Electric Double-Layer at Interface of Electrode and Electrolyte Solution

1 Electric Double-Layer at Interface of Electrode and Electrolyte Solution 

This scattered layer plus the electrode positive charge array is called the diffuse double-layer or diffuse layer. In the literature, this diffuse layer is also called the Gouy point charge layer or model or the Gouy-Chapman model. We will use the diffuse layer term in this chapter. The thickness of the diffuse layer is dependent on the temperature, the concentration of the electrolyte, the charge number carried by the ion, and the dielectric constant of the electrolyte solution. 

Positive charge Negative charge Solvent molecule 

In electrochemistry, the potential drop across the double-layer is described by the potential difference (A( )J H/s) between the irmer potential at a point in the metal electrode (( )ai) and the irmer potential at the end point of the diffuse layer in electrolyte solution (( ) (A( )jh/ = ( )m) - ( ) - This is called the absolute potential difference. The other expression of the potential drop is 

This outer potential difference is also called the Volta potential (also Volta potential difference, contact potential difference, or outer potential difference). It represents the potential difference between one point close to the electrode outer surface and the end point of the diffuse layer in the solution. The relationship between the outer and inner potentials can be expressed as  

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