Effects of adsorbed O2, H2, CO2 and H2O on the optical properites of pure and polymer encapsulated single walled carbon nanotubes

Abstract

We have measured the optical absorption spectra of single wall carbon nanotubes (SWCNTs) and SWCNT-polymer matrix samples at several temperatures and pressures. An in-situ cell was designed that allowed for heating of samples to 400 ^oC in vacuo (10-3 torr) was employed. Gases of interest were then introduced without re-exposure to atmosphere. The shifts in the magnitude and energy of the electronic transitions for both raw and pure SWCNT soots will be discussed. In the case of SWCNT-Polymer composites the thin films of homogenous solutions were spray-coated onto a quartz plate. The ability of the various polymers to coordinate to he nanotube helical structure appeared to have a direct affect on the SWCNT optical absorption spectra. The effect of both hydrophobic and hydrophilic polymers on the electronic transition of the SWCNTs will be presented.