Multimetal-substituted pyrite-type NiS2 nanosheets for bifunctional electrocatalysis in alkaline media

Efficient bifunctional electrocatalysts are vital for water electrolysis. We overcome limitations of sulfide catalysts by fabricating FeAlVNi dual-sulfide nanosheets via a quaternary synergy strategy. Fe/V dual-doping, validated by PDOS, enhances the density of states near the Fermi level. The nanowire structure ensures efficient charge transport (70% lower impedance) and abundant active sites. In 1 M KOH, the catalyst shows low overpotentials of 214 mV (OER) and 88 mV (HER) at 10 mA cm -2 , requiring only 1.65 V for overall water splitting. Fe/V optimize electronic structure while Al enhances stability, offering new insights for designing multicomponent sulfide catalysts.