D-π-A array structure of Bi4Ti3O12-triazine-aldehyde group benzene skeleton for enhanced photocatalytic uranium (VI) reduction

Xin Liu; Rui-Xiang Bi; Feng-Tao Yu; Cheng-Rong Zhang; Qiu-Xia Luo; Ru-Ping Liang; Jian-Ding Qiu

doi:10.1016/j.jhazmat.2023.131189

D-π-A array structure of Bi₄Ti₃O₁₂-triazine-aldehyde group benzene skeleton for enhanced photocatalytic uranium (VI) reduction

J Hazard Mater. 2023 Jun 5:451:131189. doi: 10.1016/j.jhazmat.2023.131189. Epub 2023 Mar 14.

Authors

Xin Liu¹, Rui-Xiang Bi¹, Feng-Tao Yu², Cheng-Rong Zhang¹, Qiu-Xia Luo¹, Ru-Ping Liang³, Jian-Ding Qiu⁴

Affiliations

¹ School of Chemistry and Chemical Engineering, Nanchang University, Nanchang 330031, PR China.
² State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, PR China.
³ School of Chemistry and Chemical Engineering, Nanchang University, Nanchang 330031, PR China. Electronic address: rpliang@ncu.edu.cn.
⁴ School of Chemistry and Chemical Engineering, Nanchang University, Nanchang 330031, PR China; State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, PR China. Electronic address: jdqiu@ncu.edu.cn.

PMID: 36933503
DOI: 10.1016/j.jhazmat.2023.131189

Abstract

Photocatalytic reduction of U^VI to U^IV can help remove U from the environment and thus reduce the harmful impacts of radiation emitted by uranium isotopes. Herein, we first synthesized Bi₄Ti₃O₁₂ (B1) particles, then B1 was crosslinked with 6-chloro-1,3,5-triazine-diamine (DCT) to afford B2. Finally, B3 was formed using B2 and 4-formylbenzaldehyde (BA-CHO) to investigate the utility of the D-π-A array structure for photocatalytic U^VI removal from rare earth tailings wastewater. B1 lacked adsorption sites and displayed a wide band gap. The grafted triazine moiety in B2 introduced active sites and narrowed the band gap. Notably, B3, a Bi₄Ti₃O₁₂ (donor)-triazine unit (π-electron bridge)-aldehyde benzene (acceptor) molecule, effectively formed the D-π-A array structure, which formed multiple polarization fields and further narrowed the band gap. Therefore, U^VI was more likely to capture electrons at the adsorption site of B3 and be reduced to U^IV due to energy level matching effects. U^VI removal capacity of B3 under simulated sunlight was 684.9 mg g^-1, 2.5 times greater than B1 and 1.8 times greater than B2. B3 was still active after multiple reaction cycles, and U^VI removal from tailings wastewater reached 90.8%. Overall, B3 provides an alternative design scheme for enhancing photocatalytic performance.

Keywords: Bismuth titanate; D-π-A array; Photocatalytic reduction; Post-synthesis; Uranium.