Zn-based coordination polymers with tricarboxylic acid ligand: fluorescence sensor toward Fe3 and MnO4−

Two new coordination polymers, {[Zn2(HBTC)2(bpy)2(H2O)3]•2H2O}n 1 and {[Zn(BTC)(Hdpa)]•H2O}n 2 ((H3BTC = 1,2,4-benzenetricarboxylic acid, bpy = 4,4′-bipyridine, Hdpa = 4,4′-dipyridylamine), have been synthesized under pH-controlled hydrothermal conditions. Their structures were characterized by IR spectrum, single-crystal X-ray diffraction, powder X-ray diffraction (XRD), thermal gravimetric analysis (TGA), UV–vis spectroscopy, EDS and ICP-MS. Complexes 1 and 2 exhibit binuclear units. 1 shows 1D chain structure, while in 2 the network is assembled from binuclear units. It was extended into 3D supramolecular framework by π-π stacking interactions and hydrogen bonded interactions. Complex 2 displays excellent luminescence in the solid state and solution. Importantly, it can act as multi-responsive luminescent sensors for Fe3+ and MnO4− with high selectivity and sensitivity.