Key points are not available for this paper at this time.
Ceria-based bimetallic oxides are promising catalysts for various thermo- and electrocatalytic transformations in renewable energy and chemical sectors. In particular, experimental studies have demonstrated that Cu doping in CeO2 significantly enhances its catalytic performance in the reverse water–gas shift (RWGS) reaction. However, the structure–activity relationship and the reaction mechanism remain under debate. In this work, we construct Cu-doped CeO2 model nanostructures with varying dopant concentrations, guided by published experimental characterization data, and investigate their structural and catalytic behavior by using first-principles calculations. Our results show that increased Cu loading promotes the formation of surface oxygen vacancy clusters, which shifts the Ce oxidation state toward Ce3+, enhancing the reducibility of the catalyst. Density functional theory (DFT) calculations reveal that CO2 prefers to adsorb in the carbonate configuration near Cu-induced vacancy sites, where it is more readily activated to form *COOH intermediates. These pathways are more favorable than the formate route and are consistent with the high CO selectivity observed experimentally. These insights are further supported by finite-temperature, unbiased ab initio molecular dynamics (AIMD) simulations, which show spontaneous oxygen release from Cu-adjacent lattice sites and the formation of *COOH species under operando conditions. This study provides mechanistic insights into the catalytic behavior of Cu-doped CeO2 under operando conditions and offers a predictive framework for understanding surface structure–activity relationships in bimetallic oxide catalysts for CO2 utilization.
Jiang et al. (Wed,) studied this question.