LSV/CV modelling of electrochemical reactions with interfacial CPE behaviour, using the generalised Mittag–Leffler function

This article deals with the influence of interfacial CPE (constant phase element) behaviour on linear scan voltammograms (LSV) and cyclic voltammograms (CV). Theoretical investigation is carried out using the generalised Mittag–Leffler function which arises naturally in the solution of fractional order integral or differential equations. First, ohmic drop and CPE effects are analysed in the absence of electrochemical reaction through the closed-form expression of current vs. time. Next, the combined effects of ohmic drop, CPE and faradaic processes are modelled using the integral equation approach. Finally, the example of one-step electrochemical reaction, investigated under semi-infinite linear diffusion conditions, is dealt with for illustration of the calculation procedure.

► Modelling the dynamics of electrochemical systems with interfacial CPE behaviour. ► Combined effects of ohmic/CPE processes are modelled in closed form. ► Faradaic/ohmic/CPE processes are investigated by the integral equation approach. ► Application to linear scan voltammetry and cyclic voltammetry methods.