Impedance Spectroscopy on Polymeric Nanofibers

Electrochemical impedance spectroscopy is very useful technique to understand the microstructure and related further electrical properties of conjugated pol5miers. Optimization of properties of films is the key for a wide range of applications.  

Aconjugatedpol5miermodifiedelectrode(CPME)canbeonsidered as a heterogeneous system consisting of polymer film between the metal electrode and electrolyte. Two different interfaces behave as transition regions, and the properties are different from those of the bulk properties of the electrode, solution and the pol nner film. 

The impedance of a modified electrode depends on the impedance of each of the bulk phases and on interfacial properties as well. The equivalent circuit model (ECM) is used to elucidate the contribution of different charge transfer or transport processes to the overall impedance of electrodes. The equivalent circuit modeling concern finding equivalent electrical elements best representing physical processes within a range of frequencies by assuming each element 

To model electrochemical behavior in connection with equivalent circuit composed of a number of single and/or sub-circuit elements. The capacitors and resistors can be obtained from the impedance spectrum (Fig. 6.1). 

The complex impedance data involves the interplay of three variables, the imaginary component of the impedance, the real component of the impedance, Zreai, and the phase angle, p. To represent these variables as a function of frequency most common types of representation for impedance data are, the Nyquist and the Bode representations. Nevertheless, these have become the most widely used graphical representations of impedance data. 

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