Soft Chemical Method For Low Temperature Synthesis Of Bn Phase Control

Nanomaterials have at least one-dimensional size in the range of nanometer scale. Materials with nanoscopic dimensions have not only technological applicatios potential in areas such as nano devices manufactory and drug delivery but also are of fundamental interests of science. The new quantumdevices based on Nano-ST are the focus of the current study of science and technology. It includes design, study and preparation of new quantum devices in the laser technology, information storage technology and operation technology. Nanotech is based on the artificial quantized structures technology, which was controlled by the quantum theory. 21th century is called as "the Era of Photo", "the Era of highly information" and "the Era of Biological Engineering", etc, but the corn of these is quantum effect. Boron nitride (BN) has many valuable merits, such as high stability, high thermal conductivity ,supreme hardness and wide band gap, etc. These merits make BN the unrivaled material for the fabrication of high temperature and high powder semiconductor devices, microwave devices, short wavelength opto-elecronic devices fabrication of super-hard protective coatings ad grinding materials. On the basis of comprehensive and thorough investigation of literatures concerning the developments of BN related composites' synthesis and applications. The author of this dissertation has obtained a sample of nearly pure cubic boron nitride (cBN) by optimizing various controllable parameters. Novel methods including structural induction method, mixed nitrogen sources method, changing the pH value of the reaction solution method and so on has been tried. Combining the experimental results and the study of the related reports, mechanisms for growing c-BN was explored. Main points of these may be summarized as follows:1. A novel structural induction method has been developed to synthesize BN nanocrystals in benzene solution. cBN and oBN were prepared by appling cubic structural nano GaP and Ni as revulsant at solvothermal condition. The experimental results show that ,the species , molar ratio of reactants and reaction temperature were very key factors influencing the phase distribution. The nucleation and growth of cBN nanocrystals were analyzed applying the heterogenous nucleation theory.2. Based on the commonness of the nitride synthesis, the mixed nitrogen sources—...