The Dynamics of Electron Transfer Kinetics and Thermodynamics

The rate of electron transfer at an electrode-solution interface for the direct reduction of an oxidized species (ox) to its reduced state (red) [e.g., Cuu(bpy)2+ Cu (bpy)2+] 

The flux of ox that is reduced at the electrode (vL) has the dimensions of moles per unit area (cm2) per second, and 

In turn, combination of these equations gives expressions for the flux of ox reduction (vc) and cathodic current density (jc) for a potential difference AE  

The expressions for the reverse anodic process (oxidation) of Eq. (1.48) (red A. ox + ne ) follow from similar arguments  

When the cathodic current density (jc) is equal to the anodic current density (y J, the net current flow across the electrode-solution interface is zero and the net flux of ox and red is zero. For this unique condition (zero net current) the current densities represent the equilibrium exchange current density (j0)  

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