Photocatalytic dehydrogenative coupling of silanes with alcohols triggered by light-induced sulfur vacancies on CdS nanosheets

Abstract

Photocatalytic organosilicon transformation is a green and emerging synthetic strategy toward silyl ethers production. This approach takes advantage of the highly reactive photogenerated electron-hole pairs to trigger redox reactions for chemical transformations under mild conditions. However, the development of heterogenous photocatalysts for silyl ethers synthesis is greatly hampered by the lack of sufficient reactive sites on the catalyst surface for the adsorption and activation of silanes. Herein, we demonstrate that the light-induced sulfur vacancies (SVs) in-situ generated on ultrathin CdS nanosheet (CdS-NS) can function as typical Lewis acid sites to adsorb and activate silanes via the formation of SiH···Cd coordination species. In addition, these electron-deficient SVs can also trap the photogenerated electrons to promote charge separation. The CdS-NS with SVs exhibits an excellent photocatalytic performance toward silyl ethers synthesis while producing H2 simultaneously. This synthetic strategy based on in-situ creation of abundant Lewis acid sites on photocatalyst surface to activate silanes will have broad implications in the development of high-performance photocatalysts for organosilicon transformations.