Role of High-Index Facet Cu(711) Surface in Controlling the C2 Selectivity for CO₂ Reduction Reaction—A DFT Study

The enhancement in CO 2 reduction reaction (CO 2 RR) selectivity determines the success of the catalytic system design of the carbon neutralizing process. Among catalysts, high-index facet copper catalyst offers an opportunity to convert CO 2 into high-value carbohydrates. We investigate the Cu(711) surface through theoretical calculations to explore the high selectivity of the C2 products shown by the experimental observation. Our proposed reaction path showed that the high-index facet Cu(711) surface could promote the dimerization of specific COH intermediate and CO via a radical cross-coupling reaction with an accessible activation energy of C–C coupling reaction of about 0.35–0.70 eV and a thermodynamically favorable transition. By analyzing the electronic structure of the critical intermediates and the CO 2 reduction mechanism, theoretical insights would provide an explicit indication for designing novel Cu materials for multihydrocarbon synthesis.