Graphdiyne (CnH2n-2) based CuI-GDY/ZnAl LDH double S-scheme heterojunction proved with in situ XPS for efficient photocatalytic hydrogen production

The photocatalytic performance can be significantly improved by constructing suitable heterojunction photocatalysts. It is well known that graphdiyne possesses a unique conjugated carbon network nanos-tructure, which gives it ample active sites on its surface and facilitates the reduction of protons. In this study, a unique new double S-scheme heterojunction photocatalyst was constructed by simple self-assembly of GDY prepared via organic synthesis methods and ZnAl-LDH. According to the study, an in-ternal electric field controlling the transfer direction of the electron hole is formed between the inter-face of CuI-GDY and ZnAl-LDH, which broadens the light absorption range of the catalyst and improves the redox ability of the photocatalytic system. CuI-GDY and ZnAl-LDH are tightly bound together, which helps to separate the photogenerated carriers while preserving the strong reduction electrons in the GDY conduction band and the strong oxidation holes in the ZnAl-LDH valence band so that they can fully par-ticipate in the redox reaction. The charge-transfer paths on the S-scheme heterojunction interface were analyzed by in situ irradiation XPS. This work provides an effective strategy for the construction of double S-scheme heterojunction photocatalysts.(c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The photocatalytic performance can be significantly improved by constructing suitable heterojunction photocatalysts. In this study, a unique new double S-scheme heterojunction photocatalyst was constructed by self-assembly of GDY and ZnAl-LDH. The formation of an internal electric field between CuI-GDY and ZnAl-LDH interface broadened the light absorption range and improved the redox ability of the photocatalytic system.