Ion adsorption equilibrium

The process in which a hydrated ion is dehydrated to form an adsorbed ion on an electrode interface, and its reverse process, are ion transfer processes across the compact layer on the electrode interface. As an example, we consider proton adsorption (cathodic proton transfer) and proton desorption (anodic proton transfer) at metallic electrodes represented by Eqn. 9-59  

In adsorptioDr-desorption equilibrium, the adsorption coverage of protons, 6h-(= is derived from the Nemst equation of electrochemical equilibria to 

As the proton coverage increases, the interaction among adsorbed protons increases leading to Temkin s adsorption isotherm [Temkin, 1947], and Eqn. 9-61 is obtained  

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