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Control of the Diameter and Chiral Angle Distributions during Production of Single-wall Carbon NanotubesMany applications of single wall carbon nanotubes (SWCNT), especially in microelectronics, will benefit from use of certain (n,m) nanotube types (metallic, small gap semiconductor, etc.). However, as produced SWCNT samples are polydispersed, with many (n,m) types present and typical approximate 1:2 metal/semiconductor ratio. It has been recognized that production of SWCNTs with narrow 'tube type populations' is beneficial for their use in applications, as well as for the subsequent sorting efforts. In the present work, SWCNTs were produced by a pulsed laser vaporization (PLV) technique. The nanotube type populations were studied with respect to the production temperature with two catalyst compositions: Co/Ni and Rh/Pd. The nanotube type populations were measured via photoluminescence, UV-Vis-NIR absorption and Raman spectroscopy. It was found that in the case of Co/Ni catalyst, decreased production temperature leads to smaller average diameter, exceptionally narrow diameter distribution, and strong preference toward (8,7) nanotubes. The other nanotubes present are distributed evenly in the 7-30 deg chiral angle range. In the case of Rh/Pd catalyst, a decrease in the temperature leads to a small decrease in the average diameter, with the chiral angle distribution skewed towards 30 o and a preference toward (7,6), (8,6) and (8,7) nanotubes. However, the diameter distribution remains rather broad. These results demonstrate that PLV production technique can provide at least partial control over the nanotube (n,m) populations. In addition, these results have implications for the understanding the nanotube nucleation mechanism in the laser oven.
Document ID
20090001910
Acquisition Source
Johnson Space Center
Document Type
Conference Paper
Authors
Nikolaev, Pavel (Engineering Research and Consulting, Inc. Houston, TX, United States)
Holmes, William (Engineering Research and Consulting, Inc. Houston, TX, United States)
Sosa, Edward (Engineering Research and Consulting, Inc. Houston, TX, United States)
Boul, Peter (Engineering Research and Consulting, Inc. Houston, TX, United States)
Arepalli, Sivaram (Engineering Research and Consulting, Inc. Houston, TX, United States)
Yowell, Leonard (NASA Johnson Space Center Houston, TX, United States)
Date Acquired
August 24, 2013
Publication Date
December 1, 2008
Subject Category
Inorganic, Organic And Physical Chemistry
Meeting Information
Meeting: 2008 MRS Fall meeting
Location: Boston, MA
Country: United States
Start Date: December 1, 2008
End Date: December 5, 2008
Sponsors: Materials Research Society
Funding Number(s)
CONTRACT_GRANT: NNJ05HI05C
CONTRACT_GRANT: SAAAT07021
Distribution Limits
Public
Copyright
Public Use Permitted.

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