A water-stable luminescent Zn(II) coordination polymer based on 5-sulfosalicylic acid and 1,4-bis(1H-imidazol-1-yl)benzene for highly sensitive and selective sensing of Fe3+ ion

Abstract

A fluorescent Zn(II)-based coordination polymer, {[Zn(Hssa)(1,4-bib)(H2O)](H2O)}n (1), has been successfully constructed from 5-sulfosalicylic acid (H3ssa) and 1,4-bis(1H-imidazol-1-yl)benzene (1,4-bib) with zinc acetate by solvothermal conditions, which was further characterized by elemental analysis, IR spectra, and thermogravimetric analysis. Single crystal X-ray structure analysis reveals that 1 crystallizes in a 1D zigzag chain. Of particular interest is that the alternating 1D zigzag chains have been orderly staggered in a 2D parallel arrangement in the crystal structure. These neighboring chains are further connected through π⋯π stacking interactions and OH⋯O hydrogen bonds, resulting in the formation of a 3D supramolecular structure. Furthermore, the photoluminescent properties for metal cations were studied at room temperature. 1 shows intense fluorescence in the solid state and exhibits a highly sensitive and selectivity for Fe3+ through fluorescence quenching effect in aqueous solutions at room temperature.