Optimizing Electronic and Geometrical Structure of Vanadium Doped Cobalt Phosphides for Enhanced Electrocatalytic Hydrogen Evolution

Despite the expectation on transition-metal phosphides as precious-metal-free electrocatalysts, the reported performance of these materials still necessitates further improvement. Ingenious regulations of both geometric and electronic structure have been proposed as an effective approach to boost their electrocatalytic properties. In this regard, the self-supported V doped CoP nanowires on nickel foam are prepared to accommodate both optimized electronic structure and desired nanostructure, which enable large surface area, abundant active sites exposure, low charge transfer resistance, as well as favorable H* adsorption. As for the alkaline hydrogen evolution, it only requires a lower potential of 79 mV and 125 mV to drive 10 mA ⋅ cm⁻² and 100 mA ⋅ cm⁻² current with a Tafel slope of 47.41 mV ⋅ dec⁻¹, which prevails over commercial Pt/C catalysts. The catalyst also exhibits excellent durability to retain activity unchanged for more than 16 h. Such a simple and convenient strategy by electronic tuning and structure design provides a new avenue toward the exploration of efficient electrocatalysts.