Chemical Vapor Deposition Based Synthesis of Carbon Nanotubes and Nanofibers Using a Template Method

Abstract

We have developed a new approach for preparing graphitic carbon nanofiber and nanotube ensembles. This approach entails chemical vapor deposition (CVD) based synthesis of carbon within the pores of an alumina template membrane with or without a Ni catalyst. Ethylene or pyrene was used in the CVD process with reactor temperatures of 545 °C for Ni-catalyzed CVD and 900 °C for the uncatalyzed process. The resultant carbon nanostructures were uniform hollow tubes with open ends. Increasing the deposition time converted the carbon nanotubes into carbon nanofibers. Transmission electron microscopy and electron diffraction data show the as deposited graphitic carbon nanofibers synthesized with the Ni catalyst were not highly ordered. Heating the carbon-containing membrane at 500 °C for 36 h, however, converts the carbon nanofibers into highly ordered graphite. The electron diffraction data show a spotted diffraction pattern characteristic of single-crystal graphite with the graphitic planes parallel to the long axis of the nanofibers.

Carbon nanotubes prepared by anodic aluminum oxide template method

“…One is to carbonize organic polymer (such as furfural alcohol and acrylonitrile) that was filled into the nanochannels of AAO using impregnation method [33,66,67]. The second is to deposit pyrolytic carbon from gaseous hydrocarbons (acetylene, propylene, acetonitrile, etc), which is much easier and widely used now [32,[68][69][70][71][72][73]. Typically, a gaseous carbon source is decomposed within a hot-wall tubular reactor in which the AAO film is preset.…”

Purification, Functionalization, and Bioconjugation of Carbon Nanotubes

“…In this method, CNT growth is governed by the type of hydrocarbon gas and/or catalyst used and the growth temperature. Unlike the arc-discharge and laser ablation methods, the CVD approach allows for control over the location and the alignment of the synthesized CNTs (11).…”

Nanomedicine in the diagnosis and therapy of neurodegenerative disorders

“…Nanofibers and nanotubes are carbon vapor-grown [243], self-assembled from peptide amphiphiles [244,245] or electrospun from most polymer materials [158]. Carbon nanotubes have attracted attention in nanomedicine although there are also serious concerns regarding their safety [246,247].…”