Suppressive Strong Metal‐Support Interactions on Ruthenium/TiO2 Promote Light‐Driven Photothermal CO2 Reduction with Methane

Strong metal-support interactions (SMSI) have gained great attention in the heterogeneous catalysis field, but its negative role in regulating light-induced electron transfer is rarely explored. Herein, we describe how SMSI significantly restrains the activity of Ru/TiO₂ in light-driven CO₂ reduction by CH₄ due to the photo-induced transfer of electrons from TiO₂ to Ru. In contrast, on suppression of SMSI Ru/TiO₂ -H₂ achieves a 46-fold CO₂ conversion rate compared to Ru/TiO₂ . For Ru/TiO₂ -H₂ , a considerable number of photo-excited hot electrons from Ru nanoparticles (NPs) migrate to oxygen vacancies (OVs) and facilitate CO₂ activation under illumination, simultaneously rendering Ru^δ+ electron deficient and better able to accelerate CH₄ decomposition. Consequently, photothermal catalysis over Ru/TiO₂ -H₂ lowers the activation energy and overcomes the limitations of a purely thermal system. This work offers a novel strategy for designing efficient photothermal catalysts by regulating two-phase interactions.