Efficient oxygen evolution photocatalyst of BiOBr: In situ light-induced formation of surface oxygen vacancies and application in water splitting

The slow rate of oxygen evolution severely limits the overall water splitting, constructing oxygen vacancies on the surface of photocatalysts is an effective strategy in improving the performance of catalysts. However, the oxygen vacancies can be easily renovated by the adsorbed water and oxygen, then deactivating the catalysts. Herein, we synthesized a nanoflower BiOBr, which could produce continuously sufficient OVs induced by light during the photocatalytic water splitting, and investigated the effect of OVs concentration on the performance of photocatalytic O2 evolution. The results showed that the sustainable light-induced OVs could improve the transfer efficiency of photoinduced carriers and the light absorption capacity, which then cause a significant increase in reaction rates. The optimal oxygen evolution rate could reach 166 μmol·g−1·h−1. This work provides a new way of constructing sustainable oxygen vacancies on the surface of catalysts toward photocatalytic water splitting.