Dispersible CdS1-xSex solid-solution nanocrystal photocatalysts: Photoinduced self-transformation synthesis and enhanced hydrogen-evolution activity

Modulating the electronic structure of Cadmium sulfide (CdS) by non-metallic elements to produce solidsolution photocatalysts serves as a potential route to improve its performance of photocatalytic hydrogen (H-2) evolution. However, exploring an effective synthetic route of CdS-based solid solution is still a great challenge. Herein, the CdS1-xSex solid-solution nanocrystals were successfully synthesized by an accessible photoinduced self-transformation route, including the direct formation of dispersible CdS1-x(SeS)(x) and the in situ self-transformation of selenosulfide ((SeS)(2-)) to Se2- by photoexcited electrons. The prepared CdS1-xSex solid-solution photocatalysts possess a small crystallite size of ca. 5 nm and their band-gaps can be easily tuned in a wide range of 1.84-2.28 eV by tailoring the mole ratio of Se/S. The resultant CdS0.90Se0.10 solid-solution photocatalyst realizes the highest H-2-production tempo of 94.6 mu mol.h(-1), which is 1.6 folds higher than that of CdS. The experimental and theoretical studies supported that the incorporation of Se atoms could not only narrow the bandgap value to reinforce visible-light absorption, but also tune its electronic structure to optimize interfacial H-2-evolution dynamics, thus achieving an efficient photocatalytic H-2-production rate of the dispersible CdS1-xSex solid solution. This study may deliver advanced inspirations for optimizing the electronic structure of photocatalysts towards sustainable H-2 production. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

Modulating the electronic structure of CdS by non-metallic elements can produce CdS1-xSex solid-solution nanocrystals, which exhibit potential for tuning the band gap and optimizing photocatalytic hydrogen production. This study holds significance in optimizing the electronic structure of photocatalysts for sustainable H-2 production.