The Modification Of Polyoxometalates By Copper And Silver Coordination Polymers

In this thesis, a series of organic-inorganic hybrid materials with interesting architectures have been obtained by the assembly of polyoxometalates （POMs）, different organic ligands and metal cations. We have investigated that the reaction conditions, such as the length of the organic ligands and the ratio of reactants, could affect the structure of the products. Further, some of the properties of the compounds have been investigated, and the relationships between structures and properties for these new compounds are studied.Herein, twenty-seven POM-based organic-inorganic hybrids have been synthesized by hydrothermal and water solution synthesis methods. These compounds have been structurally characterized by elemental analyses, IR, TG, XRPD and single crystal X-ray diffractions. Further, some of their properties, such as electrochemical properties, photoluminescence properties and antibacterial properties have been studied.1. Ten new orgainic-inorganic hybrid compounds based on Keggin polyanions, flexible organic ligands and metal cations have been synthesized under hydrothermal conditions: （bix）[Cu^I（bix）]₃[PW₁₂O₄₀]·4H₂O （1） [Cu^I（bix）]₃[PMo₁₂O₄₀] （2） [Hbix][Cu^I（bix）]₃[SiW₁₂O₄₀]·4H₂O （3） [Cu^II（H₂O）（Hbix）₂（bix）]₂[Cu^II（H₂O）₂（Hbix）₂（bix）][SiW₁₂O₄₀]₃·4H₂O （4） [Cu^I（bbi）]₄[SiW₁₂O₄₀] （5） [Cu^II（bbi）₂]₂[SiW₁₂O₄₀] （6） [Na（bie）]₂H[PW₁₂O₄₀] （7） [Cu^I（bie）]₄[SiW₁₂O₄₀] （8） [Cu^I（bie）]₃H₂[H3W₁₂O₄₀] （9） [Cu^I（bbi）]5H[H₂W₁₂O₄₀] （10）In compounds 1-6, polyanions act as templates directing the arrangement of the metal-organic coordination polymers. Compounds 1 and 2 are synthesized under similar conditions, but different polyanions induce the formation of distinct structures. For compounds 3 and 4, their reaction conditions are same except the ratio of the organic ligands and the Cu2+. It is known that the organonitrogen can act as not only ligands but also reductants under hydrothermal conditions, which reduce Cu2+ to Cu+. The different coordination modes of Cu2+ and Cu+ result in the distinction of the structures. Compounds 5 and 6 have the same appearance. Through the adjusting of the polyanions and metal cations, compounds 7?9 with increasing dimensions have been obtained. Compound 10 represents the first interpenetrating network based on the isopolytungstate.2. Seven hybrid compounds based on the Wells-Dawson POMs, different flexible organic ligands and metal cations have been obtained under hydrothermal conditions: （bix）[Cu^I（bix）][Cu^I2（bix）₂(P₂W₁₈O₆₂)]·2H₂O （11） [Cu^I（Hpbi）₂]₄[P₂W₁₈O₆₂]₂ （12） （H₂bbi）₄[Cu^I2（bbi）（Hbbi）₂](P₂W₁₈O₆₂)₂ （13） Ag7（bbi）5（OH）(P₂W₁₈O₆₂) （14） K_2.8Na_3.2Ag₇（bix）10（OH）(P₂W₁₈O₆₂)₂·H₂O （15） Ag₁₀K₃Na₄H（H₂bie）₂（Hbie）₂（bie）12(P₂W₁₈O₆₂)₄·8H₂O （16） Ag6KH（Hpbi）₂（pbi）₂（μ3-O）₂(P₂W₁₈O₆₂) （17）Compound 11 represents the first polypseudo-rotaxane structure based on the Wells-Dawson polyanion. In compounds 12 and 13, the polyanions acting as templates direct the formations of their supramolecular frameworks. Compounds 14?17 have the specialty of Ag?Ag interactions.3. The polyoxovanadates has been chosen as inorganic building blocks, and a new compound has been obtained under hydrothermal condition: [Cu^I4（bix）3V4O12] （18）Conpound 18 shows a 2D“sandwich”layer structure, the layers interdigitate each other by the hydrogen bonds to form a 3D supramolecular interdigitated architecture.4. In this part, different kinds of polyanions (Lindqvist type W6O192-, Keggin type SiW₁₂O₄₀₄- and PW₁₂O₄₀3-, and Wells-Dawson type P₂W₁₈O₆₂₆-) have been adopted to combine the Ag–H₂biim syatem. Four hybrid compounds have been obtained under hydrothermal conditions: Ag2（H₂biim）₄（W6O19）·2H₂O （19） Ag6（H₂biim）₆(SiW₁₂O₄₀)（OH）₂·2H₂O （20） Ag6（H₂biim）₆(PW₁₂O₄₀)（OH）3·H₂O （21） Ag6（H₂biim）₆(P₂W₁₈O₆₂)·12H₂O （22）In compound 19, W6 polyanion combines with the chelate Ag–H₂biim complex forming a discrete“dumbbell-like”motif. There exist infinite Ag chains in compounds 20–22, which are quite unusual in POM-based compounds. In compound 22, the Wells-Dawson polyanions array in a drop-down fashion, which result in the similar 2D layer as in compounds 20 and 21.5. In this part, the L-histidine has been adopted to modify the Anderson type polyanions. Because the Anderson polyanions are easily obtained in water solution and the good solubility of the L-histidine, we have chosen the water solution synthesis methods and have synthesized five new compounds: [Cu^II（C₆H₈N₃O₂）（C₆H₉N₃O₂）（H₂O）₂][Na（H₂O）₂]₂[Al（OH）₆Mo₆O₁₈]·6H₂O （23） [Cu^II（C₆H₈N₃O₂）（C₆H₉N₃O₂）（H₂O）₂][Na（H₂O）]₂[Cr（OH）₆Mo₆O₁₈]·3H₂O （24） [Cu^II(C₆H₁₀N₃O₂)（C₆H₉N₃O₂）（H₂O）₂][Al（OH）₆Mo₆O₁₈]·9H₂O （25） H（C₆H₉N₃O₂）₂[Mn（H₂O）₂][Al（OH）₆Mo₆O₁₈]·6H₂O （26） (C₆H₁₀N₃O₂)₂[Ag（H₂O）₂][Cr（OH）₆Mo₆O₁₈]·6H₂O （27）In compounds 23 and 24, the sodium cations play a connection role in the constructing of the 2D layers. When the reactant without sodium cations is chosen, a discrete compound 25 is obtained. When the transitional metal cation is changed, compounds 26 and 27 are obtained. Both the compounds show 1D chain-like structure, the histidine molecules array among the chains.