AIE-Photoactive Metal-Organic Framework for the Efficient Elimination of Cr(VI) and Tetracycline in an Aqueous Solution

In this work, based on an AIE-photoactive ligand 2,3,6,7-tetrakis(4-carboxyphenyl)quinoxaline (H(4)TCPQ), a water-stable Cd(II)-Metal-organic framework (MOF), [Cd-4(TCPQ)(2)(H2O)(8)]12H(2)O (CCSFU-1) was successfully synthesized and structurally characterized. This compound features a twofold interpenetration of a (4,4)-connected framework. Due to the entanglement-resulted aggregation of tetraphenylquinoxaline moieties, CCSFU-1 exhibited strong luminescence for the detection of Cr2O72- with a high Ksv value of 4.82 x 10(5) M-1. The hydrophilic channel within the framework facilitated the capture of Cr2O72- (194 mgg(-1)) and tetracycline, hence improving their photoreduction effect. The rate constant k values of photocatalysis for Cr2O72- and tetracycline can reach up to 0.176 and 0.0253 min(-1), respectively, exceeding or in comparison with most of the reported MOF-based photocatalysts. Accordingly, crystal engineering of metal-organic frameworks with AIE photoactivity can provide a feasible platform for the efficient elimination of water pollutants.