Highly conductive single-walled carbon nanotube thin film preparation by direct alignment on substrates from water dispersions

Seyla Azoz, Annemarie L. Exarhos, Analisse Marquez, Leanne M. Gilbertson, Siamak Nejati, Judy J. Cha, Julie B. Zimmerman, James M. Kikkawa, Lisa D. Pfefferle

Research output: Contribution to journalArticle

14 Scopus citations

Abstract

A safe, scalable method for producing highly conductive aligned films of single-walled carbon nanotubes (SWNTs) from water suspensions is presented. While microfluidic assembly of SWNTs has received significant attention, achieving desirable SWNT dispersion and morphology in fluids without an insulating surfactant or toxic superacid is challenging. We present a method that uniquely produces a noncorrosive ink that can be directly applied to a device in situ, which is different from previous fabrication techniques. Functionalized SWNTs (f-SWNTs) are dispersed in an aqueous urea solution to leverage binding between the amine group of urea and the carboxylic acid group of f-SWNTs and obtain urea-SWNT. Compared with SWNTs dispersed using conventional methods (e.g., superacid and surfactants), the dispersed urea-SWNT aggregates have a higher aspect ratio with a rodlike morphology as measured by light scattering. The Mayer rod technique is used to prepare urea-SWNT, highly aligned films (two-dimensional nematic order parameter of 0.6, 5 μm spot size, via polarized Raman) with resistance values as low as 15-1700 ω/sq in a transmittance range of 2-80% at 550 nm. These values compete with the best literature values for conductivity of SWNT-enabled thin films. The findings offer promising opportunities for industrial applications relying on highly conductive thin SWNT films.

Original languageEnglish (US)
Pages (from-to)1155-1163
Number of pages9
JournalLangmuir
Volume31
Issue number3
DOIs
StatePublished - Jan 27 2015

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ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Spectroscopy
  • Electrochemistry

Cite this

Azoz, S., Exarhos, A. L., Marquez, A., Gilbertson, L. M., Nejati, S., Cha, J. J., Zimmerman, J. B., Kikkawa, J. M., & Pfefferle, L. D. (2015). Highly conductive single-walled carbon nanotube thin film preparation by direct alignment on substrates from water dispersions. Langmuir, 31(3), 1155-1163. https://doi.org/10.1021/la503919u