Electric field driven tourmaline/hematite dual mineral photocatalysis for efficient antibiotic removal

Xiangwei Tang; Rongdi Tang; Yaocheng Deng; Xiao Li; Ling Li; Zhanpeng Zhou; Wenbo Li; Meng Yuan; Rucheng Xie; Daoxin Gong

doi:10.1016/j.envpol.2024.124135

Electric field driven tourmaline/hematite dual mineral photocatalysis for efficient antibiotic removal

Environ Pollut. 2024 May 9:352:124135. doi: 10.1016/j.envpol.2024.124135. Online ahead of print.

Authors

Xiangwei Tang¹, Rongdi Tang², Yaocheng Deng³, Xiao Li³, Ling Li¹, Zhanpeng Zhou¹, Wenbo Li¹, Meng Yuan³, Rucheng Xie³, Daoxin Gong⁴

Affiliations

¹ College of Environment & Ecology, Hunan Agricultural University, Changsha 410128, China; College of Resources, Hunan Agricultural University, Changsha 410128, China.
² College of Environment & Ecology, Hunan Agricultural University, Changsha 410128, China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
³ College of Environment & Ecology, Hunan Agricultural University, Changsha 410128, China.
⁴ College of Environment & Ecology, Hunan Agricultural University, Changsha 410128, China. Electronic address: gongdaoxin@hunau.edu.cn.

PMID: 38734056
DOI: 10.1016/j.envpol.2024.124135

Abstract

Hematite (Fe₂O₃) has garnered attention due to its stability, economic viability, and non-toxic nature. However, the rapid recombination of charge carriers hampers its practical application. On the other hand, tourmaline's inherent surface electric field facilitates the rapid separation of photogenerated electrons and holes. In this study, two directly mined natural minerals, tourmaline and hematite (TFO), were successfully combined. Characterization and experiments indicate that the pronounced enhancement of photocatalytic activity in Fe₂O₃ is attributed to the electric field effect on the surface of tourmaline. TFO successfully removes 93% of tetracycline (TC, 50 ppm) within 60 min. The reaction rate constant for TFO composite material (0.0410 min^-1) is 8.5 times that of tourmaline (0.0048 min^-1) and 14.1 times that of hematite (0.0029 min^-1). Simultaneously, it markedly improves light absorption and charge carrier separation capabilities. Through simulations of various natural environmental factors, TFO demonstrates excellent practicality. Analyzing and detecting active species revealed the involvement of four types of active species, with ·OH radicals making the most significant contribution. The photocatalytic mechanism was proposed. Furthermore, the degradation pathway of tetracycline and the toxicity of its metabolites were investigated. This work provides additional inspirations and insights for photocatalytic materials performance enhancement and natural resources green governance environment.

Keywords: Electric field; Hematite; Photocatalysis; Tetracycline; Tourmaline.