Electrical and humidity sensing properties of polyaniline/WO 3 composites

Abstract

Conducting polyaniline/tungsten oxide (WO 3) composites have been synthesized by 'in situ' deposition technique by placing fine graded WO 3 in polymerization mixture of aniline. This is a single step polymerization process for the direct synthesis of emeraldine salt phase of the polymer. The results were also well supported by FTIR spectral analysis, scanning electron microscope (SEM), XRD and conductivity measurements. High temperature conductivity measurements show thermal activated behavior. The change in resistance with respect to percent relative humidity (RH) is observed. The composites in the pellet form exhibit almost linear behavior within a chosen range of humidity (ranging between 10 and 95% RH). © 2005 Elsevier B.V. All rights reserved.