Fe-Doped NiS/NiS on Nickel Foam: A High-Efficiency and Chlorine-Resistant Electrocatalyst for Industrial Seawater Oxygen Evolution Reaction.

Designing effective oxygen evolution reaction (OER) electrocatalysts for seawater electrolysis necessitates the simultaneous optimization of catalytic activity and chlorine corrosion resistance. Herein, Fe-doped NiS/NiS on nickel foam (Fe-NiS/NiS/NF) was prepared through sulfurization of the Fe-doped Ni(OH) precursor. The sulfurization process induces electronic structure modulation, optimizing charge transfer kinetics and generating a high density of catalytically active sites. As a result, Fe-NiS/NiS demonstrates exceptional OER performance, achieving an overpotential of only 320 mV at an industrial current density of 1000 mA cm in alkaline freshwater. Notably, in alkaline seawater, Fe-NiS/NiS maintains outstanding activity (397 mV @ 1000 mA cm) and operational stability (at least 150 h at 100 mA cm). Furthermore, the Fe-NiS/NiS/NF||Pt/C requires a low voltage of 1.73 V to deliver 100 mA cm and exhibits at least 200 h stability, demonstrating its great potential for industrial seawater electrolysis applications.