An electrocatalyst with anti-oxidized capability for overall water splitting

An anti-oxidized NiS₂ electrocatalyst with improved catalytic activity was developed using a Fe-induced conversion strategy. X-ray photoelectron spectroscopy reveals that betatopic Ni species with high valence states are present within the Fe-NiS₂ matrix and relatively less oxidized layers exist on the catalyst's surface, indicating its greatly enhanced anti-oxidized capability. Density functional theory calculations reveal that the Ni and Fe sites on the Fe-NiS₂ catalyst surface possess strong adsorption capacity toward hydroxyl ions compared with the Ni sites on NiS₂. Benefiting from its unique microstructure and modulated electronic structure due to the effects of iron species, the Fe-NiS₂ catalyst prepared on carbon fiber delivers a remarkably enhanced catalytic activity and superior long-life durability for overall water splitting. The present results provide an efficient strategy for the design and configuration of anti-oxidation catalysts, especially for energy storage and catalysis.