QUASI-EQUILIBRIUM POLARIZATION OF THE STERN LAYER AND LOW-FREQUENCY DIELECTRIC-DISPERSION

The formulas of the theory of concentration polarization in a double l ayer and low-frequency dielectric dispersion (LFDD) were generalized b y considering the concentration polarization in the dense part of the double layer (the Stern layer), under the condition of free ion exchan ge between the diffuse layer and the Stern layer. This mechanism of do uble layer polarization is distinguished by the dependence of the LFDD characteristic frequency on the particle size and on the effective di ffusion coefficient of the electrolyte and by a rather weak dependence on all other parameters of the system (for example, on the electrolyt e concentration). In contrast to similar studies by Lyklema and cowork ers, this generalization was obtained for an arbitrary ratio between t he Stern and the electrokinetic potentials, and considers the differen ce between the diffusion coefficients of the cations and anions. Becau se of the more general nature of the resulting formulas, they signific antly extend the possibility of interpreting the results of complex in vestigations, including LFDD and electrophoretic measurements.