Construction of a bismuth-based perovskite direct Z-scheme heterojunction Au-Cs3Bi2Br9/V2O5 for efficient photocatalytic CO2 reduction
Hui Fu, Xiaolei Liu, Yaqiang Wu, Qianqian Zhang, Zeyan Wang, Zhaoke Zheng, Hefeng Cheng, Yuanyuan Liu, Ying Dai, Baibiao Huang, Peng Wang
Abstract
Photocatalytic reduction of CO 2 to the useful fuels has been supposed to be a hopeful approach to address currently environmental and energy problems. However, photocatalytic CO 2 reduction using H 2 O as a proton source always displays the unsatisfactory activity. Herein, a bismuth-based perovskite Z-scheme heterojunction Cs 3 Bi 2 Br 9 /V 2 O 5 with efficient charge separation and strong redox capability was fabricated for photocatalytic CO 2 reduction. The optimal Cs 3 Bi 2 Br 9 /V 2 O 5 shows a superior photocatalytic CO 2 reduction performance with a CO yield of 37.8 μmol g -1 h - 1 , which is 5.3 times higher than that of Cs 3 Bi 2 Br 9 . With the further help of the Au cocatalyst, the CO yield of the optimal Au-Cs 3 Bi 2 Br 9 /V 2 O 5 increases to 98.95 μmol g -1 h - 1 , superior to most reported perovskite photocatalytic CO 2 reduction performances. The charge transfer process and the mechanism of photocatalytic CO 2 reduction in the Au-Cs 3 Bi 2 Br 9 /V 2 O 5 composite have been thoroughly investigated. This work enriches the perovskite based Z-scheme heterojunctions and expands the application of bismuth-based perovskites in photocatalytic CO 2 reduction.