Influence of high temperature treatments on single-walled carbon nanotubes structure, morphology and surface properties

Single-walled carbon nanotubes produced by the MER Corporation have been treated in an argon atmosphere at temperatures between 1400 and 2400 degreesC. The modifications resulting from the heat treatment have been followed by adsorption volumetry and TEM measurements, 1600 degreesC appears as a turning point for the high temperature treatments. Heating nanotubes up to 1600 degreesC essentially results in the removal of metal particles. At higher temperatures the changes in morphology are predominant, and single-walled nanotubes packed in bundles are transformed into multi-walled nanotubes. (C) 2001 Elsevier Science Ltd. All rights reserved.