Title: Surfaces of carbon nanotubes as revealed by thermogravimetric and solvent extraction techniques

Abstract

Perhaps the greatest challenge in the real-world application of carbon nanotubes is a lack of practical knowledge about the chemical nature of their surfaces. Compounding the problem is that many commercial nanotube manufacturers produce admixtures of tube types. While it is possible in some cases to separate and isolate the types, such processes are limited in terms of species that can be isolated and often require specialized equipment. In this study I present demonstrate how deconvolution of thermogravimetric mass loss curves reveals the number of carbon species present, and the validity of the deconvolution is confirmed through both statistical tests and application of accepted combustion kinetic models (e. g. Fraser Suzuki). The resulting distribution functions obtained for the combustion activation energies are discussed, especially with respect to surface chemical homogeneity and carbon nanotube network morphology. Comparisons between raw samples and those that have had surface contaminants removed using a Soxhlet technique are also given. These contaminants are mainly polyaromatic hydrocarbons, identified here using GC/MS and UV-Vis spectrometry and their implications for nanotube synthesis are presented.