Low-Frequency Dependence of Conductivity and Dielectric Properties of Polyaniline/ZnFe2O4 Nanocomposites

Conducting polyaniline/ZnFe2O4 nanocomposites are synthesized by using a simple and inexpensive one-step in-situ polymerization method in the presence of ZnFe2O4 nanoparticles. The structural, morphological and electrical properties of the samples are characterized by x-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy. These results reveal the formation of polyaniline/ZnFe2O4 nanocomposites. The morphology of these samples is studied by scanning electron microscopy. Further, the ac conductivity (sigma(ac)) of these composites is investigated in the frequency range of 1 kHz-10 MHz. The presence of polarons and bipolarons are responsible for the frequency dependence of ac conductivity in these nanocomposites. The ac conductivity is found to be constant up to 1 MHz and thereafter it increases steeply. The ac conductivity of 0.695 S.cm(-1) at room temperature is observed as the maxima for the polyaniline with 40wt% of the ZnFe2O4 nanocomposite.