Effect of nickel sulfide catalysts with different morphologies on high efficiency alkaline hydrogen evolution reaction

Abstract

An important area of research is the creation of non-precious metal catalysts with increased catalytic activity and stability for the electrolysis of water to produce hydrogen. A viable and effective method for altering the surface structure of electrocatalysts and improving their performance is morphology control. In this study, the amount of ammonium fluoride (NH4F) used in the hydrothermal process was changed to create a range of nickel sulfide (NiS) electrocatalysts with tunable morphologies. The improved NiS catalyst demonstrated exceptional performance in the hydrogen evolution process (HER) because of its expansive active area, elevated surface activity, and gas diffusion channels. In particular, it showed a low Tafel slope of 65.90 mV dec−1 in 1 M KOH electrolyte solution and an overpotential of 97 mV at a current density of 10 mA cm−2. Remarkably, the NiS electrocatalyst maintained its excellent HER performance even after 60-hour durability test. These findings underscore the significance and feasibility of morphology control in achieving desirable catalytic activity.