| The design and synthesis of functional inorganic-organic hybrid materials hasalways been an important branch of research in the field of materials science.Selecting and adjusting the composition and proportions of the inorganic componentsand organic components in the inorganic-organic hybrid materials have determinedthe final performance of the obtained hybrid materials. Polyoxometalates (POMs),polynuclear metal complexes and coordination polymers as typical subclass ofinorganic-organic hybrid materials have become a hot topic in the current research.In this thesis, we choose the typical inorganic-organic hybrid materials includingthe polyoxovanadates, polynuclear cobalt complexes and coordination polymers asour research. Using the hydrothermal/solvothermal synthesis method to prepare aseries of novel inorganic-organic hybrid compounds, we have discussed theirsynthesis conditions, crystal structure and prosperities in detail.In the introduction section, firstly, we review the basic principles, the maindirection of research and the latest research progress of the polyoxovanadates andpolynuclear cobalt complexes. Secondly, we introduce the research progress of thepillar strategy to build two-dimensional double layer structure and three-dimensionalcoordination polymers by some latest examples. Finally, we indicate the purpose andsignificance of this thesis and give an overview of the main obtained results.POVs as inorganic building blocks to build inorganic-organic hybrid compoundswith novel properties are one of important directions in the current POMs chemistry.In chapter two, using in-situ formed Mn-teta complexes and substituted Ge elements,two novel inorganic-organic hybrid compounds,[Mn(teta)][Mn(teta)(H2O)2]2{V18O42(Cl)}·8H2O (1) and [H6Ge6V6VV9IVO48(H2O)]·6(1,6-DAH)·21H2O (2) havehydrothermal synthesized and characterized. The framework of1is the first examplewhich possesses a novel2-D planar sql network comprised of a well known{V18O42(Cl)} clusters as node and two Mn(II) complexes of [Mn(teta)] and[Mn(teta)(H2O)2] as single or double μ2-bridging linkers, respectively. Single crystalX-ray diffraction structure analyses show that2is the first mixed valence[H6Ge6V15O48(H2O)] cluster with heart-like shape derived from the spherical {V18O42} archetype. The magnetic study shows that there exist antiferromagnetic interactionswithin compound1and2.Polynuclear metal clusters have attracted much attentions, not only for theirmolecular structure at the nanometer scale showing the microscopic quantumproperties different from the traditional magnetic materials, but also for potentialapplications in the fields of high-density information storage materials, quantumcomputers and magnetic refrigeration. In chapter three, choosing the rigid8-hydroxyquinoline (HQ) as ligand, various cobalt salts and different reactionsolvents, three polynuclear cobalt complexes [Co10(Q)12(μ6-CO3)4]·2.5DMF (3),[Co4(Q)8](4),[Co4(Q)6(OAc)2](5) and a {Co4} cluster-based coordination polymer[Co4(Q)6(cam)2](6) have been prepared. Compound3has an approximatesupertruncated tetrahedral geometrical shape and the largest aggregate in metal-Qcoordination chemistry to the best of our knowledge. Those in situ formed CO32-anions play a crucial role in the formation of this decanuclear cobalt(II) cluster. Themetallic skeleton in3has the adamantane topology as two nodal (2,3) with pointsymbol {63}2{6}3, which is first observed in the polynuclear cobalt complexes. Themagnetic study shows that there exists AF interaction within3. All of compounds4,5and6possess the same {Co4Q6} structural units and differ in the coordinationgeometries of Co outer sites controlling by anions (Q in4and OAc-in5) or organicligands (cam in6). The Co(II) sites in compounds4adopt the fully six-coordinatedmodes, while the mixed five-and six-coordinated cobalt(II) sites are found in5and6.The high flexible coordination ability of this dicubane cores are key to obtain thoseabove compounds. The magnetic properties studies for compounds4,5and6indicatethat all the compounds present intra-cluster dominant AF interactions. Moreover, thesimilar systems of dicubane-like Co(II) complexes involving the oxygen atoms asμ3-bridge have also been examined in relation to several structural parameters. Thesuccessfully chemical control of the coordination environments of Co(II) sites in theflexible {Co4} unit by small anions or organic linkers without changing the mainstructure may supply an applicable route to manipulate the magnetic properties.In chapter four, taking double ligands synthetic route with5-amino-isophthalicacid (aip) as the rigid ligand and1,3-bis (4-pyridyl) propane (bpp) as pillar ligand, aseries of coordination polymers have been prepared with different cobalt salts,solvents and hydrothermal reaction conditions. A novel2-D pillared-bilayer porouscoordination polymer,[Co2(aip)2(bpp)(H2O)]·5H2O (7) has been characterized bypowder XRD, TGA and IR spectroscopy. Single-crystal X-ray diffraction analysis shows that this2-D framework constructs by two distinct Co-aip layers motifs andbpp as pillar. One feature is that3-D suparmolecular architecture form by complexpi–pi interaction within innerlayer and interlayer and exhibit1-D channel. In addition,7has a higher thermal stability, the skeleton can be stabilized to300°C to remove theguest water molecules and coordinated water molecules can form a stable dehydratedproducts (7'), gas adsorption studies have shown that7' has a good separated abilityon CO2/N2.Above all, we have obtained the synthesis disciplines and reveal the intrinsicrelationship between the components and properties basing on the detailed discussionsof the synthesis factors. It has provided experience and experimental basis for thedesign and synthesis of inorganic-organic hybrid materials with novel topology andproperties. |
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