We have successfully synthesized carbon nanotubes by the solvothermal approach at 400℃,in which toluene was used as the carbon source and solvent,and LaNi5 was used as the catalyst.The products were characterized with X-ray powder diffractometer(XRD),transmission eletronic microscopy(TEM)and Raman spectroscopy.The results show that the products are hexaganol phase carbon nanotubes with inner diameters ranging from 5 to 10nm and outer diameters approximately 100nm.The length of the carbon nanotube is of several micrometres.
Nickel powders were obtained after chemical reduction of nickel chloride by KBH4 using absolute ethylenediamine as solvent in a stainless autoclave. The product was characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). XRD results show that the as-prepared sample have different crystal structures at different reaction temperatures. It was face-centered cubic (fcc) nickel under 200 ℃, and there was only hexagonal close-packed (hcp) Ni above 300 ℃. At 250 ℃, the patterns indicate that both fcc and hcp phases of Ni coexist in the as-prepared sample. When the ethylenediamine was respectively substituted by benzene and toluene, only fcc phase nickel was obtained. SEM and TEM indicate that the fcc Ni is nano-particles with about 100 nm in diameter, and hcp nickel is nano-crystalline clusters.
Nano-crystalline NiO was synthesized by combustion reaction between aqueous Ni(NO3)2 and Glycin at 500℃.The crystal structure,particle size and morphology of the products were examined by X-ray powder diffraction (XRD)and transmission electron microscope (TEM).The results show that the NiO is face-centered cubic (fcc) crystal phase with average diameter of 10 nm.