Production of diamond nanospherulite at carbon-water interface by laser ablation and its characterization by TEM
- 化学化工－已发表论文 
Carbon nanoparticle appearing in perfect spherical shape, with sizes varying from tens nanometers to several micrometers, can be produced by pulsed-laser ablating different elementary carbon samples immersed in water. A variety of samples including HOPG, graphite, aredischarging deposite, glassy-carbon and imitation-diamond have been tried. The yield of the diamand nanospherulite is found to depend on the structure of the sample. The SAED pattern of the carbon-sphere produced from are-discharging deposite can be attributed to the hexagonal structure of diamond, and its HREM image exihibits 0.38 nm x 0.31 nm lattice, which is just three times of the distances for (110) (d = 0.126 nm) and (004) (d = 0.1030 nm) crystal layers of hexagonal diamond, respectively. While the SAED pattern from glassy-carbon sample displays a cubic-diamond structure. Furthermore, Raman spectra and C-13 NMR indicate tetrahedral network of the spheres.