In-situ constructing amidoxime groups on metal-free g-C3N4 to enhance chemisorption, light absorption, and carrier separation for efficient photo-assisted uranium(VI) extraction

Kaifu Yu; Yi Li; Xin Cao; Ruixiang Wang; Li Zhou; Linzhen Wu; Ningning He; Jia Lei; Dengjiang Fu; Tao Chen; Rong He; Wenkun Zhu

doi:10.1016/j.jhazmat.2023.132356

In-situ constructing amidoxime groups on metal-free g-C₃N₄ to enhance chemisorption, light absorption, and carrier separation for efficient photo-assisted uranium(VI) extraction

J Hazard Mater. 2023 Oct 15:460:132356. doi: 10.1016/j.jhazmat.2023.132356. Epub 2023 Aug 22.

Authors

Kaifu Yu¹, Yi Li², Xin Cao³, Ruixiang Wang³, Li Zhou³, Linzhen Wu³, Ningning He⁴, Jia Lei⁵, Dengjiang Fu³, Tao Chen⁶, Rong He⁷, Wenkun Zhu⁸

Affiliations

¹ State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of National Defence & Nuclear Science and Technology, Southwest University of Science and Technology, Mianyang, Sichuan 621010, PR China; College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, PR China.
² School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001, PR China.
³ State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of National Defence & Nuclear Science and Technology, Southwest University of Science and Technology, Mianyang, Sichuan 621010, PR China.
⁴ College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, PR China.
⁵ State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of National Defence & Nuclear Science and Technology, Southwest University of Science and Technology, Mianyang, Sichuan 621010, PR China; State Key Laboratory of Radiation Medicine and Protection, School for Radiological and interdiscipli-nary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, PR China.
⁶ State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of National Defence & Nuclear Science and Technology, Southwest University of Science and Technology, Mianyang, Sichuan 621010, PR China. Electronic address: chent@swust.edu.cn.
⁷ State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of National Defence & Nuclear Science and Technology, Southwest University of Science and Technology, Mianyang, Sichuan 621010, PR China. Electronic address: her@swust.edu.cn.
⁸ State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of National Defence & Nuclear Science and Technology, Southwest University of Science and Technology, Mianyang, Sichuan 621010, PR China. Electronic address: zhuwenkun@swust.edu.cn.

PMID: 37633015
DOI: 10.1016/j.jhazmat.2023.132356

Abstract

The development of inexpensive and efficient semiconductor catalysts for photo-assisted uranium extraction from seawater remains a huge challenge. Herein, we have successfully synthesized amidoxime-rich g-C₃N₄ (AO-C₃N₄) by simply amidoximing a cyano-rich precursor for photo-assisted uranium extraction from seawater. The amidoxime groups not only served as the U(VI) binding sites for efficient uranium adsorption, but also significantly improved the visible light absorption capacity and carrier separation efficiency via introducing defect energy level, resulting in the excellent photocatalytic activity for AO-C₃N₄ towards photo-assisted uranium extraction. In the process of photo-assisted uranium extraction, U(VI) was first adsorbed by the amidoxime groups on the AO-C₃N₄ and then reduced to U(IV), while (UO₂)O₂·2H₂O and (UO₂)O₂·4H₂O were further formed by the oxidation of U(IV) by superoxide radicals (·O₂^-). Moreover, the generated reactive oxygen species (ROS) under light endowed AO-C₃N₄ with outstanding antibacterial properties, preventing the limitation of uranium extraction capacity from marine biofouling.

Keywords: Amidoxime; Uranium Extraction from Seawater; Uranium Photoreduction; g-C(3)N(4).