Tuning the electronic structure of NiCoP arrays through V doping for pH-universal hydrogen evolution reaction electrocatalyst

The exploration of cost-effective, high-performance, and stable electrocatalysts for the hydrogen evolution reaction (HER) over wide pH range (0–14) is of paramount importance for future renewable energy conversion technologies. Regulation of electronic structure through doping vanadium atoms is a feasible construction strategy to enhance catalytic activities, electron transfer capability, and stability of the HER electrode. Herein, V-doped NiCoP nanosheets on carbon fiber paper (CFP) (denoted as V_x-NiCoP/CFP) were constructed by doping V modulation on NiCoP nanosheets on CFP and used for pH-universal HER. Benefiting from the abundant catalytic sites and optimized hydrogen binding thermodynamics, the resultant V₁₅-NiCoP/CFP demonstrates a significantly improved HER catalytic activity, requiring overpotentials of 46.5, 52.4, and 85.3 mV to reach a current density of 10 mA·cm^–2 in 1 mol·L^–1 KOH, 0.5 mol·L^–1 H₂SO₄, and 1 mol·L^–1 phosphate buffer solution (PBS) electrolytes, respectively. This proposed cation-doping strategy provides a new inspiration to rationally enhance or design new-type nonprecious metal-based, highly efficient, and pH-universal electrocatalysts for various energy conversion systems.