Impedance of Faradaic reactions

An important conclusion from the paper by Brug et al. [1984] is that involvement of a CPE at solid electrodes used for studies of the impedance of Faradaic reactions can severely influence the frequency dispersion of interfacial admittance, leading to large errors in the determined Faradaic rate parameters. However, those authors note that it is feasible to account for the CPE effect correctly and to check the results of impedance analysis with respect to their internal consistency. The latter can be checked by a Kramers-Kronig analysis (cf. Lasia [1999]) which requires, however, detailed frequency-response data. Their approach was supported by experimental impedance studies on proton reduction at single and polycrystalline Au electrodes and on reduction of tris-oxalato-Fe(lII) (Brug et al. [1984]). 

D. A. Harrington and B. E. Conway [1987] ac Impedance of Faradaic Reactions Involving Electrosorbed Intermediates—... 

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