Applications of Thermogravimetric Analysis in Quality Control of Single-Walled Carbon Nanotubes
Elisabeth Mansfield, Aparna Kar, Stephanie A. Hooker
Carbon nanotube exhibit a range of chemistries, including mixtures of different nanotube diameters, lengths and chiralities, coupled with various concentrations of metallic and non-nanotube carbon impurities. The performance of a given material for a specific application is highly dependent on the chemistry, which is dictated in large part by the manufacturing process. Here, thermogravimetric analysis is reported as a bulk characterization method for determining nanotube quality after manufacturing. The application of thermogravimetric analysis for determining basic nanotube chemistry is described (e.g., carbon-to-metal content, homogeneity). In addition, extension of the method to more sensitive analysis of specific nanotube properties (i.e., length and diameter) is illustrated. Results indicate that thermogravimetric analysis is sufficiently sensitive to enable quality control at both the macro- (carbon-to-metal ratio) and nano- (single-walled to multi-walled) scales and can detect subtle modifications in manufacturing processes.