Preparation And Properties Of Organic/Inorganic Composite Materials Base On Terpyridine Derivatives

With the rapid development of modern information technology, the optoelectronic functional materials are widely used in the field of photonics technology. The optoelectronic functional materials, which can carrier storage and transmission information, are based on photon and electron carrier. Among, these, the optical functional organic/inorganic hybrid materials usually show superior collective performance. Therefore the design of functional organic molecules shows attractive prospect in building functional complex, organic-inorganic nanohybrid, self-assembly materials and optimizing the optical properties. Terpyridine and its derivatives, which contain three N atoms, have excellent optoelectronic properties. They can coordinate with transition metals, and are easy to prepare organic/inorganic hybrids. Thus, they are widely used in many fields.The current survey on optoelectronic functional materials in international material field is reviewed in the dissertation. Three novel ligands (L1, L2 and L3) containing terpyridine group and two complexes (L1+ZnS and L1+CdS) have been synthesized and characterized. Sol-gel phenomenon appeared in L2/AgNO3 system. The linear optical properties of the synthesized compounds have been investigated experimentally. The main researching contents are as follows:1.2,2':6',2"-terpyridine precursor with coordination function was synthesized through environmental friendly method (Michael reaction and Aldol condensation in water phase), which was then used as electron acceptor unit to prepare three D-Ï€-A type (D = Donor, A= Acceptor) terpyridine derivatives L1, L2 and L3 with asymmetric dipole through solvent-free Wittig reaction. Two complexes L1+ZnS and L1+CdS were obtained through solvothermal method. The ligands and the complexes were characterized through FT-IR,1H NMR, 13C NMR, mass spectrometry and elemental analysis.2. Making use of tridentate chelating ability and the large steric effect of L1,Cd(II) mononuclear complex L1+CdS was obtained. CdS nanoparticles was used as both sulfur and cadmium source. The complex contained disulfide end group. The S-1 oxidation state of sulfur was found in the complex. The density functional theory calculation indicated the excitation from HOMO of metal atom to LUMO of the ligand, which revealed typical intramolecular charge transfer from donor to acceptor. The LUMO orbital of the complex was focused partly on Cd atom, and completely transferred to the ligand until the LUMO+1 orbital, which may due to the heavy atom effect of Cd atom.3. Optical properties of L1, L2, L3, L1+ZnS and L1+CdS wre studied by UV-Vis absorption spectroscopy and single-photon fluorescence spectroscopy. The results showed that partly quenched emissions occurred when metal ions were introducded. The optical properties of the ligand and complexes in organic solvents with different polarity are explaned reasonable. The photon fluorescence quantum yield of the three ligands were greater than 0.1, indicating that they all had some value in application.4. L2/AgNO3 system tended to form sol/gel in ethanol solution. The possible formation causes of the gelatin were proposed through a series of comparative experiments. The gelatin was characterized through the X-ray powder diffraction, scanning electron microscopy and high resolution electron microscopy. The optical properties of gelatin were studied by UV-Vis and single-photon fluorescence spectroscopy.