LED illumination-assisted Activation of Peroxydisulfate by Heterogeneous Cu2S under Alkaline Condition for Efficient Organic Pollutants Removal

Cai-Wu Luo; Liang Jiang; Chao Xie; Deng-Gao Huang; Tian-Jiao Jiang

doi:10.1016/j.envres.2024.120634

LED illumination-assisted Activation of Peroxydisulfate by Heterogeneous Cu₂S under Alkaline Condition for Efficient Organic Pollutants Removal

Environ Res. 2024 Dec 19:120634. doi: 10.1016/j.envres.2024.120634. Online ahead of print.

Authors

Cai-Wu Luo¹, Liang Jiang², Chao Xie², Deng-Gao Huang³, Tian-Jiao Jiang⁴

Affiliations

¹ School of Resources Environment and Safety Engineering, University of South China, 421000, China. Electronic address: luocaiwu00@126.com.
² School of Resources Environment and Safety Engineering, University of South China, 421000, China.
³ Department of Nuclear Technology and Application, China Institute of Atomic Energy, Beijing, 102413, China.
⁴ School of Nuclear Science and Technology, University of South China, 421000, China.

PMID: 39709118
DOI: 10.1016/j.envres.2024.120634

Abstract

The copper-based materials were considered as promising catalysts for the activation of peroxydisulfate (PDS), but the study on the Cu₂S-activated PDS under LED illumination and alkaline condition was little reported. In this work, Cu₂S, a simple and readily available heterogeneous catalyst, was employed to enhance the activation of PDS under alkaline condition through LED illumination. The results indicated that under LED illumination, the degradation rate of tetracycline (TC) during the first 15 min was 3.55 times higher than that of the darkness. A series of important influencing factors were optimized, including anions, humic acid and complex water matrices. The results showed that the Cu₂S/PDS/LED system exhibited excellent adaptability. Besides, the Cu₂S maintained a good stability. The quenching experiments and electron spin resonance analysis demonstrated that the electron transfer and ¹O₂ were two primary pathways for the degradation of TC, and also other species such as SO₄^•- and •OH played important roles. Furthermore, X-ray photoelectron spectroscopy characterization and a series of experiments confirmed that the Cu⁺ was the primary catalytic active site, while the S^2- could directly activate PDS and accelerate the cycles of Cu²⁺/Cu⁺. The toxicity test proved that the toxicity of TC decreased after the degradation. This study not only highlighted the potential of the Cu₂S/PDS/LED system for efficient TC degradation under alkaline condition but also provided new insights for the development of Cu-based catalytic technologies.

Keywords: Alkaline; Cu(2)S; Non-radical; Organic pollutants; Peroxydisulfate.