• 文献标题:   Visible light-driven photocatalytic degradation of Microcystin-LR by Bi2WO6/Reduced graphene oxide heterojunctions: Mechanistic insight, DFT calculation and degradation pathways
  • 文献类型:   Article
  • 作  者:   ZHAN MM, HONG Y, FANG Z, QIU DP
  • 作者关键词:   microcystinlr, bi2wo6/rgo, intermediate product, degradation pathway, heterostructure photocatalyst
  • 出版物名称:   CHEMOSPHERE
  • ISSN:   0045-6535 EI 1879-1298
  • 通讯作者地址:  
  • 被引频次:   0
  • DOI:   10.1016/j.chemosphere.2023.138105 EA FEB 2023
  • 出版年:   2023

▎ 摘  要

Developing heterostructure photocatalysts for removing Microcystin-LR (MC-LR) under visible light was of positive significance to control the risk of Microcystins and ensure the safety of water quality. Herein, the Bi2WO6/Reduced graphene oxide (RGO) nanocomposites were prepared via a simple one-spot hydrothermal method for the first time to degrade MC-LR. The optimized Bi2WO6/RGO (Bi2WO6/RGO(3%)) achieved a removal efficiency of 82.3% toward MC-LR, with 1.9-fold higher efficiencies than Bi2WO6, and it showed superior reusability and high stability after 5 cycles. The degradation efficiency of MC-LR demonstrated a negative trend with the initial concentration of MC-LR, fulvic acid, and initial algal density increased, while MC-LR removal rate for the presence of anions was in the order of Cl- > CO3-2 > NO3- > H2PO4-. The degradation efficiency of MC-LR could reach up to 82.3% within 180 min in the neutral condition. The active species detection experiments and EPR measurements demonstrated that the holes (h(+)), hydroxide radicals (center dot OH), and superoxide radicals (center dot O-2(-)) participated in the degradation of MC-LR. The DFT calculations showed that 0.56 of electron transferred from Bi2WO6 to RGO, indicating RGO introduction could prevent the recombination of photoelectrons and holes and was beneficial for MC-LR degradation. Finally, the possible intermediate products and degradation pathways were also proposed by the LC-MS/MS analysis.