Self-polarized schorl optimizing TiO2 for photocatalytic persulfate activation and organic pollutants degradation

Yu Tu; Sijia Sun; Hao Ding; Xuan Wang; Zewei Wu

doi:10.1016/j.jhazmat.2023.132120

Self-polarized schorl optimizing TiO₂ for photocatalytic persulfate activation and organic pollutants degradation

J Hazard Mater. 2023 Oct 5:459:132120. doi: 10.1016/j.jhazmat.2023.132120. Epub 2023 Jul 22.

Authors

Yu Tu¹, Sijia Sun², Hao Ding³, Xuan Wang⁴, Zewei Wu¹

Affiliations

¹ Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Xueyuan Road, Haidian District, Beijing 100083, PR China.
² Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Xueyuan Road, Haidian District, Beijing 100083, PR China; MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, school of Water Resources and Environment, China University of Geosciences, Xueyuan Road, Haidian District, Beijing 100083, PR China. Electronic address: ssjcugb@163.com.
³ Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Xueyuan Road, Haidian District, Beijing 100083, PR China. Electronic address: dinghao113@126.com.
⁴ School of Energy Resources, China University of Geosciences, Xueyuan Road, Haidian District, Beijing 100083, PR China.

PMID: 37487333
DOI: 10.1016/j.jhazmat.2023.132120

Abstract

Photocatalytic activation of persulfate has exhibited tremendous potential in water purification because of its green and environmentally friendly process. However, this process often exhibits low activation efficiencies and difficult recovery of the photocatalyst. Herein, schorl-supported nano-TiO₂ composite photocatalysts (S/TiO₂) were prepared by a mechanical grinding method for efficient activation of potassium monopersulfate (PMS). The anatase TiO₂ nanoparticles with particle size of approximately 30 nm was uniformly loaded on the surface of schorl via forming Si-O-Ti bonds. The S/TiO₂ assisted with PMS (S/TiO₂-PMS) exhibited remarkable degradation performance and stability. In this system (S/TiO₂-PMS), the C/C₀ value of phenol solution (10 ppm) were decreased to 0.070 and 0 after 30 min and 90 min of irradiation, where the degradation extent were 93.0% and 100% respectively. The rate of phenol degradation with S/TiO₂-PMS was 12.6 times that seen with TiO₂-PMS. The oxidation active species were holes and SO₄^•- in S/TiO₂-PMS system subjected to simulated sunlight. It was demonstrated that the polarization electric field of the schorl enhanced the separation efficiency of the photoinduced electrons and holes for improving the performance of the S/TiO₂-PMS. On the other hand, the transformations of Fe³⁺ and Fe²⁺ on the schorl surface further promotes the activation of PMS. This work provides a new choice for designing TiO₂-based photocatalytic persulfate activation system targeting the field of advanced oxidation water treatment.

Keywords: Composite photocatalyst; Nano-TiO(2); PMS; Schorl.