Study On The One-Step Solution-Based Synthesis And Properties Of Core-Shell Structure Nanocomposite

As a new kind of material, core-shell structure nanocomposite materials have become the focus of intensive research owing to their distinctive geometries, novel properties, and potential applications. In this dissertation, based on the intrinsic properties of substances, rational one-step solution routes have been successfully designed to synthesize of core-shell nanocomposite. The formation process of the as-prepared core-shell nanocomposites was investigated, which enriched and developed the solution-based synthesis approach of nanomaterials. The as-prepared core-shell nanocpmposites are potentially useful in different applications to check their properties and performances. The main contents can be summarized as follows:1. A novel polymer-assisted hydrothermal route is designed for the one-step synthesis of Ag/C core-shell coaxial nanocables. In the reaction system, CCl₄ was added for controlling reaction process, and the presence of poly (ethylene glycol) (PEG) is significant to assisting the anisotropic growth of silver nanowire cores and the formation of a homogeneous reaction system. The as-prepared Ag/C core-shell nanocables exhibit good flexibility.2. On the basis of the intrinsic properties of substances, a one-step solution route is designed for the fabrication of one-dimensional single-crystal semiconductor/carbon core-shell nanocomposite with selenium (Se) or tellurium (Te) as core. The as-prepared Se/carbon core-shell nanocomposite can be used as templates to fabricate carbon submicrotubes at room temperature. The formation process of as-prepared one-dimensional semiconductor/carbon core-shell nanocomposite was investigated in detail. The results of the investigation and further experiments confirm that the size of the products could be easily tailored by controlling the experimental conditions. The as-synthesized one-dimensional semiconductor/carbon core-shell nanocomposite and the carbon submicrotubes are expected to find potential application in nanodevices and biomedicine, among other fields. 3. A hydrothermal route is employed to synthesis well-dispersed poly (furfuryl alcohol) (PFA) nanospheres by polymerizing organic monomer. The different morphologies of PFA could also be obtained via adjusting the reaction conditions. Based on the investigative results of the formation process of PFA nanospheres, it can be concluded that poly (vinyl pyrrolidone) (PVP) molecule acts as a control agent for restriction the polymerization process of furfuryl alcohol FA. PFA nanospheres can be obtained only when the polymerization of FA was entirely confined by excessive PVP. Based on the investigative results and the intrinsic properties of substances, a one-step hydrothermal route is designed for the fabrication of asymmetric silver/poly (furfuryl alcohol) (Ag/PFA) nanocomposite particles. This feasible approach presented a new paradigm in the preparations of polymer nanospheres and inorganic/polymer nanocomposite.4. A facile, controllable, and low temperature (80°C) solution-phase process is designed for the preparation of ZnS nanospheres. The formation process of ZnS nanospheres was investigated, and the investigative result reveals that thiourea is used both as a sulfur source and as a capping ligand which can direct initially formed ZnS nanoparticles to aggregate into nanospheres. The as-prepared ZnS nanospheres are well dispersed, and the UV-vis absorption spectrum of the ZnS nanospheres exhibits an obvious blue shift.