2D/2D Carbon Nitride/Zn-Doped Bismuth Vanadium Oxide S-Scheme Heterojunction for Enhancing Photocatalytic CO2 Reduction into Methanol

Developing superior photocatalytic CO2 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 (CNZnBVO) nanohybrids were constructed by a facile CTAB-assisted solvothermal strategy to achieve an efficient photocatalytic reduction of CO2 to CH3OH 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 CH3OH generation rate of 609.1 mu mol g-1 h-1 and a high selectivity of 90.5%, outperforming most recently reported CO2 photoreduction systems. Moreover, the yield of CH3OH 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 CO2 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 CH3OH formation. The present work offers a new perspective for the in situ construction of highly active S-scheme heterostructures for selective photocatalytic CO2 reduction.