Carbon nanotubes as a chemical sensor

G. U. Sumanasekera, B. K. Pradhan, Kofi W. Adu, R. E. Romero, P. C. Eklund

Research output: Contribution to journalConference article

2 Scopus citations

Abstract

A systematic study of the changes in the thermoelectric power (TEP) and four-probe resistance of vacuum-degassed thin films of nanotube bundles induced by the adsorption of polar alcohols and water six-membered ring molecules was presented. A strong effect on both the TEP, represented by S, and resistivity was found for methanol, ethanol, isopropanol, and butanol. For these four compounds, the TEP increased exponentially with time from the degassed value S0 ∼ -2.7 μV/K to a higher plateau after ∼ 1 hr. For methanol and ethanol, S was even driven positive, saturating at Smax ∼ +1.1 and +0.1 μV/K, respectively. Exposure to larger alcohol molecules, i.e., isopropanol and butanol, led to smaller changes in S and saturation at Smax ∼ -0.5 and -1.0 μV/K, respectively. Exposure to water vapor induced virtually no change in the TEP. S exhibited a linear relationship with ΔR/R0, consistent with the creation of a new impurity scattering channel via physisorption.

Original languageEnglish (US)
Pages (from-to)885-886
Number of pages2
JournalACS Division of Fuel Chemistry, Preprints
Volume49
Issue number2
StatePublished - Sep 1 2004

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All Science Journal Classification (ASJC) codes

  • Energy(all)

Cite this

Sumanasekera, G. U., Pradhan, B. K., Adu, K. W., Romero, R. E., & Eklund, P. C. (2004). Carbon nanotubes as a chemical sensor. ACS Division of Fuel Chemistry, Preprints, 49(2), 885-886.