Detection of antibiotics, nitro explosives and pesticides using two-dimensional Zn (II) coordination polymers constructed with different Nitrogen-containing ligands

• Two new Zn (II) coordination polymers were synthesized and characterized. • 1 and 2 can detect antibiotics, nitro explosives and pesticides. • MOFs can be used to detect the Yanhe River water . Two coordination polymers were synthesized under hydrothermal conditions with Zn (II) as metal ion, 5,5′-(ethane-1,2-diyl)diisophthalic acid (H 4 L) as organic carboxylic acid ligand, 1,2-bimb [1,2-bis (1H-imidazol-1-yl-methyl) benzene] and 1,4-bib [1,4-bis (1-imidazolyl) benzene] as nitrogen-containing ligands, respectively, namely [Zn(L) 0.5 (1,2-bimb)] n ( 1 ), {[Zn(H 2 L)(1,4-bib)]·2H 2 O} n ( 2 ). Coordination polymers materials were characterized by elemental analysis, X-ray single crystal diffraction, thermogravimetric analysis, infrared spectroscopy and X-ray powder diffraction. Both 1 and 2 are 2D network structures. It was found that 1 was responsive to TNP (2,4,6-trinitrophenol), TET (tetracycline) and FLU (fluazinam) by fluorescence quenching method. Their detection limits are 0.13 μmol⋅ L −1 , 0.70 μmol⋅ L −1 and 0.086 μmol⋅ L −1 , respectively. 2 was responsive to DNP (2,4-dinitrophenylhydrazine), TET and FLU. Their detection limits are 0.50 μmol⋅ L −1 , 0.81 μmol⋅ L −1 and 0.18 μmol⋅ L −1 , respectively. The reason for the fluorescence quenching of TNP, TET, and FLU may be resonance energy transfer. The possible mechanism of DNP is energy competition and absorption. The difference in the introduction of nitrogen-containing ligands not only changes the structure of the coordination polymers framework, but also change the fluorescence intensity, thus changing the detection limit. Two new Zn (II) coordination polymers with different structures were synthesized, which can detect antibiotics, nitro explosives and pesticides. Then the mechanism of quenching was discussed.