Insight into the degradation of p-nitrophenol by visible-light-induced activation of peroxymonosulfate over Ag/ZnO heterojunction

In this report, the peroxymonosulfate activation over Ag/ZnO heterojunction under visible light (Ag/ZnO/PMS/Vis) for p-nitrophenol (p-NP) contaminant degradation was conducted in detail. Herein, the catalyst dosage was decreased, and the results showed that a dosage of 0.5 g L-1 Ag/ZnO and 4 mM PMS almost completely degraded 30 mg L-1 p-NP after 90 min of irradiation. In addition, the PMS activation mechanism of Ag/ZnO/PMS/Vis system was proposed by investigations of the influence of PMS concentration, the FTIR spectra, UV-Vis spectroscopy, and electrochemical analyses. Additionally, the role of SO4 center dot- in the photocatalytic reaction is determined by a combination of a trapping test using isopropanol and tert-butanol as probe compounds and electron spin resonance (ESR) spectroscopy. This report provides a potential alternative to remove persistent organic contaminants in sewage using PMS incorporated with Ag/ZnO under visible light irradiation. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The study demonstrates the effective degradation of p-NP organic pollutants using Ag/ZnO catalyst and PMS under visible light. Through research on PMS concentration, catalyst structure, and photocatalysis mechanism, the reaction mechanism of the system is revealed. Experimental results indicate that the combination of Ag/ZnO and PMS could serve as a potential method for treating persistent organic pollutants.