| The main purpose of the work focus on design and obtain polyoxotungstate-based organic-inorganic hybrid materials decorated by 3d/3d-4f metal complexes. Fifteen new materials with novel structure have been obtained under hydrothermal methods by choosing three types of N-heterocycle ligands. Materials have been characterized by infrared spectroscopic analysis ?IR?, X-ray diffraction analysis, TG analysis, XRD and ICP. The synthetic factors such as pH, ratio of starting materials, kinds of POMs, which influence on the structure of the compounds, are researched. Furthermore, electrochemical and magnetic properties of part materials are discussed.1. By using 1,3,5-tris?1-imidazoly?benzene ?tib?/3,5-bis?1-imidazoly?pyridine ?bimpy? as ligands and the Keggin/Dawson type polyoxotungstates as reactants, six unreported new materials based on polyoxotungstates were obtained by using hydrothermal conditions.[Cu2?Htib?2?a-SiW12O4o?] ?1?[Cu2?Htib?2?H2tib?2?H2O?4(a-HBW12O40)2]·8H2O ?2?[Na4?tib?2?H2O?2(a-HBW12O40)]·2H2O ?3?[Cu2?H2tib?4?H2O?2(a-HP2W18O62)2]·14H2O ?4?[Cu3?bimpy?3?H2O?2(a-SiW12O40)]·2H2O ?5?[Cu2?Hbimpy?2?H2O?2(a-P2W18O62)]·6H2O ?6?In compounds 1-4, tib ligand adopt ?1, ?2 and ?3 coordination mode respectively. Compound 1 shows a 3D supramolecular structure, consisting of {-Cu-tib-Cu-}n metal complex chains and a-SiW12 clusters. While compound 2 is a 3D supramolecular structrue constructed by a-BW12 clusters and{Cu2tib4} units. The 2D network structure of material 3 is featured by two moieties:an infinite{-Nal-tib-Nal-}n chain and the a-BW)2 clusters. Compound 4 consists of a-P2W18 and{Cu-tib} motifs with an infinite sinusoidal chain structure. By utilizing bimpy as a ligand and the classical POMs as inorganic building units, compounds 5 and 6 were prepared by utilizing hydrothermal methods. The a-SiW12 clusters link{Cu-bimpy}nanocages to generate a 3D framework in compound 5. In compound 6, a-P2W18 clusters link{Cu-tib} ladders leading to a 2D network. The electrochemical properties of compounds 1-6 were discussed by cyclic voltammetry.1,2,4 and 5-CPE displayed bifunctional electrocatalytic activities toward reduction of nitrite ?NO2-? and oxidation of ascorbic acid ?AA?.2. Three new organic-inorganic hybrids were obtained by using tib ligand under hydrothermal methods.[Co2?tib?2?H2O?4(a-HBW12O40)]·6H20 ?7?[Co2?tib?2?H2O?4(a-SiW12O40)]·4H20 ?8?[Co?H2tib?4(a-BW12O40)2]·8H2O ?9?Three new organic-inorganic hybrid materials based on the Keggin polyoxotungstates, were hydrothermally synthesized by utilizing a pH-dependent approach in the same Co/tib/POM reaction systems. X-ray structural analyses reveal that compounds 7 and 8 are isostructural, obtained at pH 3.6, have a ?3,4?-connected 2D net with the ?42·6??42·63·8? topology; compound 9, isolated at pH 4.8, is a "butterfly-like" structure stemming from a-BW12 polyoxoanions and{Co-tib} motifs. In addition, the electrochemistry and electrocatalytic properties of materials 7-9 were studied by cyclic voltammetry. Compounds 7-9 displayed bifunctional electrocatalytic activities toward reduction of NO2- and oxidation of AA.3. With choice of 1,2-propylene diamine ?1,2-dap? and bimpy molecules, six novel monovacant polyoxotungstate-based organic-inorganic materials were achieved.[Cu6?1,2-dap?2?H2O?][Er?a-PW11O39?2]·5H2O ?10?[Cu2.5?bimpy?2?H2O?2][Eu?H2O?3(a-SiW11O39)]·3.5H2O ?11?[Cu2.5?bimpy?2?H2O?2][Sm?H2O?3(a-SiW11O39)]·?2.5?H2O ?12?[Cu2.5?bimpy?2?H2O?2][Ho?H2O?3(a-SiW11O39)]·3.5H2O ?13?[Cu2.5?bimpy?2?H2O?2][Y?H2O?3(a-SiW11O39)]·3.5H2O ?14?[Cu2.5?bimpy?2?H2O?2][Ce?H2O?3(a-SiW11O39)]·3H2O ?15?Compound 10 possesses a 2D network featured by [Er?a-PW11O39?2]11- clusters and [Cu?1,2-dap?]2+ units, while hybrids 11-15 are isostructural, showing a 3D framework featured by{-SiW11-Ln-SiW11-}n inorganic chains and{Cu/bimpy} metal-organic ribbons stemmed from Cu<sup>2+ ions and bimpy ligands. The adjacent{Cu/bimpy} ribbons are connected by two antiparallel{-SiW11-Eu-SiW11-}n chains to create a 2D layer structure, which is extended to a ?3,4,4,4,6?-connected 3D framework with ?4·72??4·6·73·8??42·53·7??42·72·92??42·52·67·83·10? topology through the Cu-O covalent bonds. The magnetic and electrocatalytic properties of hybrids 11 and 12 have been investigated. |
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