Article

Effect of chemical treatment on electrical conductivity, infrared absorption, and Raman spectra of single-walled carbon nanotubes.

Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany.
The Journal of Physical Chemistry B (impact factor: 3.7). 05/2005; 109(15):7174-81. DOI:10.1021/jp044741o
Source: PubMed

ABSTRACT We investigate the magnitude and temperature dependence of electrical conductivity, the optical and infrared absorption, and the Raman spectra of single-walled carbon nanotube (SWNT) bucky-paper after chemical treatment and determine the correlations between the changes in these properties. Ionic-acceptor doping of the SWNT bucky-paper (with SOCl(2), iodine, H(2)SO(3), etc.) causes an increase of electrical conductivity that correlates with an increase of the absorbance in the far-IR region and an increase in the frequency of Raman spectral lines. Conversely, treatment with other molecules (e.g., aniline, PyPhF(5), PhCH(2)Br, etc.) leads to a decrease in both conductivity and far-IR absorption. The temperature dependence of the conductivity gives a good indication of the presence of metallic charge carriers and is in agreement with the model of interrupted metallic conduction.

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Keywords

absorbance
 
chemical treatment
 
conductivity
 
Conversely
 
correlates
 
electrical conductivity
 
good indication
 
infrared absorption
 
Ionic-acceptor
 
metallic charge carriers
 
metallic conduction
 
single-walled carbon nanotube
 
SWNT
 
SWNT bucky-paper