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

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 VS2@C3N4 with S vacancies via in situ supramolecular self-assembly method. It shows outstanding synergistic hydrogen production rate (9628 mu mol g(-1)h(-1)) and wastewater degradation efficiency as well as stability, which is 16.0 times that of C3N4 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.

Automated summary

In this article, a universal method for the synthesis of compact heterojunction VS2@C3N4 with S vacancies was developed via in situ supramolecular self-assembly method. The material showed outstanding catalytic activity, stability, and hydrogen production rate. The presence of S vacancies resulted in the formation of a compact heterostructure and reduction of the work function, promoting interfacial carriers transfer and surface properties. The core-shell structure also improved the stability of S vacancies. This work not only provides a universal method for the construction of TMD core-shell structure with vacancies, but also deepens our understanding of carrier separation in the vacancies interface for photocatalysis.