Facile synthesis and electrochemical performances of three dimensional Ni3S2 as bifunctional electrode for overall water splitting

Highlight• Three dimensional Ni₃S₂ /Ni foam as electrodes for overall water splitting have been achieved by the facile solvothermal route in various organic solutions. • Three dimensional Ni₃S₂ /Ni foam electrode displayed excellent HER and OER properties. • Low potential (1.89 V@ 20 mA cm⁻²) for overall water splitting was achieved. 3D Ni₃S₂ /Ni foam electrocatalysts were successfully synthesized through a facile one-step solvothermal method in Methanol, Ethanol and Ethylene glycol solutions, then directly applied as the electrodes for hydrogen evolution reaction and the oxygen evolution reaction. The electrochemical measurements demonstrated the excellent electrochemical activity and stability toward water splitting, Moreover, the electrocatalytic behaviors of the samples were also investigated at various temperatures (0–60 °C), systematically. Remarkably, the electrolyzer based on 3D Ni₃S₂ /Ni foam electrodes delivered a current density of 20 mA cm⁻² at a cell of voltage of 1.89 V and shows excellent long-term stability. The porous three dimensional structure of Ni₃S₂/NF electrodes, electrical conductivity, and large electrochemical surface area are responsible for the excellent electrocatalytic performances The study presents a feasible and effective strategy to prepare highly efficient electrocatalysts for water splitting.