Solvent and polyoxometalate tuned cobalt supramolecular hybrids with a bis-imidazolyl-bis-amide ligand: adsorption of dyes and electrocatalytic properties

Abstract

Reactions of various polyoxometalates (POMs) in the presence of 1,2-bis(1H-imidazole-4-carboxamido)metaphenylene (L) and Co(II) gave four supramolecular hybrids, {[CoL(H2O)[β-Mo8O26]0.5]}·H2O (1), [Co2L2(H2O)4][β-Mo8O26]·4DMF·2H2O (2), [Co(HL)2(H2O)2][SiW12O40]·6H2O (3) and [Co(HL)2(H2O)2][SiW12O40]·3H2O (4), in which two different metal–organic segments are formed from L ligands and Co(II) atoms with different POMs. The hydrogen bonding interactions between these segments and the POMs are thought to be responsible for the different supramolecular structures. The adsorption activities of these hybrids toward organic dyes have been investigated, together with their electrocatalytic properties. Four supramolecular hybrids tuned by POMs and solvents have been synthesized in cobalt/bis-imidazolyl-bis-amide ligand reaction systems, displaying different adsorption activities toward dyes and electrocatalytic properties.