Selective Reduction of Carbon Dioxide to Ethanol by CuPd–MoO₂: C–C Coupling Enhanced by Bimetallic Active Sites

Photoreduction of carbon dioxide (CO2) into ethanol presents a promising approach toward carbon neutrality. Nevertheless, achieving high selectivity and activity, ethanol production remains fundamentally impeded by inefficient proton coupled electron transfer (PCET) and kinetically constrained C–C coupling. Herein, a 1D MoO2 modified with bimetallic CuPd NPs was constructed for efficient CO2-to-ethanol conversion, which delivers a productivity of 130.4 μmol·g–1·h–1 with 86.9% selectivity. Extensive experimental investigations revealed that the superior photocatalytic activity of CuPd–MoO2 stems from its Cu3Pd configuration. The coexistence of Pd sites and electron-rich Cu sites are highly conducive for strong *COOH adsorption and subsequent C–C coupling. In addition, density functional theory calculations further prove that CuPd NPs could decrease the kinetic barrier of the HOOC–COO* process. This study proposed a strategy for efficient C–C coupling by designing CuPd-based active sites with high electron-accumulation capacity, enabling the efficient conversion of CO2 to value-added C2+ compounds.