Solvothermal Synthesis Of C-BN Nanotubes And Related Nanomaterials

Because of outstanding mechanical, electrical performance and higher oxidation resistance than that of carbon nanotubes, BN and B-C-N nanotubes are important materials and have more extensive applied foreground. The typical methods of preparation often use complex craftwork and high reaction temperature. In this work, I tried to synthesize BN and B-C-N nanotubes at moderate temperature by solvothermal method. I studied the influence of reaction temperature and different catalysts on the appearances of the products. The samples were characterized by X-ray diffraction (XRD), flourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), transmission electron diffraction (TED), electron energy-loss spectroscopy (EELS), and high resolution transmission electron microscopy (HRTEM). I elucidated the growth mechanism of B-C-N nanotubes.Hexagonal multiwalled boron nitride nanotubes and nanorods were successfully synthesized using different catalysts at moderate temperature by a benzene-thermal method using NH4Cl and NaBH4 as the reactants. The reaction could not take place below 350℃, and the products derived at 400℃and 550℃were basically the same as that prepared at 480℃. Good-shaped BN nanorods were produced using Co/Fe(C5H5)2 as catalyst. The catalyst of Ni/ Fe(C5H5)2 was not favorable to the production of BN nanorods and nanotubes. KBH4, NH4Cl and benzene were used as the source of boron, nitrogen and carbon source by a new benzene-thermal approach in a N2 atmosphere at 400℃,480℃and 550℃. Zn derived from the reduction of ZnBr2 acted as catalyst. Transmission electron microscopy investigations indicated that B-C-N nanotubes, nanospheres and a new form of carbon regular hexagonal nanocages were successfully prepared at 480℃; Carbon cubic nanorings, spherical nanocages and bad-shaped B-C-N nanotubes were produced at 550℃; I obtained a variety of B-C-N nanotubes which were not good in shape at 400℃. Combined with characterization results and related experiments, I surmised the formation mechanism of B-C-N nanotubes in which Zn acted as catalyst played critical role in the reactions.BCN single crystal nanomaterial, carbon giant fullerences and nanorods were successfully synthesized using Ni as catalyst at 500℃by a benzene-thermal method. CH3CN was used as nitrogen source, carbon source and solvent, and BBr3 was used as boron source.