Construction synergetic adsorption and activation surface via confined Cu/Cu2O and Ag nanoparticles on TiO2 for effective conversion of CO2 to CH4

High-performance photocatalysts for catalytic reduction of CO 2 are largely impeded by inefficient charge separation and surface activity. Reasonable design and efficient collaboration of multiple active sites are important for attaining high reactivity and product selectivity . Herein, Cu-Cu 2 O and Ag nanoparticles are confined as dual sites for assisting CO 2 photoreduction to CH 4 on TiO 2 . The introduction of Cu-Cu 2 O leads to an all-solid-state Z-scheme heterostructure on the TiO 2 surface, which achieves efficient electron transfer to Cu 2 O and adsorption and activation of CO 2 . The confined nanometallic Ag further enhances the carrier’s separation efficiency, promoting the conversion of activated CO 2 molecules to •COOH and further conversion to CH 4 . Particularly, this strategy is highlighted on the TiO 2 system for a photocatalytic reduction reaction of CO 2 and H 2 O with a CH 4 generation rate of 62.5 μmol∙g −1 ∙h −1 and an impressive selectivity of 97.49 %. This work provides new insights into developing robust catalysts through the artful design of synergistic catalytic sites for efficient photocatalytic CO 2 conversion.