Synthesis, characterization and electrical properties of polyaniline/BaTiO3 composites

Conducting polyaniline/BaTiO3 (PANI/BT) composites have been synthesized by 'in situ deposition technique by placing fine graded BaTiO3 in polymerization mixture of aniline. The composites are characterized using various techniques such as SEM, XRD and IR spectroscopy. The electrical properties such dc conductivity and ac conductivity are studied by sandwitching the pellets of these composites between the silver electrodes. It is observed that in both the cases the values of conductivities increases up to 30 weight % of BaTiO3 in polyaniline and decreases thereafter. Initial increment in conductivity is due to extended chain length of polyaniline where polarons possess sufficient energy to hop between favorable sites. Beyond 30 weight % of BaTiO3 in polyaniline, the blocking of charge carriers takes place reducing the conductivity values. The polyaniline/ BaTiO3 composites are poled by applying constant voltage for a fixed time to study their electrical hysteresis characteristics. It is observed that the area under the curve depends on the content of BaTiO3 in polyaniline.