Optimizing processes of dispersant concentration and post-treatments for fabricating single-walled carbon nanotube transparent conducting films

- SWCNT TCFs were prepared by different proportions of CNTs/SDBS solution that the ratio of CNTs/SDBS 1:5 gave the lowest sheet resistance both for pristine and nitric acid-treated films.
- The mechanism SDBS dispersing CNTs and TCFs treated with nitric acid were investigate according to SEM, Raman and XPS.
- Finally TCFs fabricated with CNTs/SDBS 1:5 solutions were further treated by a simple method that immersion with SOCl2 to achieve lower sheet resistance, we also explored the effect of SOCl2 on TCFs with XPS and Raman.

This study evaluated the effect of sodium dodecyl benzene sulfonate (SDBS) as dispersant for the dispersion of purified single-walled carbon nanotubes (SWCNTs) in water in terms of dispersibility dependence on electrical conductivity of SWCNT transparent conducting film (TCF) performance. SWCNT TCFs were prepared by different proportions of CNTs/SDBS solution to find out the optimum SDBS concentration according to the film resistance of pristine and after post-treatment by nitric acid. TCFs fabricated with the aqueous solution by the ratio of CNTs/SDBS 1:5 gave the lowest sheet resistance and the highest transmittance. The TCFs were then further treated with thionyl chloride to improve their conductivity. Low sheet resistance (86 Ω/□, 80%T) was achieved. The dispersion condition of CNTs/SDBS aqueous solution was characterized by field-emission scanning electron microscopy, while the X-ray photoelectron spectroscopy and Raman spectroscopy confirmed the dispersion and doping mechanism treated with nitric acid and thionyl chloride.