Efficient photocatalytic CO 2 reduction achieved by constructing Bi 4 O 5 Br 2 / Bi-MOF Z-scheme heterojunction

Building efficient catalysts is an urgent issue in the field of photocatalytic CO 2 reduction, and Z -scheme heterojunction structures can availably suppress the recombination of photo generated carriers and improve photocatalytic performance. This study successfully prepared a new type of Bi 4 O 5 Br 2 /Bi-MOF composite photocatalyst through self -assembly method. After 5 h of simulated sunlight exposure, the optimized sample 50-Bi 4 O 5 Br 2 /Bi- MOF photocatalytic reduction of CO 2 to CO efficiency (23.78 mu mol center dot g - 1 center dot h - 1 ) was 5.09 times higher than pure Bi 4 O 5 Br 2 , and the CH 4 yield (5.39 mu mol center dot g - 1 center dot h - 1 ) was 2.52 times that of pure Bi-MOF. In addition, in the cyclic experiment, the catalyst had high stability and reusability. The Z -scheme charge transfer mechanism was confirmed through band structure analysis, Electron spin resonance (ESR), Ultraviolet photoelectron spectroscopy (UPS) and other related characterizations. This work provided an important strategy for designing efficient Z -scheme heterojunction photocatalysts.