Visible-to-UVC driven upconversion photocatalyst sterilization efficiency and mechanisms of β-NaYF4: Pr3+, Li+@BiOCl with a core-shell structure

Ying Zhang; Yujie Luo; Shiqi Fu; Xiulong Lv; Qian He; Fangying Ji; Xuan Xu

doi:10.1016/j.jenvman.2021.112394

Visible-to-UVC driven upconversion photocatalyst sterilization efficiency and mechanisms of β-NaYF₄: Pr³⁺, Li⁺@BiOCl with a core-shell structure

J Environ Manage. 2021 Jun 15:288:112394. doi: 10.1016/j.jenvman.2021.112394. Epub 2021 Mar 26.

Authors

Ying Zhang¹, Yujie Luo², Shiqi Fu², Xiulong Lv², Qian He², Fangying Ji³, Xuan Xu⁴

Affiliations

¹ Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China. Electronic address: 201817131178@cqu.edu.cn.
² Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China.
³ Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China. Electronic address: jfy@cqu.edu.cn.
⁴ Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China. Electronic address: xuxuan@cqu.edu.cn.

PMID: 33774566
DOI: 10.1016/j.jenvman.2021.112394

Abstract

UVC (wavelength < 280 nm) has a wide range of applications in the field of water disinfection due to its excellent bactericidal performance. In this work, we synthesized an upconversion luminescent material, β-NaYF₄: Pr³⁺, Li⁺ (NYF), which can generate UVC, and compounded it with a BiOCl photocatalyst to synthesize β-NaYF₄: Pr³⁺, Li⁺@BiOCl (NYF-Bi) with a core-shell structure. The NYF-Bi composite material can be driven under visible light and has high photocatalytic activity. The bactericidal performance of NYF and NYF-Bi were evaluated using Escherichia coli, Staphylococcus aureus, Shigella and Salmonella. The NYF-Bi composite material killed 99.99% of E. coli under visible light (λ ≥ 420 nm) within 180 min and maintained high germicidal efficacy after 4 cycles. Finally, we deduced the sterilization mechanism of the NYF-Bi composite material through carrier dynamics studies and catching agent experiments. The death of bacteria was mainly caused by UVC light and active species, including h⁺, OH, and O- 2. This research provides a new material for water disinfection.

Keywords: Carrier dynamics; Photocatalysis; Sterilization; UVC; Upconversion.

MeSH terms

Catalysis
Disinfection*
Escherichia coli*
Light
Staphylococcus aureus