Efficient Photoreduction of CO 2 to CO with 100% Selectivity by Slowing Down Electron Transport.

It remains challenging to obtain a single product in the gas-solid photocatalytic reduction of CO 2 because CO and CH 4 are usually produced simultaneously. This study presents the design of the I-type nested heterojunction TiO 2 /BiVO 4 with controllable electron transport by modulating the TiO 2 component. This study demonstrates that slowing electron transport could enable TiO 2 /BiVO 4 -4 to generate CO with 100% selectivity. In addition, modifying TiO 2 /BiVO 4 -4 by loading a Cu single atom further increased the CO product yield by 3.83 times (17.33 μmol·g cat -1 ·h -1 ), while maintaining 100% selectivity for CO. Characterization and density functional theory (DFT) calculations revealed that the selectivity was mainly determined by the electron transport of the support, whereas CO 2 was efficiently adsorbed and activated by the Cu single atom. Such a two-step regulation strategy of combining heterojunction with single atom enhances the possibility of simultaneously obtaining high selectivity and high yield in the photocatalytic reduction of CO 2 .