The electronic structure of the active center of CoSe electrocatalyst was adjusted by Te doping for efficient oxygen evolution.

In order to enhance the energy efficiency of water electrolysis, it is imperative to devise electrocatalysts for oxygen evolution reaction that are both non-precious metal-based and highly efficient. Efficient catalyst design is generally based on electronic structural engineering. Considering the electronegativity disparity between selenium (Se) and tellurium (Te), the tunable bandgaps, and the conductive metallic nature of Te. We designed a material wherein Te atoms are uniformly doped onto the surface of Cobalt tetra selenide (CoSe) nanorods, leading to the synthesis of a defect-rich material. Experimental results demonstrate that Te doping in CoSe increases active sites and optimizes the electronic structure of Co cations, enhancing the design of multi-defect structures. This promotes the generation of the Co(oxy) hydroxide (CoOOH) active phase, enhancing catalytic activity by maximizing the binding strength between Co sites and oxygenated intermediates. Te-CoSe nanorods exhibit good catalytic activity for oxygen evolution reactions, with an overpotential of 269 mV at a driving current density of 50 mA cm and excellent stability in alkaline media (over 100 h). This discovery indicates the feasibility of strategically combining various imperfect structures, thereby unlocking the latent potential of diverse catalysts in electrocatalytic reactions.