Electrode Coated with an Inert Porous Layer

1 Electrode Coated with an Inert Porous Layer 

Surface films commonly form in electrochemical studies, and these films can influence the impedance response. The electrode coated with an inert porous layer may be considered to be an extension of the case described in Section 9.2.2 in which the film is thicker and the fractional surface coverage approaches unity. 

The electrolyte resistance Re is added in series with the previous impedance. If the electrochemical reaction is mass-trai3sport limited, the previous equivalent circuit is still valid, but the Faradaic impedance includes a diffusion impedance as described in Chapter 11. 

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