Semiconducting single walled carbon nanotubes (SWNTs) have long been known to exhibit chirality-dependent, tunable bandgaps with narrow absorption and emission line widths in the visible and infrared region of the spectrum, with center wavelength positions correlating roughly with nanotube diameter due to two-dimensional quantum confinement effects. The technique of amide gel based adsorption and desorption has afforded the ability to separate preparative quantities of semiconducting SWNT into single- and few-chirality samples. Determining the purity and stability of separation based on this method is of utmost importance in understanding and improving the efficiency and breadth of gel-based SWNT separation. This work focuses on the development of a model to fit semiconducting SWNT absorbance spectra with a series of Lorentzian lineshapes, coupled with a linear combination of exponential background components. The model incorporates contributions from high energy phonon sidebands, as well as low energy sidebands, shown to be present for each unique chirality. The presence and concentration of specific chiralities are confirmed using a multi-region cross fitting technique. In addition, the stability of colloidal suspension of few- and single-chirality samples over time and through ultracentrifugation is modeled using the Lamm equation.

Novel approach to modeling the absorption spectra and colloidal stability of few- and single-chirality single walled carbon nanotubes

249th National Meeting (2015)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.