Synthesis of single‐walled carbon nanotubes with the laser vaporization method: Ex situ and in situ measurements

Abstract

In situ measurements were executed in the continuous wave CO 2 -laser vaporization synthesis of singlewalled carbon nanotubes (SWCNTs). The results were compared with the findings of the ex situ analysis of the product. Different catalysts (Co, Ni, Co/Ni, Ni/Y and Co/Y) were used and the temperature of the target surface (T s ) changed to compare the efficiency of the synthesis process. Our main results are related to the SWCNTs diameter which is depending on T s and on the catalysts nature. The targets containing Y with Co or Ni atoms produce more and larger SWCNTs than Co/Ni targets. The SWCNTs' diameter is seen to increase with T s .

Nanoparticles in analytical laser and plasma spectroscopy – a review of recent developments in methodology and applications

“…181 Similarly to the monitoring of ames, CARS, LIF, and LII have been employed for the in situ monitoring of temperature, intermediate concentration, as well as the assessment of the particle formation process. 182 In a similar, laser-based particle generation scheme, the applicability of in situ LIBS has also been demonstrated to monitor the properties of the generated particles. Picard et al employed aerodynamic focusing of the NPs under vacuum in order to eliminate the contribution of the background gas from the LIBS spectrum.…”

Carbon nanotube synthesis: from large-scale production to atom-by-atom growth

“…The value of this method is that it lends itself well to the implementation of diagnostics and in situ observations during the growth of nanotubes. Such studies allowing the collection of several instructive data were made, for example, in the group of D B Geohegan (pulsed laser vaporization) [31] and in France at the ONERA in Châtillon (continuous laser vaporization) [32]. [31] is shown below, which shows (false-color) images of the laser plasma (t < 200 µs) and Rayleigh scattering images of the plume (t > 200 µs) (scale in cm at right) versus time (log scale), the species detected spectroscopically from the plasma emission or laser-induced luminescence spectra, plume temperatures measured through black body emission above the oven temperature and lengths measured from post-growth characterization.…”