Surface modification of BiOBr/TiO2 by reduced AgBr for solar-driven PAHs degradation: Mechanism insight and application assessment

Xianbo Sun; Weiyu He; Xiaodi Hao; Haodong Ji; Wen Liu; Zhengqing Cai

doi:10.1016/j.jhazmat.2021.125221

Surface modification of BiOBr/TiO₂ by reduced AgBr for solar-driven PAHs degradation: Mechanism insight and application assessment

J Hazard Mater. 2021 Jun 15:412:125221. doi: 10.1016/j.jhazmat.2021.125221. Epub 2021 Jan 23.

Authors

Xianbo Sun¹, Weiyu He¹, Xiaodi Hao², Haodong Ji³, Wen Liu³, Zhengqing Cai⁴

Affiliations

¹ National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies, East China University of Science and Technology, Shanghai 200237, China.
² Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Center of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, China.
³ The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
⁴ National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies, East China University of Science and Technology, Shanghai 200237, China. Electronic address: caizhengqing@ecust.edu.cn.

PMID: 33516102
DOI: 10.1016/j.jhazmat.2021.125221

Abstract

A novel solar active AgBr/BiOBr/TiO₂ catalyst was synthesized by a facile coprecipitation method for solar-driven water remediation. The synthesized material composed of flower-like TiO₂ nanoparticles loaded on BiOBr nanosheets and with homogeneous surface distributed Ag/AgBr nanoparticles. The internal electric field between BiOBr/TiO₂ heterojunction greatly facilitated the charge carrier migration; the introduction of narrow band gap semiconductors (AgBr and BiOBr) promoted the visible light adsorption; and the Ag/AgBr nanoparticles acted as photosensitizer to further improve the light utilization. The new material showed 7.6- and 4.0-times activity of pure TiO₂ and BiOBr under solar light, and the contribution of reactive species on anthracene degradation followed the order of h⁺ >O₂^•-> •OH. The degradation mechanism and pathway were proposed based on intermediates analysis and DFT calculation. The QSAR analysis revealed that the environmental risks of contaminants were greatly reduced during the photocatalysis process but some intermediates were still toxic. The high photocatalytic activity, stability and adaptability all indicated that this new material owns great application potential for cost-effective photocatalytic remediation of persistent organic contaminants under solar light.

Keywords: BiOBr/TiO(2); PAHs; Photocatalytic; Solar; Toxicity.

Publication types

Research Support, Non-U.S. Gov't