LAUSR

The design of efficient and stable photocatalysts for robust CO2 reduction without sacrifice reagent or extra photosensitizer is still challenging. Herein, a single-atom catalyst of isolated single atom cobalt incorporated into Bi3O4Br atomic layers is successfully prepared. The cobalt single atoms in the Bi3O4Br favors the charge transition, carrier separation, CO2 adsorption and activation. It can lower the CO2 activation energy barrier through stabilizing the COOH* intermediates and tune the rate-limiting step from the formation of adsorbed intermediate COOH* to be CO* desorption. Taking advantage of cobalt single atoms and two-dimensional ultrathin Bi3O4Br atomic layers, the optimized catalyst can perform light-driven CO2 reduction with a selective CO formation rate of 107.1 µmol g−1 h−1, roughly 4 and 32 times higher than that of atomic layer Bi3O4Br and bulk Bi3O4Br, respectively.While the conversion of CO2 to high-value products provides a promising means to remove and utilize atmospheric carbon, few materials can do so without wasteful, sacrificial reagents. Here, authors prepare single-atom Co on Bi3O4Br nanosheets as CO2 reduction catalysts using water and light.