Metal [Zn(II), Cd(II)], 1,10-Phenanthroline Containing Coordination Polymers Constructed on the Skeleton of Polycarboxylates: Synthesis, Characterization, Microstructural, and CO 2 Gas Adsorption Studies

Four new coordination polymers have been obtained by the reaction of metal [Zn(II), Cd(II)], 1,10-phenanthroline separately with two carboxylic acids, [biphenyl-4,4′-dicarboxylic acid (4,4′-H 2 BDA),and 4,4′-azodibenzoic acid (4,4′-H 2 ADA)]. The crystal structures of the resulting complexes of type {[Zn(4,4′-BDA)(Phen)] 2 ·HCON(CH 3 ) 2 } n ( 1 ), {[Cd(4,4′-BDA)(Phen)] 2 ·H 2 O} n ( 2 ), {[Zn(4,4′-ADA)(Phen)] 2 } n ( 3 ), and [Zn(4,4′-ADA)(Phen)(H 2 O) 2 ] n ( 4 ) have been elucidated using their single-crystal X-ray diffraction analysis. Their thermal stabilities have been investigated using thermogravimetric analysis. Complexes result in a 2D structure with channel formation. SEM studies show a coordination-induced effect on their morphology. Grain and flowery morphology of uncoordinated ligands 4,4′-H 2 BDA and 4,4′-H 2 ADA, respectively, changes on coordination with metal salts. SEM micrographs of complexes exhibit ridged surface, cracks of 2 μm width, parallelopiped structure, and feathery appearance for 1, 2, 3, and 4, respectively. Complexes show moderate adsorption of CO 2 gas.