脉冲激光溅射下固液界面生长的碳纳米管及其机理初探

以脉冲激光束直接溅射浸在水中的单质碳样品，发现在固液界而也能产生碳纳米管．实验还发现碳纳米管的形成与样品的结构有密切的关联：石墨的层状结构越完整，碳纳米管的形成越容易，而且石墨层而相对于激光束的取向也会显著地影响碳纳米管的生成．通过对实验结果的分析，探讨了激光液相溅射产生碳纳米管的机理，认为激光溅射产生的碳蒸气被水束缚在固液的界而内，而完整的晶而使碳蒸气在界而内的分布具有准二维的性质，为碳纳米管的生长提供了较为理想的环境．

Production of Carbon Nanotubes at Carbon/Water Interface by Pulsed-Laser Ablation

Carbon nanotubes have been produced by laser ablation of graphite sample immersed in water. The experiment reveals the dependence of nanotube production on the structures of the sample. The more perfect the layer structure of the graphite sample is the easier is the production of the carbon nanotubes. Production of the carbon nanotllbes is also affected by the orientation of the lattice surface of the graphite sample. Glassy carbon cannot produce nanotube at all. Based on careful analysis of the experimental results, mechanism for the production of carbon nanotubes on the carbon/water interface is suggested. Water on the sample quenches the laser-vaporized species on the surface of the sample so as to provide the reactive material for the growth of the nanotubes. The perfect crystal lattice on the graphite sample surfhce can distribute the vaporized material to be nearly two-dimensional and the environment favorites the production of the carbon nanotubes.