2D/2D Carbon Nitride/Zn-Doped Bismuth Vanadium Oxide S-Scheme Heterojunction for Enhancing Photocatalytic CO<sub>2</sub> Reduction into Methanol
Keke Li, Yating Zhang, Jia Jia, Lisi Zheng, Boni Li, Xue Li, Ting Zhang, Xiangyu Feng, Guoyang Liu
Abstract
Developing superior photocatalytic CO 2 conversion systems for the generation of high-valued fuels or chemicals is highly desirable but is still challenging work. Herein, the well-organized carbon nitride/Zn-doped bismuth vanadium oxide (CN-ZnBVO) nanohybrids were constructed by a facile CTAB-assisted solvothermal strategy to achieve an efficient photocatalytic reduction of CO 2 to CH 3 OH under UV–vis light. Impressively, the distinctive butterfly-like 2D/2D CN-ZnBVO catalyst showed markedly enhanced photocatalytic performance in alkaline medium, with the largest CH 3 OH generation rate of 609.1 μmol g –1 h –1 and a high selectivity of 90.5%, outperforming most recently reported CO 2 photoreduction systems. Moreover, the yield of CH 3 OH remained nearly constant over three successive repeated cycles, signifying its good stability. Detailed characterization and theoretical calculations revealed that the outstanding photocatalytic activity owes much to the more accessible reaction sites and improved CO 2 absorption capacity induced by the distinctive micromorphology effect, as well as the localized charge density distribution and fast spatial charge separation and transfer caused by the 2D/2D S-scheme heterojunction, thus providing more photogenerated electrons for efficient CH 3 OH formation. The present work offers a new perspective for the in situ construction of highly active S-scheme heterostructures for selective photocatalytic CO 2 reduction.