The synergistic effect of Ag/AgCl@ZIF-8 modified g-C3N4 composite and peroxymonosulfate for the enhanced visible-light photocatalytic degradation of levofloxacin

Jiabin Zhou; Wei Liu; Weiquan Cai

doi:10.1016/j.scitotenv.2019.133962

The synergistic effect of Ag/AgCl@ZIF-8 modified g-C₃N₄ composite and peroxymonosulfate for the enhanced visible-light photocatalytic degradation of levofloxacin

Sci Total Environ. 2019 Dec 15:696:133962. doi: 10.1016/j.scitotenv.2019.133962. Epub 2019 Aug 17.

Authors

Jiabin Zhou¹, Wei Liu², Weiquan Cai³

Affiliations

¹ School of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China. Electronic address: jbzhou@swpu.edu.cn.
² School of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China.
³ School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China.

PMID: 31442719
DOI: 10.1016/j.scitotenv.2019.133962

Abstract

In this work, a series of Ag/AgCl@ZIF-8 modified g-C₃N₄ composites were synthesized and used to degrade levofloxacin (LVFX) in water under visible light irradiation with the assistant of peroxymonosulfate (PMS). The morphologies and physicochemical properties of the materials were characterized by SEM, TEM, XRD, XPS, FTIR, and DRS technologies. The results of photocatalytic experiments showed that in the presence of PMS, the degradation rate of LVFX reached 87.3% in 60min. Furthermore, factors affecting photocatalytic efficiency such as the concentration of PMS, photocatalyst dosage and different pH values were investigated. The degradation products of LVFX were analyzed by LC-MS and the degradation pathway was inferred. Active species trapping experiments indicated that O₂^-, h⁺ and SO₄^- played important roles in the degradation process in the presence of PMS and the possible degradation mechanism was put forward. This work provides a photocatalyst system that is beneficial to the separation of photogenerated carriers and demonstrates the great potential of PMS-assisted photocatalysis in the purification of organic pollutants.

Keywords: Ag/AgCl@ZIF-8; Levofloxacin; Peroxymonosulfate; Photocatalytic degradation; g-C(3)N(4).

MeSH terms

Levofloxacin / chemistry*
Light
Models, Chemical*
Peroxides / chemistry*
Photochemical Processes
Silver / chemistry

Substances

Peroxides
peroxymonosulfate
Silver
Levofloxacin