Acid-base properties of the surface of oxide materials

The system of equations corresponding to 4pK model of acid-base surface properties of oxide materials is composed and solved. It is shown that with decreasing of concentration of supporting electrolyte the point of zero charge of the protons of the surface is shifted toward lower pH values in case of specific adsorption of cations and toward higher pH in case of specific adsorption of anions. Substantiation of pK spectroscopy method is given. Basing on the data obtained pKspectrum is constructed corresponding to this model, it consists of two bands, which position depends on the concentration of background electrolyte.