The Synthesis And Properties Of The Organic-inorganic Hybrid Materials Based On Polyoxometalates

Under hydrothermal condition,a series of novel organic-inorganic hybrid materials based V-capping POMs were obtained.The properties of compounds had been studied.According to their structures,they can be separated into two groups:1.Two novel 3D framework materials were constructed by using the classical Keggin-type and double vanadium-capped Keggin type polyoxometalate clusters as linking units:{H4[Ni(π-H2O)2]2[Ni(rt-H2O)2]8Ni4(Tri)24}[VⅣ12O40]2·24H20(1),and{H[Ni(π-O)2]2[Ni(rt-H2O)2]8Ni4(Tri)24}[VIⅤW10VⅤ2O40V2][VⅣW9VⅤ3O40VⅣ2]·24H20(2)(Tri = 1,2,4-triazole).Compound 1 are pillared by a typical Keggin-type POM[VW12O40]4-into 3D supramolecular framework.Interestingly,the 3D supramolecular framework in 1 was successfully transferred into 3D covalent MOF via extending length of the pillars by capping Keggin-type POM with V-0 units.Moreover,electrochemical behaviors and electrocatalytic activity of 1 and 2 were both investigated,which can act as the excellent bifunctional electrocatalysts.2.Different crystal structures can be obtained by using different heterocyclic organic ligands.In the compounds 3,[Cu4(Trz)4]4-were synthesized by Cu2+ and triazoles,which connects with[Cu2(Trz)]2+ could form metal-ring[Cu12(trz)8]4+ by Cu-C bonds.In the compounds 4,when we used pyridazine instead of triazoles,we could obtain metal-ring[Cu3O3(Pyridazine)3].Then metal-ring could be combined with capped Keggin-type POM to build hybrid material.The electrochemical study revealed that compound 3 and 4 process great electrocatalytic activity.