Mg-Doped Cu\nCatalyst for Electroreduction of CO<sub>2</sub> to Multicarbon Products:\nLewis Acid Sites Simultaneously\nPromote *CO Adsorption and Water Dissociation

The electroreduction of CO<sub>2</sub> to valuable fuels\nor high-value\nchemicals by using sustainable electric energy provides a promising\nstrategy for solving environmental problems dominated by the greenhouse\neffect. Copper-based materials are the only catalysts that can convert\nCO<sub>2</sub> into multicarbon products, but they are plagued by\nhigh potential, low selectivity, and poor stability. The key factors\nto optimize the conversion of CO<sub>2</sub> into multicarbon products\nare to improve the adsorption capacity of intermediates on the catalyst\nsurface, accelerate the hydrogenation step, and improve the C–C\ncoupling efficiency. Herein, we successfully doped Lewis acid Mg into\nCu-based materials using a simple liquid-phase chemical method. In\nsitu Raman and FT-IR tracking show that the Mg site enhances the surface\ncoverage of the *CO intermediate, simultaneously promoting water dissociation.\nUnder an industrial current density of 0.7 A cm<sup>–2</sup>, the FE<sub>C2+</sub> reaches 73.9 ± 3.48% with remarkable\nstability. Density functional theory studies show that doping the\nLewis acid Mg site increases the coverage of *CO and accelerates the\nsplitting of water, thus promoting the C–C coupling efficiency,\nreducing the reaction energy barrier, and greatly improving the selectivity\nof C<sub>2+</sub> products.