Self-supported NiFeS2/NiFe-LDH nanoflowers for high-efficiency oxygen evolution

Exploiting low-cost and efficient transition metal-based oxygen evolution catalysts is significant for water splitting. Herein, the composite catalyst (NiFeS2/NiFe-LDH) with the flower-like nanostructure was prepared on the surface of nickel–iron binary alloy. The sulfuretted catalyst displays larger Cdl (8.8 mF cm−2) and higher TOF (0.44 s−1). It also showed a low overpotential of 223 mV at 10 mA cm−2. In addition, it shows excellent stability at 10 mA cm−2 and 100 mA cm−2 for 10 h without a noticeable activity loss. The strategy of combining layered double hydroxides with transition bimetallic sulfides may provide important insights for the exploitation of low-cost and high-activity OER catalysts.