Enhancing the sensitivity of ionic liquid sensors for methane detection with polyaniline template

Xiaoxia Jin, Lei Yu, Xiangqun Zeng

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


Flammable gas sensors are essential in occupational health and safety to prevent fire or explosion in gas facilities and underground mining. Our early study demonstrated that ionic liquid (IL)/quartz crystal microbalance (QCM) gas sensors and sensor arrays were excellent for the detection of various organic vapors at both room temperature and elevated temperatures. In this paper, we developed a general method that significantly enhanced the sensitivity of the IL/QCM sensors for flammable gases detection by immobilizing IL on a conductive polymer polyaniline (PAn) template. Studies were performed to optimize the PAn oxidation states, thickness, and IL concentrations. Results showed that the sensitivity increased with increasing the PAn film thickness and the amount of IL immobilized within the PAn film. The sensitivity depended also on the oxidation state and doping state of PAn. With doped and partially oxidized PAn (emeraldine salt) the IL/QCM sensor showed the best performance. The current detection limit for methane was as low as about 115 ppm at room temperature. The sensitivity also depended on the structure of the IL used. Among the four ILs tested, two of them showed excellent sensitivities after being immobilized in the PAn film.

Original languageEnglish (US)
Pages (from-to)526-532
Number of pages7
JournalSensors and Actuators, B: Chemical
Issue number2
StatePublished - Aug 12 2008
Externally publishedYes

All Science Journal Classification (ASJC) codes

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


Dive into the research topics of 'Enhancing the sensitivity of ionic liquid sensors for methane detection with polyaniline template'. Together they form a unique fingerprint.

Cite this