Fe-Doped Ni3S2/Ni0.96S 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 Ni₃S₂/Ni_0.96S on nickel foam (Fe-Ni₃S₂/Ni_0.96S/NF) was prepared through sulfurization of the Fe-doped Ni(OH)₂ 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-Ni₃S₂/Ni_0.96S demonstrates exceptional OER performance, achieving an overpotential of only 320 mV at an industrial current density of 1000 mA cm^-2 in alkaline freshwater. Notably, in alkaline seawater, Fe-Ni₃S₂/Ni_0.96S maintains outstanding activity (397 mV @ 1000 mA cm^-2) and operational stability (at least 150 h at 100 mA cm^-2). Furthermore, the Fe-Ni₃S₂/Ni_0.96S/NF||Pt/C requires a low voltage of 1.73 V to deliver 100 mA cm^-2 and exhibits at least 200 h stability, demonstrating its great potential for industrial seawater electrolysis applications.