ISSN:
1057-9257
Keywords:
conducting polymers
;
sensors
;
polyaniline
;
conducting composites
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
A conducting polymer-based chemical sensor was fabricated by depositing a film containing polyaniline blended with polyethylene oxide and doped with copper chloride onto interdigitated electrodes in a surface cell configuration. It was found to be very sensitive to alcoholic vapours, especially methanol. Its characteristics such as response time (tr), recovery time (td), sensitivity factor (σmax/σ0), etc. have been studied with respect to film composition, chemical vapour dosage, etc. It was found that the sensitivity was maximum and tr minimum at a certain concentration of polyaniline in the film matrix. Although the response was quite fast (tr 〈 10 s), the recovery was slow and in many cases followed a two-step process. The two components in the recovery were clearly delineated in log-log plots, from which one could be associated with diffusion and the other with selective residual adsorption of the chemical vapour by the conducting polymer moieties. These results have been discussed in the light of the charge transport mechanism and the formation of interfacial barriers between polyaniline domains.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
