Diffuse layer charge

The potential difference across the mobile part of the diffuse-charge layer is frequently called the zeta potential, = E(0) — E(oo). Its value depends on the composition of the electrolytic solution as well as on the nature of the particle-hquid interface. 

For many particles, the diffuse-charge layer can be characterized adequately by the value of the zeta potential. For a spherical particle of radius / o which is large compared with the thickness of the diffuse-charge layer, an electric field uniform at a distance from the particle will produce a tangential electric field which varies with position on the particle. Laplace s equation [Eq. (22-22)] governs the distribution... 

An adsorbed layer of water molecules at the interface separates hydrated ions from the solid surface. The interfacial electric double layer can be represented by a condenser model comprising three distinct layers a diffuse charge layer in the ionic solution, a compact layer of adsorbed water molecules, and a diffuse charge layer in the solid as shown in Fig. 5-8. The interfacial excess charge on the... 

Diffuse charge layer (Space charge layer)... 

Fig. 5-8. Diffuse charge layer on the solution side of metal electrode M = electrode metal S = aqueous solution HL = compact layer (Helmholtz layer) DL = diffuse charge layer x distance from the outer Helmholtz plane (OHP).

Figure 1 The electrical double layer and the potential distribution at the surface 1, fixed surface charges 2, Stern layer of "fixed" charges 3, Gouy or diffuse charge layer 4, counterions 5, Helmholtz plane 6, plane of shear 7, potential distribution in the electrical double layer.

It will be seen that this case differs from the foregoing one in that we are now dealing wj,th a double layer consisting of two diffuse charge layers in each of these layers the electrical potential function is given by equations completely analogous... 

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