Self-assembly And Characterization Of Organic-inorganic Hybrid Nanomaterials

Recent years, due to the increasing matching between organic and inorganic matterin structures and sizes, especially the material controllability in the range of molecularand atomic level, organic-inorganic hybrid nanomaterials gradually become the mostpromising research direction of material science. Because of the different inorganicelements and organic ligand or polymer coexisted in the system, organic-inorganichybrid nanomaterials not only have their respective nature, but will likely obtainmany special and innovative properties through the interaction between organic andinorganic matter. Meanwhile, through the applications of different reactionmechanisms, the preparation conditions as well as synthetic methods, diversemorphology of nanoporous materials, nanoparticles, nano-film materials can beproduced, which have been widely used in the optics, electricity, magnetics, catalysis,adsorption, drug delivery, bio-imaging and so on. Great attentions have been paid byworldwide researchers.However, the organic-inorganic hybrid nanomaterials with the novel structure andexcellent performance, which are synthesized by more simple and effective method,have always been the goal pursued by scientists. Molecular self-assembly technologyis the process method of the molecules spontaneously built into a stable structure andspecial shape of the aggregates, which is driven by hydrogen bonding, electrostatic,hydrophobic, lipophilic role, Ï€-Ï€ stacking. The rise of molecular self-assembly technology has provided new ideas and a improvement for the synthesis of liquidcrystals, micelles, two-dimensional film in practice.Therefore, in accordance with the above background, this thesis is committed touse a simple and effective nano-assembly technique, and successfully synthesize amesoscopic structure of the metal-organic framework materials, functionalcoordination polymer nano-crystal composite materials and surface functionalizedmetal-organic polyhedron nanocages thin film materials with ordered honeycombarchitectures. The formation mechanism, structural composition and properties havebeen investigated and major achievements have been made as following:1. Based on the known synthetic mechanism and strategies of cooperativeself-assembly, through a simple, effective, widespread hydrothermal synthesis method,coordination reaction and supramolecular interaction, through a simple, effective andwidespread hydrothermal method, the mesostructured metal-organic frameworkmaterials Cu-(5-OH-BDC)-C16have been prepared directly with the cooperativeself-assembly of Cu²⁺,5-OH-BDC and CTAC in aqueous system. This material hasshown a highly ordered hexagonal structure and a corresponding increase of unit cellsize with increase of surfactant chain length with the XRD and TEM characterization.IR spectra could prove the phenyl hydroxyl might participate in the reaction duringthe self-assembly progress and the coordination between the carboxyl and metal ionsto form frameworks of the materials. Through the analysis of ICP, HPLC, EPR, CHN,it could conclude that the chain connective construction between mononuclear Cu²⁺and ligand is the most possible structures existd in the framework with the molar ratioof Cu²⁺to ligand at1:1, and the redundant N, H element quite likely come from thenitrate and water molecules, which could play important parts in the system. TheCo-(5-OH-BDC)-C16and of Ni-(5-OH-BDC)-C16mesostructured metal-organicframework materials have also been successfully synthesized by similar syntheticmethods, which could shown a certain regularity and universality of the syntheticstrategy and method. This work well integrate the core idea in the field of mesoporousmaterials and microporous MOF materials, which make a foundation to create new and unique multi-functional nanoporous materials with a wide range of practicalapplications.2. The NMOF-organic hybrid materials of F127-[MOP-OH] has been obtainedthrough the MOP-OH crystal cell structure splitted and reorganized in the system ofF127methanol solution. The change of concentration of reactants can not only controlthe particle size of the nanocrystals in the composite (3nm to50nm), but adjustmorphology of the material with uniform size and good monodisperse nanospheres(200nm). The studies of Cu²⁺released rate experiment in organic solvents have shownthat the [CuL] unit structure of F127-[MOP-OH] is more solid and the Cu²⁺releaserate of the product is more slowly than [MOP-OH] crystall, which make a goodfoundation for anti-fouling coatings applications. Furthermore, compared to theoriginal crystal materials, the stability of F127-[MOP-OH] in water has been greatlyimproved. In the experiment of PZA release, the NMOF-organic hybrid material hasexhibited more stable release rate and longer drug release time, which opened up newareas of applications in biology or medicine directions.3. The surface alkylation of nanocage composite material {MOP-SO₃}-DODMAhas been successfully prepared with the anion metal-organic nanocage MOP-SO₃andcationic surfactant DODAMCl through electrostatic interaction.1H NMR shows thatDODMACl cationic side is fixed in anionic MOP-SO₃nanocages through a strongelectrostatic interaction. Due to the caculation of TG,CHN,ICP test, it could beproved that every MOP-SO₃were surrounded by about24DODMA⁺; Throughthe analysis of SAXS, UV-Vis, IR, it could conclude that MOP-SO₃nanocages in theproduct is intact hollow spherical shape (D=3.0±0.2nm) and all bond bindings ofnanocages preserved the well. With the water droplets templating method, the surfacefunctionalized MOP-SO₃nanocages film with ordered honeycomb architectures hasbeen successfully obtained. The experiments show that the MOP-SO₃nanocages arealso intact in the porous film. At the concentration of1.7mg·ml-1, a film will appearthree different pore morphology regions: alveoli-like porous domains, hexagonalporous domains and huge porous domains. The solvent evaporation rate and solute concentration play an imortant influence on the preparation of hexagonal porous films.When the particle deposition rate, solvent evaporation rate and the formation andarrangement of water droplets template are in the appropriate dynamic balance, highlyordered hexagonal arrangement films could possibly be obtained. Due to theaggregating similarity of metal-organic macroionic unit and viral capsid, theself-assembly method of metal-organic nanocages could also make a good foundationfor organization or controllability of biological macromolecules (protein, nucleic acidetc.) in biology or medicine domains.