Development of gas sensor from conducting polymer composite containing poly (3,4-ethylenedioxythiophene)

Abstract

This research aims to study film processing of the conducting polymer composites containing poly(3,4-ethylenedioxythiophene) (PEDOT) using solid state polymerization of 2,5-dibromo-3,4-ethylenedioxythiophene (DBEDOT) in the polymer matrix on the interdigitated electrode (IDE) for gas sensing applications. The most appropriate condition for preparing DBEDOT-containing composite film was to spin casting the mixed solution of polybutadiene (PB) and DBEDOT dissolved in toluene at 1:10 (w/w) of PB:DBEDOT on IDE with a spin speed of 1500 rpm for 60 sec, and induced SSP of DBEDOT to conductive PEDOT by heating the PB/DBEDOT composite film at 60 oC for 8 h. The PB/PEDOT composite film having a resistance of 103 ohm was chosen for testing against a number of volatile chemicals. The resistivity of the PB/PEDOT composite film was systematically changed with the polarity of the chemical. The PEDOT-based sensor gave good responses to polar solvents such as methanol, ethanol, and water. The repeatability and sensitivity of the developed sensor were also determined.