Granule-like NiCu nanosheet arrays grown on nickel foam as an efficient and non-precious catalyst for hydrogen evolution reaction

A galvanostatic electrodeposition method was employed to synthesize arrays of NiCu nanosheets effectively on the surfaces of nickel foam. In a 1 M KOH solution, the nanosheet array exhibits remarkable performance, as it only requires a low overpotential of 62 mV to achieve a current density of −10 mA cm−2. Furthermore, the catalyst demonstrates remarkable durability, as indicated by the lack of a significant increase in overpotential after continuous catalysis at a current density of −30 mA cm−2 for a duration of 20 h. The remarkable electrocatalytic activity observed in this study can be attributed to the unique granular structure of the catalyst. This structure provides a larger surface area, thereby exposing more effective active sites for catalysis. Additionally, the granular structure facilitates the penetration of the electrolyte and promotes the diffusion of gas molecules, thereby further enhancing the overall catalytic performance. Compared to other complex catalysts, the NiCu binary catalyst synthesized in this study offers several advantages, including a simple synthesis process, low cost, and exceptional catalytic activity. Therefore, this study presents a promising option for practical applications in the field of electrochemical water decomposition.