N-doped NiS₂ nanosheets array on carbon fiber as an efficient hydrogen evolution reaction electrocatalyst

Electrocatalytic hydrogen production holds great promise as a means of generating green energy. In order to achieve the large-scale industrial application, low-cost and highly efficient electrocatalysts are the key factors. The open mesh nanosheet array structure and doping can expose more active sites and effectively enhance electron transport during the hydrogen evolution reaction. Herein, a simple nanostructured electrocatalyst consisting of nitrogen-doped NiS₂ nanosheets array grown on carbon fiber cloth (N-NiS₂/CF) has been constructed. Benefiting from its nitrogen-doped, nanosheets array and intrinsic pyrite like structure, the optical N-NiS₂/CF electrode exhibits relatively excellent catalytic activity and long-time stability in both alkaline and acidic media. Especially, to drive the current density of 10 mA cm⁻², only an overpotential of 96 mV and 163 mV were needed in 1.0 M KOH and 0.5 M H₂SO₄, respectively. The as obtained N-NiS₂/CF can be a promising non-noble-metal electrocatalyst for practical hydrogen production application.