Novel Zn-Al LDHs based S-scheme heterojunction with coral reef-like structure for photocatalytic activation of peroxymonosulfate towards nitenpyram decomposition. Issue 4 (August 2022)

• Record Type: Journal Article
• Authors: Zheng, Jiangfu; Deng, Yaocheng; Fan, Changzheng; Li, Xiaoming; Gong, Daoxin; Li, Changwu; Ye, Ziyi
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 4(2022)
• Publication Date: 2022-08
• Subjects: Layered double hydroxides -- Bismuth tungstate -- Activated persulfate -- S-scheme heterojunction -- Nitenpyram; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2022.108188
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: The construction of an S-scheme heterojunction is an effective way to enhance the photocatalytic activity of composite materials. Thus, a co-precipitation method is combined with a hydrothermal synthesis method in this study to synthesize an S-scheme heterojunction of Bi2 WO6 /Ag3 PO4 /Zn-Al LDH photocatalyst with an exceptional morphology like a coral reef. On this basis, an AP0.5BWLDH0.3/PMS/Vis reaction system is constructed. The prepared Bi2 WO6 /Ag3 PO4 /Zn-Al LDH composites present better oxidation performance than pure Bi2 WO6, Zn-Al LDH and Ag3 PO4, with 100% Nitenpyram (50 mg/L) degraded within 90 min due to the photocatalytic activation of peroxymonosulfate. The significant increase in photocatalytic activity is not only due to the uniformly distributed coral reef-shaped nanostructures but also the extended life of the carrier with strong redox capability through S-scheme heterojunction. During the simulated exposure to sunlight, the internal electric field, optimized energy band structure, as well as coulomb force interaction all contributed to the promotion of the transportation of electron-hole pairs in the Bi2 WO6 /Ag3 PO4 /Zn-Al LDH composite. For this reason, electrons and holes have high reducing and oxidizing properties, which make the composites have high redox capacity. Then the radical trapping experiments, ESR testing and XPS analysis were used to verify these results. It was revealed that the S-scheme heterojunction mechanism was suitable for the electron migration in a photocatalyst. This study extends the design and preparation ideas of new S-scheme heterojunction photocatalysts and then proposes effective strategies to solve future water pollution. Graphical Abstract: ga1 Highlights: Composite photocatalysts with coral reef-like nanostructures were prepared. The special structure has a larger interfacial area and photocatalytic activity. The NTP was completely degraded within 90 min by illumination. The AP0.5BWLDH0.3/PMS/Vis system exhibits high stability.