AC conduction in nanocomposites of polypyrrole

The electrical conductivity of polypyrrole based nanocomposite has been reported in the frequency range of 1 kHz to 1 MHz and temperatures in the range 20-320 degreesC. In the low temperature region the measured ac conductivity is nearly independent of temperature but strongly frequency dependent and can be described by the relation sigma(omega) = Aomega(s). The high temperature region shows weak frequency dependence at low frequencies but is strongly frequency dependent at higher frequencies. The observed behaviour has been examined in the light of existing theories used to characterize amorphous solids. (C) 2003 Published by Elsevier B.V.