<i>In Situ</i> Constructed Cu–Ni Alloy Nanowires Enhance the CO₂ Electrochemical Conversion of Ethylene

Electrocatalysis CO₂ reduction for ethylene(C₂H₄) production based on clean energy is an effective strategy to address energy issues and the climate crisis. However, the limited catalytic selectivity and high production costs of C₂H₄ hinder its commercial application. Here, we employ a nonprecious metal-doping strategy to <i>in situ</i> construct Cu-Ni alloy nanowires (Cu-Ni NWs) on the gas diffusion layer (GDL). Ni-doping modulated the electronic environment of Cu, significantly improving the product distribution of CO₂ reduction. At -1.0 V, the Faradaic efficiency for C₂H₄ reached 49.18%, with a current density of 290.01 mA cm^-2. Furthermore, the Cu-Ni NWs exhibited significant catalytic stability over 40 h. Mechanistic studies indicate that Ni atoms provide more CO₂ adsorption and activation sites on the catalyst surface, facilitating the CO₂RR. Furthermore, Ni doping significantly enhances the adsorption of the *CO intermediate and lowers the kinetic barrier for C-C coupling, directing the reaction preferentially toward the C₂H₄ pathway. This work expands the design space for nonprecious metal catalysts, which should be inspiring for the development of low-cost, high-performance CO₂ reduction electrocatalysts.