Mixed ligand coordination polymer based on 4,4′-sulfonyldibenzoic acid and 1,3-bis(2-methyl-1-imidazolyl)benzene: Synthesis, characterization, luminescent and proton conducting properties

A new proton-conductive Zn(II) coordination polymer, namely, [Zn(SDBA)(1,3-BMIB)·H2O]n (1) (1,3-BMIB = 1,3-bis(2-methyl-1-imidazolyl)benzene, H2SDBA = 4,4'-sulfonyldibenzoic acid)) has been synthesized under hydrothermal condition and characterized by elemental analysis, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction study reveals that complex 1 features 2D (4, 4) grid layer. Complex 1 exhibits strong fluorescent emissions in the solid state at room temperature. Moreover, complex 1 also exhibits a proton conductivity of over 10−5 S cm−1 at 328 K and 99% relative humidity.