Determination of the Exchange Current Density from Polarization Resistance

Determination of the Exchange Current Density from Polarization Resistance 

Elimination of diffusion overvoltage becomes readily available when the electrochemical system can be treated as linear. This is true in the neighborhood of the equilibrium potential where the overvoltage is sufficiently low. Let us consider 

in case of processes being analyzed, the value R is determined by Iq and the parameters of diffusion mass transport. If processes are fully reversible, the terms with the exchange current densities can be eliminated from Eqs. (5.35) or (5.36). In case of the irreversible process, on the contrary, members with limiting current densities may not be written. 

When studying polarization resistance of complex systems, kinetic equations must be rearranged accordingly. Here, we shall omit mathematical details, which were published earlier [21]. In case of the (Eq. (5.2)) mechanism, the following equation is obtained  

It should be noted that the latter two equations are obtained on condition that 13] If it does not take place, N is to be treated as the average number of coordinated ligands, but linear dependence between and 1/s/q remains. In case of consecutive transfer of two electrons, a similar equation is obtained  

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