Nickel Hydroxysulfide Electrocatalyst Promotes Urea Oxidation for Energy‐Saving Hydrogen Production

Abstract The occurrence of oxygen evolution reaction (OER) almost consumes most of the electric energy of hydrogen production by electrocatalytic water splitting. The energy required in the process of electrochemical hydrogen production can be reduced by choosing urea oxidation reaction (UOR) instead of OER. In this work, nickel hydroxysulfide is synthesized on nickel foam (NiSOH/NF) and its electrocatalytic performance was tested in UOR. Experimental results show that the vulcanization catalyst requires a low potential of 1.38 V (vs RHE) to achieve a current density of 100 mA cm −2 in an electrolyte containing 0.5 M urea, which is 270 mV lower than the conventional OER process. This innovative approach has yielded a substantial reduction in the cell voltage necessary for overall water splitting under two electrode system, thereby enhancing its efficiency and feasibility.