Authors : V. R. Bhonde
Page Nos : 217-218
Description :
Impedance analysis correlates the electrical properties to the microstructure of material. It is also useful to analyze the different contributions to the electrical properties. In the study of dielectric behavior of conducting polypyrrole, an attempt has been made to enlighten the electrical and micro-structural properties of polypyrrole of different weight percentage in relation with frequency and temperatures over the wide range. Cole-Cole plot of Zï‚¢ï€ and Zï‚¢ï‚¢ï€ of complex impedance of polypyrrole for different weight percentage in the frequency range 100 Hz to 200 KHz and at temperatures 313, 333,248, 373 and 398K is analyzed. It is found that the Cole-Cole plots are semicircles. As the semicircle does not coincide with the origin, shows that series resistance can be ascribed to the circuit. The ï€ Zï‚¢ï‚¢ï€ - Zï‚¢ï€ plot shows single semicircle indicating dispersion as mono-dispersive. For Debye type relaxation mechanism the centre of circle lies on Zï‚¢ï€ ï€¬ï€ axis. At the peak of Cole- Cole plot, the relaxation time ï´m is calculated. The relaxation time evaluated from Debye semicircle determines the activation energy for the dielectric. The values of bulk resistance RB and bulk capacitance CB has been calculated from Zï‚¢ï‚¢ï€ - Zï‚¢ plot.
Keywords Impedance analysis,conducting polypyrrole,Cole-Cole plot,activation energy
