Sulphur vacancies-VS2@C3N4 drived by in situ supramolecular self-assembly for synergistic photocatalytic degradation of real wastewater and H2 production: Vacancies taming interfacial compact heterojunction and carriers transfer

Abstract

• A facile and universal strategy has been developed to construct S vacancies. • The compact heterostructure to facilitate the separation of carriers. • S vacancies reduced the work function for improving interfacial properties. • VSCN shows excellent synergistic photocatalytic activity. Rational construction of phase interfaces between heterojunction is a significant strategy to enhance catalytic activity but rather limited. In this article, we developed a universal method for the synthesis of compact heterojunction VS 2 @C 3 N 4 with S vacancies via in situ supramolecular self-assembly method. It shows outstanding synergistic hydrogen production rate (9628 μmol g −1 h −1 ) and wastewater degradation efficiency as well as stability, which is 16.0 times that of C 3 N 4 and close to the traditional hydrogen production. Theoretical calculations and experiment results show that S vacancies was resulted in the formation of compact heterostructure and the reduction of the work function, which promoting interfacial carriers transfer and surface properties. Besides, the core shell structure improves the stability of S vacancies. In a word, this work not only provide a universal method to the construction of TMD core–shell structure with vacancies, but also give a deep understanding on the carrier separation in the vacancies interface for the photocatalysis.