Dual-ligand Zn-based MOF as a fluorescent probe for the detection of HSO4-

The development of fluorescent probes for the recognition of HSO4- is important for social security and human health. In this work, Zn-MOF ([(Zn2+)(L+)(2)(H2O)(2)]center dot 6(H2O) center dot 2(FDCA(2-))) materials were synthesized using Zn2+ as the metal center and 1,3,5-triimidazolylbenzene (L) and 2,5-furan dicarboxylic acid (FDCA) as the biconjugate. The characterization was carried out by single crystal X-ray diffraction, powder X-ray diffraction (PXRD), thermogravimetric analysis (TG), Zeta potential, and scanning electron microscopy (SEM). The fluorescence sensing experiments showed that Zn-MOF can be used as a fluorescent probe, which produces an obvious fluorescence burst in a short time, and has a good selectivity for the detection of HSO4-, with a low limit of detection (LOD) as low as 0.18 mu M, and a good immunity to interference. The recognition mechanism of ZnMOF was explored by electron transfer analysis methods and density functional theory (DFT) calculations, which indicated that the fluorescence burst mechanism was hydrogen bond formation.