Synthesis, structure, and fluorescence sensing properties of zinc coordination polymer based on 4-(2,4-dicarboxylic phenoxyl) phthalic acid ligand

A zinc coordination polymer (Zn - CP) based on H4dpa and bpy ligands (H(4)dpa=4 - (2, 4 - dicarboxylic phenoxyl) phthalic acid, bpy=4,4 '-dipyridine), namely [Zn(H(2)dpa)(bpy)(1.5)](n) (1), has been hydrothermal synthesized and structurally characterized by elemental analyses, IR spectroscopy and single-crystal X-ray diffraction analysis. 1 shows 1D double chain based on Zn2+ ion, H(2)dpa(2-) and bpy ligand. The adjacent 1D double chains further expand into a 3D supramolecular network through hydrogen bonding. Fluorescence studies show that 1 is a fluorescence sensor with high sensitivity, good selectivity, and multiple responses, which can be used for the detection of pesticides and nitro explosives. Interestingly, 2,4,6-trinitrobenzene (TNP), and pyrimethanil (Pth) had an obvious quenching effect on the fluorescence emission of 1, while imazalil (Ima) had an enhancement effect on the fluorescence of 1. In addition, the fluorescence mechanism was investigated by means of UV-Vis absorption spectrum, fluorescence lifetime, and X-ray photoelectron spectroscopy. CCDC: 2215973.