Electronic modulation of sprout-shaped NiCoP nanoarrays by N and Ce doping for efficient overall water splitting

Bifunctional catalysts for hydrogen/oxygen evolution reactions (HER/OER) are urgently needed given the bright future of water splitting hydrogen production technology. Here, the self-supporting N and Ce dual-doped NiCoP nanoarrays (denoted N,Ce-NiCoP/NF) grown on Ni foam are successfully constructed. When the N,Ce-NiCoP/NF simultaneously acts as the HER and OER electrodes, the voltages of 1.54 and 2.14 V are obtained for driving 10 and 500 mA·cm⁻² with a robust durability, and demonstrate its significant potential for practical water electrolysis. According to both experiments and calculations, the electronic structure of NiCoP may be significantly altered by strategically incorporating N and Ce into the lattice, which in turn optimizes the Gibbs free energy of HER/OER intermediates and speeds up the water splitting kinetics. Moreover, the sprout-shaped morphology significantly increases the exposure of active sites and facilitates charge/mass transfer, thereby augmenting catalyst performance. This study offers a potentially effective approach involving the regulation of anion and cation double doping, as well as architectural engineering, for the purpose of designing and optimizing innovative electrocatalysts.