One-pot synthesis of nickel sulfide with sulfur powder as sulfur source in solution and their electrochemical properties for hydrogen evolution reaction

Among low-cost and earth-abundant elements, the nickel-based HER catalysts, particularly nickel sulfide, are considered as one of the most promising candidates in this field. In this paper, a kind of spherical nickel sulfide material was obtained using nickel acetate and sulfur powder as precursors by one-pot synthesis. The use of sulfur powder as sulfur source with solution-based method will enable the synthesis of metal sulfides to be more simple and capable of mass production. In addition, the as-synthesized nickel sulfide exhibits an onset overpotential of as low as 25 mV, a Tafel slope of 90 mV dec− 1, and an exchange current density of 0.44 mA cm− 2. Furthermore, this catalyst maintains its catalytic activity for at least 25 h and only requires overpotentials of 42 and 113 mV to attain current densities of 2 and 10 mA cm− 2, respectively. The electrocatalytic performance is promising for applications as non-noble-metal HER catalyst with water splitting for hydrogen production.