Two zinc(II) coordination polymers for selective luminescence sensing of iron(III) ions and photocatalytic degradation of methylene blue

Abstract

Two Zn(II) coordination polymers (CPs), [Zn (L1) (DCTP)]n (1) and [Zn (L2) (DCTP)]n (2) [L1 = 1,3-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, H2DCTP = 2,5-dichloroterephthalic acid, L2 = 1,4-bis(benzimidazol-1-ylmethyl)benzene] were hydrothermally synthesized and characterized by elemental analyses, IR spectra, thermogravimetric analyses, fluorescence spectra and single-crystal X-ray diffraction. CP 1 forms a 2D (4,4) layered structure, which is finally extended to a 3D supramolecular framework by the π-π stacking interactions. CP 2 possesses a 3D 3-fold interpenetrating dia network. Both CPs can be as highly selective probes for detection of Fe3+ in aqueous solutions based on luminescence quenching. Further, two compounds exhibit photocatalytic activities for degradation of the methylene blue under UV irradiation.