A self-driven solar coupling system with TiO2@MXene cathode for effectively eliminating uranium and organics from complex wastewater accompanying with electricity generation

Lulin Guo; Yi-Lin Liu; Qingming Zeng; Chao Zhang; Yanjun Wen; Qingyan Zhang; Guolong Tang; Qingsong Zhang; Qingyi Zeng

doi:10.1016/j.jhazmat.2023.133415

A self-driven solar coupling system with TiO₂@MXene cathode for effectively eliminating uranium and organics from complex wastewater accompanying with electricity generation

J Hazard Mater. 2024 Mar 5:465:133415. doi: 10.1016/j.jhazmat.2023.133415. Epub 2023 Dec 30.

Authors

Lulin Guo¹, Yi-Lin Liu², Qingming Zeng¹, Chao Zhang¹, Yanjun Wen¹, Qingyan Zhang¹, Guolong Tang³, Qingsong Zhang¹, Qingyi Zeng⁴

Affiliations

¹ School of Resources & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China.
² School of Resources & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China; School of Mechanical Engineering, University of South China, Hengyang, Hunan 421001, China. Electronic address: liuyilin@usc.edu.cn.
³ School of Resources & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China; School of Mechanical and Electrical Engineering, Qingdao Qiushi College, Qingdao, Shandong 266108, China.
⁴ School of Resources & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China. Electronic address: qingyizeng@usc.edu.cn.

PMID: 38185087
DOI: 10.1016/j.jhazmat.2023.133415

Abstract

The inevitable organic matters in radioactive wastewater and contaminated waters pose great challenge in uranium recycling by traditional techniques. Here, a self-driven solar coupling system (SSCS), which was assembled by a TiO₂ @MXene/CF cathode and a monolithic photoanode, was proposed for synergistically recycling uranium and degrading organics from complex radioactive wastewater, combining with electricity production. The TiO₂ @MXene/CF was prepared via a simple annealing process with in-situ derived TiO₂ nanoparticles decorated Ti₃C₂ MXene coated on carbon felt (CF). Under sunlight illumination, the photoanode captured electrons of organics, and drove electrons to the TiO₂ @MXene/CF, which exhibited an exceptional UO₂²⁺ adsorption and reduction capacity because TiO₂ nanoparticles provided plenty of surface hydroxyl groups for UO₂²⁺ adsorption, and the unique two-dimensional MXene facilitated the charge transfer. The SSCS with TiO₂ @MXene/CF removed almost 100% UO₂²⁺ and organics with rate constants of ∼21 and ∼6.9 times those of the system with CF, accompanying with excellent power output (∼1000 μW·cm^-2). The fixed uranium on TiO₂ @MXene/CF was effectively reduced into insoluble UO₂ (91.1%), and no obvious decay was observed after 15 repeated uses. This study proposes a multi-functional and easy-operated way for remediating radioactive wastewater and contaminated waters, and gives valuable insights in designing cathode materials for uranium reduction.

Keywords: Electricity production; MXene; Organic degradation; Radioactive wastewater; Uranium reduction.