Synthesis, characterization and luminescent sensing property of a novel Zn(II)-organic coordination polymer

A novel luminescent Zn(II)-organic coordination polymer {[Zn(asba)(mbix)(2)(H2O)]center dot H2O center dot DMF}(n) (1) based on the multi-functional 2-amino-5-sulfobenzoic acid (H(2)asba) and the N-donor flexible bis(imidazole) ligand 1,3-bis(imidazole-l-ylmethyl)benzene (mbix) has been synthesized and structurally characterized. 1 shows excellent hydrolytic stability in water. 1 may be used as a potential candidate for wide band gap semiconductor materials through the analysis of the solid state diffuse reflectance UV-vis spectrum. The fluorescence properties of I are greatly dependent on the solvents. 1 exhibits the strongest fluorescence in water. Most interestingly, the fluorescence emission of the aqueous suspension of 1 is selectively quenched by the chromate anions (CrO42-/Cr2O72-) or Fe3+ cation among large pools of the co-existent different anions or metal cations, respectively, revealing that 1 could be used as a potential dual functional fluorescent sensor for trace amounts of the chromate anions or Fe3+ cation. The detection limits obtained through the incremental fluorescence quenching titration experiments reach to sub-ppm level for the Cr (VI) anions (CrO42-/Cr2O72-) and Fe3+ cation, respectively. (C) 2019 Elsevier Ltd. All rights reserved.