Simultaneous Detection and Decontamination of Dichromate Ions: The Fluorescence Response and Photocatalysis of Thiadiazole-Modified Zr-Metal–Organic Frameworks
Xiaojun Hu, Yajing Zhang, Hezhen Liu, Minghui Zhan, Jie Chen, Zhenmin Liu, Hongxia Chen
Abstract
The simultaneous analysis and removal of highly toxic hexavalent chromium (Cr (VI)) in contaminated water via an easy method remain a serious task. Based on the guidance of bibliometric analysis, a thiadiazole ligand-modified zirconium metal–organic framework (Zr-MOF) heralds a new and simple approach to Cr (VI) treatment. The concentration can be determined by fluorescence quenching with a low detection limit of 1.4 μM and a high quenching constant of 6.88 × 10 3 M –1 . For the sensing mechanism, the fluorescence intensity of the Zr-MOF decreased rapidly due to the competition of Cr (VI) with the Zr-MOF for absorption excitation energy and the induction of Zr-MOF aggregation. The analysis system also displayed satisfactory stability and applicability. Apart from sensing application, Zr-MOF can convert Cr (VI) to Cr (III), and the reduction rate constant was 0.004 min –1 under irradiation. Therefore, the bifunctional Zr-MOF provided a potential application method for controlling the pollution caused by Cr (VI) in wastewater.