Synthesis, Crystal Structure And Properties Research Of Polyoxometalate Of Architectural Unit {P₄Mo₆}-based

Under hydrothermal condition and {P4Mo6} group as the basic building units,synthesized eight kinds of novel structure of the compound in the case of controlling thereaction conditions. And characterized by element analysis, thermal gravimetricanalysis and single-crystal X-ray diffraction:(H2en)2[{Cd(H2O)}2{CdMoV12O24(OH)6(HPO4)4(PO4)4}]4H2O4H3O (1),(Hbim)2(bim)[CdMoV12O24(OH)6(H2PO4)6(HPO4)2]18H2O (2),(Hbim)3(H2bim)0.5[{Mn(H2O)3}2{MnMoV12O24(OH)6(H2PO4)2(HPO4)4(PO4)2}]7H2O(3),[{Cd(Hbim)(H2O)}2{Cd(bim)(H2O)}{Cd(H2O)}3{CdMoV12O24(OH)6(HPO4)2(PO4)6}]4H2O(4)(en=ethylenediamine, bim=biimidazole)(Hbim)[{Na(H2O)2}{Zn(H2O)2}{NaMoV12O24(OH)6(HPO4)2(PO4)6}]8H2O(5)(Hbim)4[{NaZnMoV12O24(OH)6(H2PO4)4(HPO4)2(PO4)2}{ZnMoV12O24(OH)6(H2PO4)6(HPO4)2}]8H2O(6)(Hbim)4[{NaNiMoV12O24(OH)6(H2PO4)4(HPO4)2(PO4)2}{NiMoV12O24(OH)6(H2PO4)6(HPO4)2}]5H2O(7)(Hbim)4[{MnCdMoV12O24(OH)6(H2PO4)4(HPO4)2(PO4)2}{CdMoV12O24(OH)6(H2PO4)6(HPO4)2}]3H2O(8)These new compounds are structurally characterized by IR and single crystal X-raydiffractions. Single-crystal X-ray structural analysis reveals that compounds1–4aremononuclear transition metal-ligand {P4Mo6}-based polyoxometalatecompounds,which are composed of transition metals, organic amine ligands and{P4Mo6}-based. Compound1shows a complex3D inorganic framework withinteresting channels. Compound2exhibits3D supramolecular networks by hydrogenbonding interactions. Compound3contains two similar alternately connected chains,which further give rise to a3D supramolecular structure. In Compound4, the2Dnetwork is composed of hexa-nuclear cadmium subunits and Cd{P4Mo6}2clusters.Compounds5–8are heteronuclear metal-ligand {P4Mo6}-based polyoxometalatecompounds. In compound5, Na atoms of different coordination environments, connecting {P4Mo6}-based constitute1D chains.Adjacent chains linked with Zn atomthrough oxygen bridge to form2D layer, furthermore, layers connected to3Dframework structure. Compounds6-8are isomorphic, including two kind of M{P4Mo6}2clusters. An isolated M{P4Mo6}2cluster, the other M{P4Mo6}2clusters connected byoxygen bridge with the metal to form one-dimensional chain.By electrochemical analysis system and cyclic voltammetric, elecrrochemicalproperties of the compounds were studied in detail. And the electrocatalytic Reductionanalysis of compound are studied in detail.It indicated that showed high catalyticresponse towards the reduction of H2O2.