Mechanism of enhanced sensitivity of linear poly(ethylenimine)-carbon black composite detectors to carboxylic acid vapors

Eric S. Tillman, Nathan S. Lewis

Research output: Contribution to journalArticle

33 Citations (Scopus)


Enhanced sensitivity towards volatile carboxylic acid vapors is obtained when the basic, amine-containing polymer, linear poly(ethylenimine), l-PEI, is used as the insulating component in a carbon black-polymer composite vapor detector. Specifically, at a partial pressure of analyte corresponding to 1% of its vapor pressure at room temperature, the signal-to-noise ratio for detection of acetic acid is 103 times larger than that for non-acidic organic vapors. Measurements of the mass uptake, thickness change, and electrical conductivity of such composites have been performed to elucidate the mechanism of this sensitivity enhancement towards volatile carboxylic acid vapors. These data have allowed quantification of the relative contributions of electrical percolation effects, increases in analyte sorption, and charge-induced swelling effects in determining the response characteristics of l-PEI composites.

Original languageEnglish
Pages (from-to)329-342
Number of pages14
JournalSensors and Actuators, B: Chemical
Issue number1-2
Publication statusPublished - Nov 15 2003



  • Amine-containing
  • Analyte
  • Percolation effects

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Instrumentation
  • Condensed Matter Physics
  • Surfaces, Coatings and Films
  • Metals and Alloys
  • Electrical and Electronic Engineering
  • Materials Chemistry

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