Impedance spectroscopy and transport properties of polymer-based flexible nanocomposites

The flexible nanocomposites of bismuth ferrite and polyvinylidene fluoride were prepared by the solution casting method. The X-ray diffraction technique confirms the presence of both the inorganic filler (bismuth ferrite) and polymer phases. Atomic force microscopy study shows the increasing values of root mean square (RMS) roughness in the nanocomposites. The modulus and impedance spectroscopy were performed to get insight contribution of grains, grain boundaries, and interfaces on the electrical properties. From the Nyquist plot analysis, grains effect is dominant over the grain boundaries and non-Debye type relaxation behavior is observed for the nanocomposites. Correlated barrier hopping (CBH) model is the most suitable model to explain the transport properties of the charge carriers. The hopping distance increases from 8.11 angstrom to 27.25 angstrom with increasing the content of inorganic fillers in the nanocomposites. The presence of the different conduction processes at various temperature regions is explained by the Arrhenius plot analysis.