Vanadium-phosphorus incorporation induced interfacial modification on cobalt catalyst and its super electrocatalysis for water splitting in alkaline media

Co-based compounds have been considered as promising earth-abundant electrocatalysts for water splitting, however, the catalytic performance need to be further enhanced. Herein, we report a nickel foam (NF) supported Co-VOx-P nanoflower electrocatalyst that shows excellent catalytic performances, achieving a small overpotential of 230 mV at 100 mA/cm 2 for OER. Such performances surpass the recently reported best-performing Co-based catalysts in alkaline media. In addition, the present Co-VOx-P electrocatalyst can deliver 10 mA/cm 2 with a small overpotential of 98 mV for HER. Experimental and DFT studies indicate that, due to the combination of P and V, the Co-VOx-P electrocatalyst shows improved intrinsic catalytic properties including enhanced conductivity, facile electron transfer and favorable surface adsorption strength. The strategy demonstrated here by incorporating metalloid with high valence states may be extended to design other cost-efficient electrocatalysts for more advanced water splitting performances.