Novel plasmonic p-n heterojunction Ag-Ag2CO3/Bi2Sn2O7 photocatalyst for Cr(VI) reduction

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2021-03, Vol.120, p.106-115
• Main Authors: Shen, Jia-chao, Zeng, Hong-yan, Chen, Chao-rong, Xu, Sheng
• Format: Article
• Language: English
• Subjects: Ag-Ag2CO3; Bi2Sn2O7; Cr(VI) reducation; P-N heterojunction photocatalyst; Surface plasmon resonance
• ISSN: 1876-1070; 1876-1089
• DOI: 10.1016/j.jtice.2021.02.025

•The novel plasmonic p-n heterojunction Ag-Ag2CO3/Bi2Sn2O7 photocatalyst were successfully prepared.•The photocatalytic performance of catalysts with different silver loadings was discussed.•Ag-Ag2CO3/Bi2Sn2O7 exhibits excellent photocatalytic activity.•The photocatalytic enhancement mechanism for Cr(VI) reduction was discussed. A novel Ag-Ag2CO3/Bi2Sn2O7 p-n heterojunction photocatalysts with different ratios of Ag/Bi2Sn2O7 were successfully prepared by in-situ precipitation method, which possessed surface plasmon resonance(SPR)-enhanced performances. The structure, morphology, optical and photoelectric properties of the as-synthesized photocatalysts were characterized using various techniques, and their photocatalytic activities was evaluated by reducing Cr (VI) in visible light. Among the Ag-Ag2CO3/Bi2Sn2O7 photocatalysts, the 15% Ag-Ag2CO3/Bi2Sn2O7 prepared at the Ag/Bi2Sn2O7 mass ratio of 15% possess the best photocatalytic activity, which was 7.88 and 3.24 times higher than that of Bi2Sn2O7 and 15% Ag2CO3/Bi2Sn2O7, respectively. And the Cr(VI) removal was still above 87.5% after 5 cycles. It was explained that the formation of Ag2CO3/Bi2Sn2O7 p-n heterojunction and the SPR effect of metal Ago on Ag2CO3 nanoparticles were the reasons for the enhanced photocatalytic activity of Ag-Ag2CO3/Bi2Sn2O7. The present study can provide an new insight into the design of highly efficient Bi2Sn2O7-based photocatalysts for the green and sustainable treatment of Cr(VI)-containing wastewater. [Display omitted]