Facile synthesis of Ni3S2 nanosheets with abundant active sites induced by Fe incorporation on Ni foam for enhanced oxygen evolution reaction

Abstract

Doping modification of nickel sulfide can effectively improve its electrocatalytic activity. Herein, Ni3S2 nanosheets with abundant active sites induced by Fe incorporation have been supported on Ni foam (NF) by a simple one-pot hydrothermal process. During the hydrothermal process, (NH4)6Mo7O24·4H2O as an auxiliary agent plays a key role in increasing the Fe-doping content. The optimized FeMo-Ni3S2 on the surface of NF presents a tremella-like 3D nanostructure. The FeMo-Ni3S2/NF demonstrates excellent activity and durability toward OER performed in 1 M KOH with a low overpotential of 180 mV at a current density of 10 mA cm−2. According to the turnover frequency results, we found that the catalytic activity of FeMo-Ni3S2/NF and Fe-Ni3S2/NF were proportional to the doping amount of Fe atoms, such results can help us confirm that the active sites of the catalyst is induced by the introduction of atomically dispersed Fe. This work could provide a novel and effective strategy for the design of a highly efficient catalyst.