Equilibrium differential capacitance and electrocapillary curves within the framework of a generalized model of the surface layer

Abstract

Equations that describe the equilibrium differential capacitance C and the interface tension of an electrode subjected to the adsorption of organic molecules under the conditions where this adsorption strictly follows a generalized model of the surface layer are derived. Using the developed programs, the dependences of C on the electrode potential φ are calculated at different concentrations of the organic substance. Based on these C vs. φ curves, a set of effective parameters is obtained. With these parameters, the capacitance curves can best be described by the model of two parallel capacitors combined with the Frumkin isotherm.