Metal-organic frameworks (MOFs) constructed from Zn-II/Cd-II-2,2 '-bipyridines and polycarboxylic acids: Synthesis, characterization and microstructural studies

摘要

Metal-organic frameworks with the compositions [Zn(bpy)(bdc)(H2O)](n) 1, [Zn(bpy)(btec)(1/2)(H2O)](n) 2, [Cd(bpy)(bdc)(H2O)](n) 3 and [Cd(bpy)(btec)(1/2)(H2O)](n) 4 (H(2)bdc = 1,4-benzenedicarboxylic acid = terephthalic acid, H(4)btec = 1,2.4,5-benzenetetracarboxylic acid and bpy = 2,2'-bipyridine) have been synthesized and characterized using spectroscopic and single-crystal X-ray diffraction techniques. In these complexes, Zn-II/Cd-II-2,2'-bipyridine units and carboxylate anions exists as nodes and spacers respectively. An infinite 1D zig-zag chain structure is observed for both complexes I and 3, whereas complexes 2 and 4 display a 3D supramolecular architecture. The complexes are found to be photoluminescent, porous and show significant thermal stability.