Method for determination of nature of single-wall carbon nanotubes (SWCNTs) in a bundle prepared by chemical vapor deposition technique

Abstract

Abstract:We present a simple method to determine the nature of single wall nanotubes (SWNTs) in a bundle prepared by chemical vapor deposition technique by resonant Raman spectroscopy. The sample is irradiated with two wavelengths 633 nm from He-Ne laser and 514.5 nm from Ar + laser. The spectra were taken in backscattering geometry and theoretical calculation has been carried out at one peak position 216 cm −1 in RBM spectra. The results reveal that one third of the carbon nanotubes are metallic in agreement with the previously proposed reports. The geometrical and electronic properties of nanotubes are also discussed. Keywords: nature of nanotube in a bundle, resonant Raman spectroscopy, SWNTs Classification: New functional devices and materials References[1] S. Iijima and T. Ichihashi, "Single-shell carbon nanotubes of 1-nm diameter," Nature, vol. 363, pp. 603-605, 1993. [2] R. Saito, M. Fujita, G. Dresselhaus, and M. S. Dresselhaus, "Electronic structure of chiral graphene tubules," Appl. Phys. Lett., vol. 60, no. 18, pp. 2204Lett., vol. 60, no. 18, pp. -2206Lett., vol. 60, no. 18, pp. , 1992. Lett., vol. 86, no. 6, pp. 1118Lett., vol. 86, no. 6, pp. -1121Lett., vol. 86, no. 6, pp. , 2001.

Effect of functionalization and charging on resonance energy and radial breathing modes of metallic carbon nanotubes

“…Other typically quoted values are A = 224 cm −1 . nm, B = 14 cm −1 [12] and A = 234 cm −1 .nm, B = 10 cm −1 for SWCNT bundles in the diameter range; d = 1.5 ± 0.2 nm [14] (where B is an upshift coming from tube-tube interactions), A = 248 cm −1 .nm and B = 0 cm −1 for tubes with diameters above 0.7 nm [15], and A = 223.5, B = 12.5 for isolated SWCNTs on oxidized Si substrates [13]. An alternative RBM fit accounting for environmental effects has been proposed of the form [15],…”

Parametric dependence of current-voltage characteristics for scanning tunnelling microscope tip-carbon nanotube contact

“…The method to describe the nature of CNT in a bundle has previously been reported by the authors of this current paper [11], and in order to understand the mechanism of operation of any device, it is important to have knowledge of the nature of the CNT that is employed for the study. This report answers many questions that remained unexplained in previous published reports [1][2][3], in which approximate values of device design parameters have been used to fit the experimental data.…”