Realizing improved CO2 photoreduction in Z-scheme Bi4O5Br2/AgBr heterostructure

Architecting Z-scheme heterojunction can restrain the recombination of photoinduced carriers to improve the photocatalytic performance. However, it still lacks high-efficiency catalysts for sustainable photoreduction of CO2. Herein, an Ag-bridged Z-scheme Bi4O5Br2/AgBr heterostructure is successfully developed, which enables room-temperature CO2 reduction driven by solar energy. In this catalyst, the Ag mediator acts as a bridge to shuttle electrons between Bi4O5Br2 and AgBr, separating the electron-hole pairs efficiently and maintaining the original strong reduction reaction. As a result, Z-scheme Bi4O5Br2/AgBr heterostructures show obviously promoted performance of photocatalytic CO2 reduction in contrast with pristine Bi4O5Br2, delivering a high CO2 conversion activity of 6.6 and 1.8 μmol g-1h−1 for CO and CH4 products, respectively. This study reports an effective reference of Z-scheme Bi4O5Br2/AgBr heterojunction for satisfactory photocatalytic solar energy conversion and synthesis of high value-added products from CO2.