Preparation and characterization of two novel three-dimensional supramolecular networks with blue photoluminescence

Two novel photoluminescent coordination polymers of formula [Cd(atpt)(H2O)2] · 2H2O (1) and [Zn(atpt)(H2O)2] (2) (H2atpt = 2-aminoterephthalic acid), in which the amino group of the atpt ligand coordinates to the metal(II) ions for the first time, have been synthesized through the self-assemblies of H2atpt and N-containing ligands [nicotiamide for 1 and imidazole for 2, respectively] with the metal(II) ions in the presence of NaOH. These complexes were characterized by FT-IR spectroscopy, thermogravimetric analysis (TG), elemental analysis and X-ray analysis. X-ray crystallographic studies of the complexes reveal that complex 1 is a double stranded one-dimensional chain, which further assembles into a three-dimensional supramolecular network via the interchain π–π stacking interaction and strong hydrogen bonds, while complex 2 exhibits a two-dimensional porous architecture. The extensively strong hydrogen bonds in complex 2 lead to the formation of three-dimensional supramolecular framework. Photoluminescence properties of the compounds 1 and 2 have been examined in solid state at room temperature. These compounds have been found to exhibit blue photoluminescence and may be good candidates for photoactive materials.

Graphical abstractTwo novel photoluminescent coordination polymers [Cd(atpt)(H2O)2] · 2H2O (1) and [Zn(atpt)(H2O)2] (2) (H2atpt = 2-aminoterephthalic acid), in which the amino group of the atpt ligand coordinates to the metal(II) ions for the first time, have been synthesized through the self-assembly reaction of H2atpt and N-containing ligands with the metal(II) ions. 1 is a double stranded 1D chain, which further assembles into a 3D supramolecular network via the interchain π–π stacking interaction and strong hydrogen bonds, while 2 exhibits a 2D porous architecture. The extensively strong hydrogen bonds in 2 lead to the formation of 3D supramolecular framework. These compounds have been found to exhibit blue photoluminescence.Figure optionsDownload full-size imageDownload as PowerPoint slide