title: Dispersion of nitric acid-treated SWNTs in organic solvents and solvent mixtures.
abstract: The dispersion of pristine and nitric acid-treated single-wall carbon nanotubes (SWNTs) has been studied in organic solvents and solvent mixtures using optical absorption, as a function of settling time. The extinction coefficients of both the pristine and acid-treated tubes at 500-nm wavelength was measured to be 25.5 (mg/L)(-1) cm(-1) in various solvents. The dispersibility of nitric acid-treated tubes increased with the solvent's hydrogen-bonding ability and reached 27 mg/L in ethanol and 35 mg/L in water. Nitric acid-treated tubes could also be dispersed in butanol/toluene and xylene/ethanol mixtures, which are known to be poor solvents for the pristine SWNTs.
authors.affiliation: School of Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: Geon-Woong
authors.initials: GW
authors.lastname: Lee
authors.forename: Satish
authors.initials: S
authors.lastname: Kumar