Charge Transport Through the Electroactive Film

Two types of model have been used to describe the charge transport through electroactive films continuous models, considering ionic transport in a compact film based on the Nernst-Planck equations, and porous models, whose transport is described by transmission line equivalent circuits. 

By definition, the fluxes of species i,Ji, are positive for outgoing species  

The global potential across the modified electrode, E (the metal electrode is supposed to be grounded), is the sum of three quantities  

Generally, the total faradaic electrochemical impedance, Zf ( ), is obtained by considering 

As a simplifying assumption, which will be used in the following, the charge transport mechanism, which occms in the bulk polymer during an oxidation/reduction reaction of the polymer in aqueous media, can be modelled by assmning that the transport of the species in the electrolyte is sufficiently fast and is not a limiting step. 

---