Dielectrical properties of PANI/TiO₂ nanocomposites

Conducting polyaniline/titanium dioxide (PANI/TiO₂) composites have been succesfully synthesized by insitu polymerization technique. The PANI/TiO₂ nanocomposites of different compositions were prepared by varying weight percentage of TiO₂ nanoparticles such as 10 wt%, 20 wt%, 30 wt%, 40 wt% and 50 wt% into the fixed amount of the aniline monomer. The prepared powder samples were characterized by X-ray diffractometer (XRD) and Scanning electron microscope (SEM). The intensity of diffraction peaks for PANI/TiO₂ composites is lower than that for TiO₂. SEM pictures show that the nanocomposite were prepared in the form of long PANi chains decorated with TiO₂ nanoparticles. The dielectric properties and AC conductivity were studied in the frequency range1K Hz–10M Hz. At higher frequencies, the composites exhibit almost zero dielectric loss and maximum value of σ_ac is found for a concentration of 20 wt% TiO₂ in polyaniline. The interface between polyaniline and TiO₂ plays an important role in yielding a large dielectric constant in nanocomposites.