摘要
The reverse water-gas shift (RWGS) reaction, which converts CO2 and H2 into CO, is a pivotal step in carbon-neutral energy cycles and chemical feedstock production. While Cu-based catalysts exhibit near-ideal CO selectivity, their activity is limited; conversely, non-Cu-based catalysts, particularly Ni and Co, often suffer from excessive hydrogenation to CH4, leading to a fundamental activity-selectivity trade-off. Here, we report a TiO2-supported Fe3O4-xcatalyst uniformly decorated with atomic-scale CuOx clusters via a combined chemical adsorption-reduction and spontaneous oxidation strategy. Notably, introducing only 0.75 wt% Cu increases the CO and CH4 production yield of Fe/TiO2 by 653% and 57-fold, respectively-demonstrating exceptional promotional efficiency with minimal Cu loading. The design integrates (i) interfacial electronic modulation through multiple Ti-O-Fe-Cu heterointerfaces to precisely tune lattice oxygen bond energies and stabilize *COOH intermediates; (ii) defect synergy among TiO2 oxygen vacancies, CuOx defect sites, and Fe oxide defect sites to cooperatively promote CO2 activation, Oads removal, and H2 dissociation; and (iii) reaction-pathway optimization to enhance CO yield, suppress CH4 formation, and lower the apparent activation energy, enabling high CO selectivity and productivity below 300 degrees C. Comprehensive HAADF-STEM, XRD, XAS, and XPS analyses reveal dynamic interfacial electron redistribution and vacancy regeneration under reaction conditions, establishing a direct structure-function relationship. This work provides a mechanistically informed strategy for the rational design of next-generation RWGS catalysts that simultaneously maximize activity, selectivity, and economic viability.