Complete mineralization of phenolic compounds in visible-light-driven photocatalytic ozonation with single-crystal WO3 nanosheets: Performance and mechanism investigation

Haidong Yu; Mingxi Wang; Jiabao Yan; Hui Dang; Hui Zhu; Yuejin Liu; Meicheng Wen; Guisheng Li; Ling Wu

doi:10.1016/j.jhazmat.2022.128811

Complete mineralization of phenolic compounds in visible-light-driven photocatalytic ozonation with single-crystal WO₃ nanosheets: Performance and mechanism investigation

J Hazard Mater. 2022 Jul 5:433:128811. doi: 10.1016/j.jhazmat.2022.128811. Epub 2022 Mar 31.

Authors

Haidong Yu¹, Mingxi Wang², Jiabao Yan¹, Hui Dang¹, Hui Zhu¹, Yuejin Liu³, Meicheng Wen⁴, Guisheng Li⁵, Ling Wu⁶

Affiliations

¹ Hubei Province Key Laboratory of Coal Conversion and New Carbon Materials, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China.
² Key Laboratory for Biomass-based Environment & Energy Materials in Petroleum & Chemical Industries, School of Chemical and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, China.
³ Hubei Collaborative Innovation Center for Advanced Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, and College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China.
⁴ Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
⁵ School of Materials Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
⁶ Hubei Province Key Laboratory of Coal Conversion and New Carbon Materials, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China. Electronic address: wuling2018@wust.edu.cn.

PMID: 35381509
DOI: 10.1016/j.jhazmat.2022.128811

Abstract

Complete mineralization of phenolic compounds into CO₂ and H₂O is desirable for removing them in wastewater, but it is challenging due to the generated recalcitrant intermediates, which requires highly effective advanced oxidation process with proper catalysts. Herein, we found that single-crystal WO₃ nanosheets (NSs)-based photocatalytic ozonation (PCO) can realize complete mineralization of phenols (phenol and 2-chlorophenol) under visible light irradiation. Almost 100% mineralization ratio of phenols was achieved through WO₃ NSs-based PCO system within short time. By comparing their performances with those of polycrystalline WO₃ nanoparticles, detecting and analyzing the intermediates, identifying the dominant radicals and conducting some electrochemical characterizations, the origin of superior catalytic activity of WO₃ NSs was uncovered, the mineralization pathways and the overall mechanism were proposed. The excellent PCO performance of WO₃ NSs was contributed to their nanosheet morphology with single-crystal microstructure and good dispersion, which can provide continuous interior channels for the photogenerated charge transport from the bulk to surface of WO₃ NSs and enough active sites for the surface reactions triggered by these charges. This work puts forwards new ideas to design highly active photocatalysts for PCO and helps deepen understanding of the catalytic mechanism of PCO.

Keywords: Complete mineralization; Oxalic acid; Phenolic compounds; Photocatalytic ozonation; Single-crystal WO(3).