Construction synergetic adsorption and activation surface via confined Cu/CuO and Ag nanoparticles on TiO for effective conversion of CO to CH.

High-performance photocatalysts for catalytic reduction of CO 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-CuO and Ag nanoparticles are confined as dual sites for assisting CO photoreduction to CH on TiO. The introduction of Cu-CuO leads to an all-solid-state Z-scheme heterostructure on the TiO surface, which achieves efficient electron transfer to CuO and adsorption and activation of CO. The confined nanometallic Ag further enhances the carrier's separation efficiency, promoting the conversion of activated CO molecules to •COOH and further conversion to CH. Particularly, this strategy is highlighted on the TiO system for a photocatalytic reduction reaction of CO and HO with a CH generation rate of 62.5 μmol∙g∙h 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 conversion.