Features of Electrosorption and Factors Affecting Them

The simplest of the adsorption processes on electrodes is the monolayer reversible adsorption of a neutral organic compound on an energeticMy homogeneous electrode surface, like the surface of a Hg electrode. The typical features of this process when the solute molecules do -not reorientate on the electrode are the following 

The maximum in adsorption occurs at a constant value of the applied potential E, the potential drop across the adsorbed monolayer A(J , and the electrode charge density This property leads to the appearance of a common intersection point in the plots of vs. E at constant solute mole fractions X in the electrolyte solution. 

The adsorption is accompanied by a decrease in the differential capacity C in the region of E x, the potential of maximum in adsorption. At potentials more positive or more negative than Emwc the organic adsorbate is desorbed giving rise to typical adsorption-desorption peaks. 

the subscript S denotes a solvent molecule, A a solute 

The standard Gibbs energy of adsorption, AGajx, depends quadratically upon the electrical variable X (= , A(j) or a ). 

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