Ni3S2 nanowires supported on Ni foam as efficient bifunctional electrocatalyst for urea-assisted electrolytic hydrogen production

In this work, nickel sulfide (Ni3S2) nanowires were directly grown on nickel foam (Ni3S2@NF) via hydrothermal sulfurization of the nickel foam (NF). The Ni3S2@NF electrode exhibited excellent activity for urea oxidation reaction (UOR), which can deliver a current density of 100 mA cm(-2) at 0.36 V (vs SCE) for UOR in the electrolyte of 1.0M NaOH and 0.33M urea. The Ni3S2@NF electrode also exhibited excellent activity for hydrogen evolution reaction (HER), which shows decent stability and catalytic performance with an overpotential of similar to 127 mv at 10 mA cm(-2) in 1.0M NaOH. The excellent catalytic activity for both UOR and HER renders the Ni3S2@NF an efficient bifunctional electrocatalyst for urea-assisted electrolytic hydrogen production. As a result, the two-electrode system assembled with Ni3S2@NF can drive 20 mA cm(-2) at a cell voltage of only 1.49 V with excellent longevity.