TIME-DOMAIN RESPONSES OF CONSTANT PHASE ELECTRODES

Electrochemical Impedance Spectra of solid electrodes presenting const ant phase characteristics in the frequency domain are well recognized. Constant phase components are usually involved, at least formally, in most mathematical procedures used for resolving electrochemical imped ance spectra. This is not the case for time domain responses of the sa me electrodes. The consequences of constant phase behavior for time do main responses are presented in terms of hystereses, non-steady state and irreversibility concepts. Time domain pulse responses simulated wi th algorithms of fractional calculus exhibit E-I-t relations closely r elated to experimental data. Two particular cases of practical importa nce are analyzed in detail: electrochemical adsorption on fractal surf aces and the Stern method of linear polarization used for corrosion te sts.