In situ growth of Ag 2 S quantum dots on SnS 2 nanosheets with enhanced charge separation efficiency and CO 2 reduction performance

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2022-03, Vol.10 (13), p.7291-7299
• Main Authors: Rangappa, A. Putta, Kumar, D. Praveen, Wang, Jinming, Do, Khai H., Kim, Eunhyo, Reddy, D. Amaranatha, Ahn, Hyun S., Kim, Tae Kyu
• Format: Article
• Language: English
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/D1TA10463B

Photocatalytic CO 2 reduction to carbon fuels is a desirable solution to replace conventional fossil fuels. Herein, SnS 2 nanosheets (NSs) were fabricated via a facile hydrothermal method, and they transformed to thinner and more homogeneous dispersions with gradually increasing hydrothermal temperature to 200 °C because of the hydrothermal self-exfoliation effect. The obtained SnS 2 -200 NSs displayed optimum photoelectrochemical properties with an excellent light-driven CO production rate. After modification with Ag 2 S quantum dots (QDs) by an in situ cation-exchange reaction, the SnS 2 /Ag 2 S-50 nanocomposites bridged with Sn–S–Ag bonds exhibited 7-fold higher CO/CH 4 (48.7/3.18 μmol g −1 h −1 ) production than pristine SnS 2 -200. The intimate contact between SnS 2 -200 NSs and Ag 2 S through co-shared S atom layers facilitates the photoelectron transfer to the SnS 2 -200 surface and then to Ag 2 S QDs for CO 2 reduction. This study presents a novel example for heterostructure design and offers new opportunities for exploring efficient photocatalytic CO 2 reduction systems for solar-to-chemical energy conversion.