on nickel foam (Pt/Co₂P/Ni₂P/NF) was facilely synthesized via an in situ controlled growth and used as an efficient electrocatalyst for electrolytic water splitting into hydrogen. Pt/Co₂P/Ni₂P/NF was achieved by a two-step procedure that was conducted by the hydrothermal approach to obtain the precursor, followed by a subsequent in situ phosphorization procedure. Due to the NF substrate being supermacroporous, more active sites of Pt/Co₂P/Ni₂P/NF could be exposed, improving electron transport and providing open-channels for the rapid release of H₂. Pt/Co₂P/Ni₂P/NF exhibited remarkable electrocatalytic performance towards HER with an overpotential of 75 mV at 10 mA cm⁻² in an alkaline electrolyte and a small Tafel slope of 64 mV dec⁻¹. This work provided a facile and reliable synthetic approach to improve transition metal phosphides (TMPs) for electrocatalytic HER performance in alkaline electrolytes.