Surface/interface regulation of Ni0.85Se via tungsten-doping for enhanced oxygen evolution reaction

Transition metal selenides have attracted wide attention due to their excellent electrocatalytic activity and stability in the oxygen evolution reaction (OER). Doping effectively regulates surface and interface electronic structure, thereby enhancing activity and optimizing kinetic properties. In this study, tungsten (W) was doped into Ni 0.85 Se through a one-step electrodeposition method, producing a self-supported W-Ni 0.85 Se electrode prepared on a stainless steel mesh substrate. The W introduction significantly improved the conductivity, electron transfer ability, and electrochemically active surface area of Ni 0.85 Se, greatly enhancing electrocatalytic performance for OER. In 1 M KOH solution, the electrode exhibited excellent OER activity, with overpotentials of 222 mV and 273 mV at current densities of 50 mA·cm −2 and 100 mA·cm −2 , respectively, and a Tafel slope of 51.2 mV·dec −1 fitted in the current density range of 60 mA·cm −2 to 140 mA·cm −2 . Moreover, after testing for 48 hours at a current density of 100 mA·cm −2 , the catalyst showed almost no significant performance degradation. Density functional theory (DFT) calculations revealed that W doping enhances electron transport, adjusts adsorption/desorption of intermediates, and accelerates OER kinetics. This study provides a new approach for designing efficient, stable, and cost-effective transition metal selenide OER electrocatalysts.