Table of Contents
ISRN Nanotechnology
Volume 2011, Article ID 684748, 8 pages
http://dx.doi.org/10.5402/2011/684748
Research Article

Growth of Vertically Aligned Carbon Nanotubes on Silicon Using a Sparked Iron-Cobalt Catalyst

1Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
2Biomedical Engineering Department, University of Wisconsin, Madison, WI 53706-1609, USA
3Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand

Received 15 April 2011; Accepted 28 May 2011

Academic Editor: I. Škorvánek

Copyright © 2011 Sirikamon Saengmee-anupharb et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Vertically aligned carbon nanotubes (VA-CNTs) were successfully grown on silicon substrates by atmospheric pressure chemical vapor deposition at 750C using acetylene as a carbon source and Fe-Co nanoparticle thin films as a cocatalyst. Preparation of the cocatalyst was operated by an economical sparking process. A small amount of water vapor was introduced into the reactor by controlling diffusion by heated water in a flask. The CNTs were characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The VA-CNTs were obtained only when the water vapor fraction in the introduced gas was in the range of 310–440 ppm. The length of the VA-CNTs reached 0.8 mm with a growth rate of 17 μm/min. Moreover, D/G-band ratio suggests that the optimum fraction of water vapor decreases defects in CNTs.