The effect of the PANI-free volume on impedance response

The influence of the PANI structure on the conductive mechanism and on the electrical equivalent circuit analysis

“…EEC1 was used, because it was recently demonstrated that EEC1 has the same physical behavior as PANI of different thicknesses [31]. In order to obtain PANI impedance data that contain changes in PANI when the number of synthesis cycles is gradually increased, parameters (Table 1) were predetermined.…”

“…Generally, it is well-known that the exchanges of the counter-ions in PANI and at the PANI/electrolyte interface are the two main processes responsible for impedance behavior [18,40]. Recently, it was reported [31] that the structure of PANI has an important influence on the impendence response. Therefore, the influence of PANI structural changes on the impedance behavior and on the EIS analysis is debated here.…”

“…The two explained processes related to PANI during the EIS response can be represented by two RC circuits in series (1). It is useful to keep in mind that the correlations between PANI properties and transfer function (1) were established in the previously reported paper [31]; (1) will result in PANI experimental data of known ''electrical" origin that will be used to approve or disapprove the application of proposed EEC in EIS analysis. …”

“…An increment in the PANI-free volume was reported when the thicker PANI was synthesized [26][27][28], which has an influence on the R ct2 value [5]. Also, the real surface area of the PANI/electrolyte interface (C dl ) is enlarged when the higher number of the synthesis cycles was used [31]. Therefore, if all EEC parameters have physical meaning, it can be concluded that the proposed EEC is justified for the impedance analysis and only then the proposed method will approve the application of EEC under the investigation.…”

“…The analysis of corrupted experimental impedance response can result in the different PANI ''electrical" origin and by the application of different EEC. Therefore, in this work the experimental impedance response of the different thickness PANI layers was calculated by previously investigated EEC [31] and by predetermined EEC parameters. The calculated experimental impedance response data serve the purpose of facilitating a better understanding of the proposed method application, thus widening the scope of this investigation.…”