POST-PRODUCTION SEPARATION AND FUNCTIONALIZATION OF SINGLE-WALLED CARBON NANOTUBES

ABSTRACT Single-walled carbon nanotubes (SWNTs) are considered to have many potential applications due to their unique structural, physical, chemical and electronic properties. Because the rigid structure of carbon nanotube determines its toughness in dissolution, the processing capability of carbon nanotube is strongly limited. My carbon nanotube functionalization research was mainly focused on developing innovative methods to functionalize nanotubes with various polymers and large aromatic molecules to make them soluble to study their interesting properties and applications. In this dissertation, different methods for the functionalization and solubilization of carbon nanotubes are described. The co-existence of metallic and semiconducting carbon nanotubes has often been a bottleneck in many applications including future nanoelectronic devices. Therefore, the separation of SWNTs based on electronic structure and diameter is very important. The separation of SWNTs based on electronic structure and diameter using non-covalent functionalization methods was performed. The separated nanotube samples were characterized using optical spectroscopy, Raman spectroscopy, thermal gravimetric analysis and electron microscopy and the results revealed that the separation of nanotubes based on electronic structure and diameter was achieved successfully. In addition, the electronic band gap transitions related to SWNTs (especially semiconducting band gap transitions) were found to be very sensitive to surrounding chemical species. The doping of these electronic transitions by larger aromatic species is also discussed