Effect of Temperature Gradient near the Target and Gas Flow Rate on the Diameter Distribution of Single-Walled Carbon Nanotubes Grown by the Laser Ablation Technique

AbstractGas dynamic and time resolved imaging studies have been performed on the growth of single-walled carbon nanotubes (SWNTs) in the laser ablation process. SWNTs were synthesized by laser ablation of Ni-Co catalyzed graphite targets at 1200°C under argon flow. The effects of the temperature gradient near the target and the gas flow rate were studied in order to understand the effect of gas dynamics over the diameter distribution of SWNTs. The gas flow rate affects the diameter distribution of SWNTs especially when the growth species flow through a large temperature gradient. Scattering images from the growth species at different flow rates was recorded by high-speed video imaging. The results indicate that the velocities of these species are dependent on the gas flow rate but this dependence is evident 30 ms after the laser ablation. These findings are used to estimate the time period for the nucleation and the growth of SWNTs.

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Synthesis of single-walled carbon nanotubes in an expanding vapor-gas flow produced by laser ablation of a graphite-catalyst mixture

Technical Physics ◽

10.1134/1.1626776 ◽

2003 ◽

Vol 48 (11) ◽

pp. 1436-1441 ◽

Cited By ~ 3

Author(s):

G. I. Kozlov ◽

I. G. Assovskii

Keyword(s):

Carbon Nanotubes ◽

Laser Ablation ◽

Gas Flow ◽

Single Walled Carbon Nanotubes ◽

Single Walled Carbon ◽

Walled Carbon Nanotubes

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Selective Diameter Control of Single-Walled Carbon Nanotubes in the Gas-Phase Synthesis

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.sw23 ◽

2008 ◽

Vol 8 (11) ◽

pp. 6153-6157 ◽

Cited By ~ 149

Author(s):

Takeshi Saito ◽

Satoshi Ohshima ◽

Toshiya Okazaki ◽

Shigekazu Ohmori ◽

Motoo Yumura ◽

...

Keyword(s):

Carbon Nanotubes ◽

Carbon Source ◽

Gas Phase ◽

Flow Rate ◽

Carbon Sources ◽

Single Walled Carbon Nanotubes ◽

Diameter Distribution ◽

Single Walled Carbon ◽

Diameter Control ◽

Walled Carbon Nanotubes

A novel approach for selective diameter control of single-walled carbon nanotubes (SWNTs) is performed in the gas-phase growth using two kinds of carbon sources with different decomposition properties; the one carbon source (1st carbon source) is the organic solvent which is difficult to decompose in the reactor and the another carbon source (2nd carbon source) is facile to decompose. The diameter distributions of SWNTs synthesized with various conditions of the flow rate of the 2nd carbon source were investigated by resonant Raman scattering, optical absorption, and photoluminescence (PL) mapping measurements. It was found that increasing the flow rate of the ethylene tends to decrease the diameter of synthesized SWNTs, probably due to the earlier nucleation of SWNTs induced by the ethylene addition. The controlling the flow rate of the ethylene used as a 2nd carbon source can selectively tune the diameter distribution of SWNTs in our growth system.

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Low-temperature synthesis of single-walled carbon nanotubes with a narrow diameter distribution using size-classified catalyst nanoparticles

Chemical Physics Letters ◽

10.1016/j.cplett.2006.03.017 ◽

2006 ◽

Vol 422 (4-6) ◽

pp. 481-487 ◽

Cited By ~ 57

Author(s):

Daiyu Kondo ◽

Shintaro Sato ◽

Yuji Awano

Keyword(s):

Carbon Nanotubes ◽

Low Temperature ◽

Single Walled Carbon Nanotubes ◽

Diameter Distribution ◽

Low Temperature Synthesis ◽

Temperature Synthesis ◽

Catalyst Nanoparticles ◽

Single Walled Carbon ◽

Walled Carbon Nanotubes ◽

Narrow Diameter Distribution

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Diameter-Controlled Synthesis of Single-Walled Carbon Nanotubes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.151 ◽

2013 ◽

Vol 652-654 ◽

pp. 151-154

Author(s):

Ting Kai Zhao ◽

Xing Zhao ◽

Jin Yan ◽

Li Du ◽

Tie Hu Li

Keyword(s):

Carbon Nanotubes ◽

Single Walled Carbon Nanotubes ◽

Recent Decade ◽

Diameter Distribution ◽

Future Directions ◽

Single Walled Carbon ◽

Existing Problems ◽

Multi Walled Carbon Nanotubes ◽

Synthesis Of Carbon Nanotubes ◽

Walled Carbon Nanotubes

With the technological progress in the synthesis of multi-walled carbon nanotubes and single-walled carbon nanotubes, more attention was attracted to the synthesis of carbon nanotubes with diameter distribution, ideal length, different chirality and certain orientation. In recent decade, all these factors have been investigated and a number of progresses have been made for the application of carbon nanotubes. The latest researches on the growth of diameter-controlled single-walled carbon nanotubes are reviewed and discussed. The existing problems and challenges of the synthesis processes have been addressed in the future directions.

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Selective Synthesis of Single-Walled Carbon Nanotubes by Blending Catalysts

ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference, Volume 2 ◽

10.1115/ht2007-32524 ◽

2007 ◽

Author(s):

Shuhei Inoue ◽

Takeshi Nakajima ◽

Kazuya Nomura ◽

Yoshihiro Kikuchi

Keyword(s):

Carbon Nanotubes ◽

Fermi Level ◽

Chemical Vapor ◽

Single Walled Carbon Nanotubes ◽

Diameter Distribution ◽

Efficient Catalyst ◽

Single Walled Carbon ◽

Similar Density ◽

Walled Carbon Nanotubes ◽

Diameter Distributions

Single-walled carbon nanotubes are considered the most attractive material and a lot of synthesis processes are developed. Among these synthesis processes chemical vapor deposition processes are considered to be most suitable for macroscopic production. In many CVD processes the alcohol catalytic CVD process can be the best process because it can produce very pure nanotubes without any purification. However, cobalt is essential as a catalyst that makes the flexibility of catalysts restricted. In this paper, our investigation mainly focused on as follows: The efficiency of combined catalysts with/without cobalt. The diameter distributions against catalysts density. The electrical states of catalysts near Fermi level. Consequently, almost all of cobalt containing catalysts worked well, and the diameter distributions were proportional to the particle size. Efficient catalysts had enough states around Fermi level and the cobalt-less efficient catalyst cluster model showed the similar density of state to the cobalt cluster. Thus, noticing to the DOS, other efficient catalysts can be discovered and the diameter distribution will be controllable by adjusting temperature, a catalyst size, and a catalyst combination without any complicated techniques and facilities.

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