LAUSR

Metal sulfides are considered excellent materials for oxygen evolution reaction because of their excellent conductivity and high electrocatalytic activity. In this report, the NiS-Cu2S composites were prepared on copper foam (NiS-Cu2S-CF) using a facile synthetic strategy. The scanning electron microscopy results confirmed that the NiS nanoneedles were successfully grown on Cu2S nanoflakes, greatly increasing the active sites. Particularly, the optimized 15% NiS-Cu2S-CF composite demonstrated excellent oxygen evolution activity with a small overpotential of 308 mV@20 mA cm−2, which is significantly smaller than that of noble metal-based electrocatalysts and other NiS-Cu2S-CF composites. The enhanced oxygen evolution activity is attributed to the unique morphology that can provide ample active sites, rich ion-transfer pathways, and the synergistic effect between NiS and Cu2S, which can boost the electron transfer rate.