Synthesis And Self-assembly Studies On Nitrogen-containing Compound, Polymer, And CdS Nanomaterials

In this dissertation, a research has been made on synthesizing a supermolecular compound, three coordination polymers, microcosmic self-assembly process of the synthesized some amphiphilic molecules, and assembling nanomaterials. The main results are as follows:(1) A new bis-pyridine ligand of{2,7-dibromo-9,9-(4-pyridyl-methyl) fluorene [DBPMF]} has been synthesized and characterized. By using this ligand, a supermolecular compound of{[DBPMF H2]2+·2[C1O4]-} and three coordination polymers have been obtained, including [Cd4(DBPMF)6(SCN)8]n(1),[Cu2(DBPMF)2(CH3COO)5·2DMF]n(2) and [Cd(DBPMF)(acac)2]n(3). In the{[DBPMF H2]2+·2[C1O4]-}, four kinds of supermocular interactions of N-H…O hydrogen bond, C-H…O potential hydrogen bond, C-H…π interaction and π…π packing interaction have been found. Among these supermolecular interactions, two types of N-H…O hydrogen bonds join two [DBPMFH2]2+cations and two [ClO4]-anions together to form an one-dimensional chain. In the complex1, each ligand coordinates with two Cd2+ions to construct a coordination polymer with intersectant and helix configuration, which finally presents a flower-like hollow structure along the b axis. In the complex2, each ligand also links with two metal ions of Cu2+which results in the interlinkage of two complex units. Ultimately, two kinds of1D chains have been found, one is based on Cu(1) unit and another is based on Cu(2) unit. In the complex3, each of acetylacetone cadmium(II) unit is combined by the bis-pyridine ligand of [DBPMF] to build an infinite1D chain.(2) We present investigations on microcosmic self-assembly process of the synthesized amphiphilic molecules (DMAPNPP). During the temperature of the amphiphilic molecules’ saturated solution drop and the solvent evaporation, the amphiphilic molecules were firstly assembled into thinner belt-like arms which extending from a core. Secondly, the curled belts did not only served as a template, but also were straight as the subsequently assembly. This conclusion can best illuminate why the size can be controlled by adjust amphiphilic molecules deposition velocity in their saturated solution. And which opens a new venue for conveniently adjusting the self assembly dimension of the similar amphiphilic molecules.(3)1-(N-butyl-1,8-naphthalimide-4’-yl)-3-(4-methoxyl-phenyl)-5-phenyl-pyrazoline (BMPP)/polyaniline core-shell nanofibers were synthesized by in situ chemical oxidative polymerization of aniline using BMPP nanofibers as template. BMPP/polyaniline core-shell nanofibers exhibited uniform fibrilliar morphology and possessed BMPP nanofiber core and polyaniline shell, which existed in the form of nanoparticles. BMPP nanofibers were fabricated by the modified reprecipitation method with water as poor solvent. After BMPP/polyaniline core-shell nanofibers were washed with ethanol as good solvent to remove BMPP cores, polyaniline nanotubes with netlike structures were obtained. The molecular structures of BMPP/polyaniline nanocables were characterized by Fourier transform infrared spectroscopy and UV-vis spectroscopy, respectively. The core/shell structures of BMPP and polyaniline endowed BMPP/polyaniline core-shell nanofibers good electrochemical properties in comparison with BMPP nanofibers.(4) Se/polypyrrole nanostructures were successfully synthesized using sodium selenite as initiator by chemical polymerization of pyrrole. EDS spectrum shows that the resulting products is consist of selenium, carbon, and nitrogen, which further conforms the Se/polypyrrole composite structure. The influences of synthetic parameters, such as surfactants, and reaction temperature, on the morphologies and sizes of Se/polypyrrole nanostructures were investigated. Se/polypyrrole hollow microtubes have been obtained using cetyltrimethylammonium bromide (CTAB) as surfactant under hydrothermal conditions. The hollow microtube is about800nm in diameter,30nm in the thickness, and the lengths of2-3um. With the concentration of sodium selenite increased, the thickness of Se/polypyrrole hollow microtubes is gradually increasing, and the separated selenium particles in the system are obtained. However, only Se/polypyrrole nanoparticles are obtained in the absence of CTAB, which shows that CTAB plays an important role in the formation of Se/polypyrrole hollow microtubes. When the reaction is taken at150℃, Se/polypyrrole nanoparticles are obtained.(5) Bundle-like cadmium sulfide (CdS) nanostructures assembled by high-quality nanorods have been successfully synthesized on a large scale via a facile solvothermal route in a mixed solvent of ethylenediamine and dodecanethiol. The typical lengths of bundle-like CdS nanostructures are several tens of micrometers, and the diameters and lengths of CdS nanorods are about50-70nm and several micrometers, respectively. The influence of the concentration of dodecanethiol on the morphologies of CdS nanostructures has been investigated carefully. Photoluminescence spectra (PL) of CdS nanostructures reveal that the bundle-like CdS nanostructures exhibited two fluorescence emission peaks centered at495nm (2.51eV) and522nm (2.38eV) as the excitation wavelength is405nm.