Dual quantum dots decorated TiO2 nanorod arrays for efficient CO2 reduction

Abstract To meet the demand of CO2 reduction, we designed a Z-type composite photocatalyst based on vertically aligned rutile TiO2 (r-TiO2) nanorod arrays. The composite photocatalyst was obtained by decorating g-C3N4 and Au quantum dots on the r-TiO2 nanorods. Benefiting from the high charge separation efficiency of C3N4/TiO2 heterojunction and the electron capture effect of Au quantum dots, the composite catalyst indicates a significantly enhanced hydrocarbon yield efficiency. The yield rate of CO can increase to 0.138 μmol cm−2 h−1 and the yield rate of CH4 can reach 0.032 μmol cm−2 h−1 without any sacrificial agents, which is almost 5 times than that of pristine r-TiO2 nanorod arrays. This work provides an efficient strategy to rationally design high-performance photocatalysts by using quantum dots and nanorods (or nanowires) as building blocks.