Design, Synthesis And Application Of One-Dimensional Tellurium Nanostructures

One dimensional nano materials, such as:wire, tube, tape and rod have been widely concerned by the scientific community because of its unique and interesting optical, electrical, magnetic, thermal and mechanical properties. The controllable synthesis of the tellurium nano material is still the problem and bottleneck in nano materials research field.Tellurium nano materials can easily react into other nano materials maintaining the same morphology. So it is still a key scientific problem to design a reasonable synthesis method to produce a unique one-dimensional Te nanostructures, and to precisely control the composition, distribution and morphology of the materials.The present dissertation will focus on the design, synthsis of unique one-dimensional (1D) Te nanostructures for the expanding applications in template synthesis and expanding applications in energy storage. One-dimensional nanomaterials with different morphologies were synthesized by different synthesis methods, and a series of other novel nanostructures were synthesized by chemical conversion method. At the same time, the growth mechanism of one-dimensional Te nanostructures is studied, and a simple and general method for controlling the morphology of nanostructures is developed. The electrical properties of the nanocrystalline silver telluride nanowires and carbon nanotubes synthesized by one dimensional Te nanostructures as templates and their applications in energy storage were further explored.The main results can be summarized as follows:1. Developing a mixed solvent method and synthesizing a one-dimensional structure with uniform morphology and size using this method. The effective control of the length and the thickness of the tellurium nano materials by adjusting the solvent component and the reaction time.2. A new technique for preparing necklace-like Silver Telluride nanowires by chemical conversion method is developed. The Silver Telluride nanowires were formed by chemical conversion method. The surface roughness of the silver nanowires can be controlled by the reaction temperature. This kind of silver nanowires is a kind of phase change material between 120 and 145, with the changing of electrical properties, so that the material can be used in the field of memory materials.3. A multifunctional flexible carbon nanotube gel was ·synthesized by hydrothermal synthesis method with Te nanowires. The complex pore structure of the composite was obtained by high temperature annealing, and the complex pore structure of the porous and 3D networks was used as the electrode material of the super capacitor and the anode materials for lithium ion batteries.4. The two kinds of based positive electrode, which are based on Te, are prepared by the combination of the above carbon nanotubes and Te nanowires, and can be directly assembled into a Li-Te battery without any binder and collector. Carbon nanotubes can not only play a role in preventing the volume change of battery between the charge-discharge process, but also have a strong adsorption of Te and polytellurides produced in the charge-discharge process, all these functions improve the battery performance. The multifunctional carbon nanotube gel can also be used in the fields of catalysis, hydrogen storage, sensor and heat insulation.