Detection of nickel atom by laser induced fluorescence during carbon nanotube formation in a laser produced plume
نویسندگان
چکیده
In situ monitoring of catalyst nickel atoms by laser induced fluorescence during carbon nanotube formation in a laser-produced plume was performed at the Johnson Space Center nanotube production laboratory. The results indicate that ablation of nickel and plume dynamics are strongly related to the oven temperature. Nickel atoms have a long lifetime of several milliseconds and have an electronic temperature of at least 1500 K during carbon nanotube formation. © 2001 American Institute of Physics. @DOI: 10.1063/1.1365441#
منابع مشابه
Growth mechanisms for single-wall carbon nanotubes in a laser-ablation process
Mechanisms proposed in the literature are compared with a current scenario for the formation of single-wall carbon nanotubes in the laser-ablation process that is based on our spectral emission and laser-induced fluorescence measurements. It is suggested that the carbon which serves as feedstock for nanotube formation not only comes from the direct ablation of the target, but also from carbon p...
متن کاملInfluence of shielding gas composition on weld profile in pulsed Nd:YAG laser welding of low carbon steel
Weld area and weld depth/width ratio can be considered to be of the most important geometrical factors in pulsed laser welding. The effects of carbon dioxide and oxygen additions to the argon shielding gas on the weld properties in pulsed laser welding of low carbon steel is investigated. Presence of carbon dioxide and oxygen up to 10 and 15 percent respectively decreases the weld geometrical f...
متن کامل“ Magnetic carbon nanocluster growth in a plume formed by MHz - pulse - rate laser ablation ”
Material parameters of a solid experience a dramatic change when cluster size becomes less than a certain critical value. Hence, one can control material properties through control over cluster size. Previously we have reported a unique nanostructured carbon nanofoam, which has strong paramagnetic properties. Carbon nanoclusters produced by high-repetition-rate laser ablation of graphite and gl...
متن کاملComparison of two methods of carbon nanotube synthesis: CVD and supercritical process (A review)
A carbon nanotube (CNT) is a miniature cylindrical carbon structure that has hexagonalgraphite molecules attached at the edges. Nanotubes look like a powder or black soot, but they'reactually rolled-up sheets of graphene that form hollow strands with walls that are only one atom thick.Carbon nanotube has been one of the most actively explored materials in recent year(s) due to...
متن کاملDiagnostics of particle dynamics during optically functional thin-film deposition by laser ablation
We describe the diagnostics of the particle dynamics during nanoparticle formation by pulsed laser ablation in a background gas. First, we describe the deposition of ZnO nano-structured thin films, along with the results of Rayleigh scattering observation of ZnO nanoparticle formation in the ablation plume. Then, we propose a new imaging technique, called re-decomposition laser-induced fluoresc...
متن کامل