CuO-decorated dual-phase TiO2 microspheres with enhanced activity for photocatalytic CO2 reduction in liquid–solid regime

Abstract Copper oxide (CuO)-decorated anatase and TiO 2 (B) dual-phase titania microsphere (CuO/TiO 2 (AB)) photocatalysts were synthesized using a facile two-step approach. The photocatalytic reduction of CO 2 to form methyl formate (MF) in methanol was evaluated. The results indicated that the CuO-decorated dual-phase TiO 2 microspheres displayed MF yield of 1800 μmol·g −1 under 4 h illumination, higher than other reference photocatalysts, due to its mixed-phase heterojunction structure and larger surface area, thus leading to an enhanced UV-light response, effective separation and low recombination rate of the photoinduced charge carriers. CuO/TiO 2 (AB) also showed good stability with the MF yield reproducibility greater than 90% in cyclic runs.