In-plane impedancemetric ammonia sensing of solution-deposited, highly semiconductor-enriched single-wall carbon nanotube submonolayer network gas sensors

Hyun Pyo Hong, Joon Hyub Kim, Cheol Jin Lee, Nam Ki Min

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

We present the impedancemetric operation of ammonia gas sensors based on drop-deposited, 99% semiconductor-enriched single-walled carbon nanotube networks. Impedance spectroscopic data for these devices exhibit a complex impedance over a range of frequencies (0.5 Hz to 300 kHz) and are well fit with a proposed equivalent electrical circuit model. The effect of NH<inf>3</inf> on the high-frequency arc resistance is described by a linear law at all NH<inf>3</inf> concentrations, indicating the possibility of utilizing the impedance spectra as the main sensing signal. The impedancemetric operation mode demonstrates a sensitivity of 3.70%/ppm at 3.6-41.4 NH<inf>3</inf> concentration, which is equivalent to an improvement in sensitivity of 2.1 times compared to conventional direct current (dc) measurement. Furthermore, impedancemetric sensing is much less susceptible than conventional dc to noise problems in the very low frequency or dc due to ionic contamination or dissociated NH<inf>3</inf> molecules.

Original languageEnglish
Pages (from-to)27-32
Number of pages6
JournalSensors and Actuators, B: Chemical
Volume220
DOIs
Publication statusPublished - 2015 Jun 8

Keywords

  • Gas sensor
  • Impedance spectroscopy
  • Impedancemetric detection
  • Semiconductor-enriched SWCNT
  • Sensing mechanism

ASJC Scopus subject areas

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

Fingerprint Dive into the research topics of 'In-plane impedancemetric ammonia sensing of solution-deposited, highly semiconductor-enriched single-wall carbon nanotube submonolayer network gas sensors'. Together they form a unique fingerprint.

  • Cite this