Porous Polyoxometalate Compounds Directed By Templates

Porous polyoxometalate (POM)-based materials have attracted great attention, due to their widely applications in catalysis, adsorption and so on. Among the various synthesizing methods of these materials, utilizing templates for constructing porous structures seems to be an effective strategy, in which the final structures could be tuned through the selective of templates. In this thesis, we adopt three kinds of templates to construct different POM-based porous frameworks under hydrothermal conditions, and six POM-based porous compounds have been obtained. The influences of the templates are also discussed, and some related properties are preliminarily investigated.1. Utilizing en and dien as templates respectively, two distinct manganese molybdenum(V) phosphates with different topologies have been synthesized, and the influences of templates on the structures are also discussed: (H2en)₂{[Mn(H₂O)]2[MnMo₁₂O₂₄(OH)₆(H2PO₄)₂(HPO₄)4(PO₄)₂]}·7H₂O (1) (H3dien)₂{[Mn(H3O)₂][Mn₃Mo₁₂O₂₄(OH)₆(HPO₄)₂(PO₄)₆]}·5H₂O (2) Compound 1 shows a 3D inorganic (4, 8)-connected porous framework templated by en molecules, which is built from the sandwich {Mn[Mo6P4]2}clusters and [MnO6] octahedra. When replacing en molecules by a longer dien molecule, we obtained compound 2. It exhibits a 3D (4, 10)-connected framework with dien templates, constructing from {Mn[Mo6P4]2}clusters, two [MnO6] octahedra and eight [MnO₄] terahedra.2. Using three kinds of Keggin POM templates, three different metal-pyrazine porous coordination compounds have been synthesized: [CuI5(pz)₆Cl][HPMoVI10MoV2O₄0] (3) [Ag5(pz)7(BW₁₂O₄₀)] (4) [CuI5(pz)₆H(H2W12O₄0)]·4H₂O (5)?Compound 3 exhibits a Cu-pz-Cl double layer structure, which is templated by PMo12 anions; Compound 4 shows a 3D Ag-pz porous complex, into which BW12 anions are located; Compound 5 is a 2D Cu-pz cation layer templated by W12 anions.3. Adopting P2W18O626-, Cu ions, pz and 2,2'-bipy ligands as materials, a [Cu^Ⅱ(2,2'-bipy)₂(H₂O)]²⁺ complex-templated 3D framework has been obtained: [Cu^Ⅱ(2,2'-bipy)₂(H₂O)]3[CuI6(pz)₆(P₂W₁₈O₆₂)₂] (6) Compound 6 is a 3D P2W18-CuI-pz framework. The [CuII(2,2'-bipy)₂(H₂O)]²⁺ complex generated in situ as template locating in the voids of the framework.