Grass-like Ni/Cu nanosheet arrays grown on copper foam as efficient and non-precious catalyst for hydrogen evolution reaction

Grass-like Ni/Cu nanosheet arrays were successfully grown on copper foam by a simple galvanostatic electro-deposition route. Experiments showed that the as-deposited grass-like Ni/Cu nanosheet arrays possessed excellent electrocatalytic activity for hydrogen evolution reaction (HER). In 1 M KOH solution, the nanosheet arrays only required a low overpotential of 38 mV to deliver a current density of -10 mA cm(-2). Simultaneously, the present catalyst also presented a high durability. After continuously catalyzing for 50 h at a current density of -30 mA cm(-2), the overpotential had no obvious increase. The above outstanding electrocatalytic activity should be attributed to the special grass-like structure of the catalyst, which exposed more effective active sites, promoted electrolyte penetration and facilitated gas diffusion. Compared with other catalysts with complex compositions, the present Ni/Cu binary catalyst is easily synthesized, cost-efficient and highly active for HER, which provides a new selection for electrochemical water splitting in practical applications.