Preparation And Synthesis Mechanism Of Te/PbTe One-Dimensional Nanomaterials

Semiconductor nanomaterial have attracted much attention in recent years,due to their unique size-dependent properties( lower electron kinetic energy and longer de Broglie wave) and promising values in photocatalysis, magnetic materials; optoelectronic and biomedical applications.IV-VI lead chalcogenides( PbX, X=S, Se and Te) are direct narrow band gap semiconductors. Due to their higher electron mobility and larger dielectric constant, these materials are mainly used in optical switch, solar cell, photodetector, electroluminescent device, optical thermoelectric device and coordinated laser. Such devices have the advantages of simple structure, low cost and high conversion efficiency. They play an important role in the realization of commercial application of electronic devices. However most of the literature-reported synthetic methods used toxic solvents or surfactants, and the serious harm to the environment. Therefore, to find a kind of green environmental friendly, preparation method of high efficiency and low energy consumption has important scientific significance and application value.The master’s thesis mainly focuses on lead telluride. PbTe nanomaterials were prepared by two steps of the liquid phase synthesis method. Through adjusting some parameters in the reaction process, the morphology of these nanomaterials are controlled. At last we studied the growth mechanism of nanomaterials and put forward some reasonable conjecture for the growth process. The main contents are as follows:(1) The preparation of Te\PbTe nanomaterials was explored by solvothermal method, by changing of their morphology and growth rate under different solvents, reducing agents and surfactants.(2) A green synthetic route is proposed to preparation PbTe nanomaterials. Highly uniform and dispersed PbTe nanorods were prepared, by using glucose as reducing agents. Production is high and easy to synthesize. The structure and morphology of the prepared samples were characterized by X ray diffraction(XRD),scanning electron microscope(SEM), transmission electron microscopy(TEM),high resolution transmission electron microscopy(HRTEM) and energy dispersive spectrometer(EDS). The optimal reaction conditions for the synthesis of PbTe nanorods were obtained.(3) High quality spherical PbTe nanoparticles were prepared by changing the reaction order of the precursors. And the formation mechanism was analyzed.