Dielectric behavior of electochemically prepared polypyrrole films

Summary form only given. Special interest has grown in the recent years for the search of novel polymeric conductors for their use in the solar cells, Schottky junctions, light weight batteries, EMI shielding and molecular electronics. The variation of electrical conductivity from insulator to metal range offers many exciting applications. However their chemical stability, strength and plasticity behavior are yet to be fully understood. Dielectric properties offer a very powerful tool to study some of these aspects and related features. In the present investigation, we have performed the dielectric measurements on polypyrrole (PPY) films in the temperature range 77 - 250K and in the frequency range 100 Hz - I MHz. The observed data were analysed using Cole and Cole expression. The derived dielectric loss peaks show a decrease in the loss maxima with increasing frequencies having a wide distribution of relaxation times. These observed loss peaks have been associated with the movement of the polarons.