Photothermal CO₂ Reduction to CO with Ultrahigh Selectivity Enhanced by Au–O–Ce Bond in Au–CeO₂

CeO₂ is a promising photothermal catalytic candidate in the field of CO₂ resource conversion. However, its further application is limited by insufficient visible light absorption and photogenerated carrier recombination. This study prepared a Au–CeO₂ photothermal catalyst with high performance via low-temperature in situ reduction. Through the synergistic effect of the Au–O–Ce interface and photothermal action, the prepared Au–CeO₂ achieved a CO production rate of 2,971.3 μmol/g within 3 h (147 times higher than pure CeO₂), with 99.9% CO selectivity and no obvious activity degradation over 12-h continuous operation. The in situ characterization and density functional theory calculations showed that localized surface plasmon resonance effect of Au nanoparticles efficiently captures visible light into local thermal energy and high-energy hot electrons. Heat energy not only provides additional kinetic energy for the reaction, reducing the activation energy barrier of the reaction’s rate-limiting step, but also drives the desorption of the product CO. The Au–O–Ce interface acts as an electron transfer bridge, promoting hot electron injection into the conduction band of CeO₂ to substantially reduce the ^*CO₂→^*COOH activation barrier and inhibit carrier recombination. This work provides expandable interface engineering insights for designing efficient, stable, low-cost photothermal catalysts with high CO selectivity.