CO sensor based on polypyrrole functionalized with iron porphyrin

Santhosh Paul, Francis Amalraj, S. Radhakrishnan

Research output: Contribution to journalArticlepeer-review

71 Scopus citations


Polypyrrole (PPy) was chemically functionalized with 5,10,15,20-tetraphenyl-21H,23H-porphyrin iron(III) chloride (FeTPPCl) with special interest on noxious carbon monoxide (CO) gas in ppm level. Controlled functionalization of PPy was achieved with incorporation of various concentrations of porphyrin. The resulted semiconducting material was well characterized by different techniques such as UV-vis spectroscopy, FTIR, GFAAS, XRD, and EDAX. The functionalized polypyrrole material on interdigitated electrode was experienced an immediate increase in resistance when exposed to carbon monoxide gas at very low concentration. The CO gas interacted very fast with the FeTPPCl functionalized PPy at room temperature (RT) and then slowly saturated. The response of these materials was not unidirectional, but reverses to the original resistance level when CO was removed from the test chamber. The highest response factor (ΔR/R0 × 100) and lowest response time (t50) obtained are 12 and 169 s, respectively. An optimum level of doping (1 mol% of FeTPPCl) was established for the highest sensitivity and the detection level is as low as 100 ppm.

Original languageEnglish
Pages (from-to)1019-1023
Number of pages5
JournalSynthetic Metals
Issue number11
StatePublished - Jun 2009
Externally publishedYes


  • Carbon monoxide
  • Chemical sensor
  • Fe(III) porphyrin
  • Polypyrrole


Dive into the research topics of 'CO sensor based on polypyrrole functionalized with iron porphyrin'. Together they form a unique fingerprint.

Cite this