Persian buttercup-like BiOBrxCl1-x solid solution for photocatalytic overall CO2 reduction to CO and O2

The photocatalytic overall conversion of CO 2 with H 2 O to chemical fuel and oxygen mimicking natural photosynthesis is a huge challenge in photocatalysis. This work shows the achievement of the solar-driven photocatalytic overall CO 2 reduction with H 2 O to CO and O 2 over a Persian buttercup-like BiOBr x Cl 1-x solid solution. A CO generation rate of 15.86 μmol g −1  h −1 with the approximate stoichiometric O 2 evolution is yielded on BiOBr 0.6 Cl 0.4 solid solution under simulated solar light irradiation, which was about 7.5 and 10.2 times higher than that of pure BiOCl (2.11 μmol g −1  h −1 ) and BiOBr (1.55 μmol g −1  h −1 ), respectively. The enhanced photoactivity is contributed to the mediate band gap and energy level tuned by the formation of BiOBr x Cl 1-x solid solution to facilitate the separation of photogenerated charges. Besides the unique electron structure, the photoinduced oxygen vacancy (O V ) formed on BiOBr x Cl 1-x solid solution also plays an important role in the CO 2 reduction.