Preparation of Porous Ni–Cu Alloy Electrodes and their Electrocatalytic Performance as Cathode for Hydrogen Evolution Reaction in Alkaline Solution

Abstract

Porous Ni–Cu alloy electrodes were conveniently fabricated by galvanic displacement reaction (GDR) between Ni foam and copper ion in copper ion solutions, followed by cyclic voltammetry (CV) treatment to form a hierarchical microstructure. The electrocatalytic performance of prepared electrodes in terms of the hydrogen evolution reaction (HER) was investigated in a 1[Formula: see text]mol/L KOH solution at room temperature. Different copper ion solutions were tested to determine the best copper ion solution and the optimum GDR time, and experimental results show that all cathodes obtained by GDR between Ni foam and copper ion exhibit a superior HER activity over the pure Ni foam cathode, while the HER activity of electrode obtained by GDR between Ni foam and copper ion in 0.5[Formula: see text]mol/L CuCl2 solutions for 1[Formula: see text]h is the highest. Furthermore, it is found that the HER activity of electrode obtained by GDR between Ni foam and copper ion in 0.5[Formula: see text]mol/L CuCl2 solutions for 1[Formula: see text]h can be further enhanced through a CV treatment and the optimal number of CV cycles is 3, which can be attributed to a hierarchical microstructure (a needle-like nano–microstructure formed on the surface of the electrode during the CV treatment process).