Ion transfer at the interface between an aqueous solution in the presence of concentrated salts and an organic solution studied by polarography at the electrolyte solution dropping electrode

Abstract Voltammetry at the interface of two immiscible electrolyte solutions has been demonstrated as one of the best methods for the investigation of the dissolved states of rather hydrophobic ions (i z ) in an aqueous solution (W) or the transfer of i z from W to an organic solution, even in the presence of highly concentrated hydrophilic salts in W. Based on half-wave potentials and diffusion currents in the voltammograms (polarograms in the present case) observed with various kinds and/or concentrations of coexisting salts, the effects of the salts on the transfer energies of i z were obtained. Also, the dissolved states of i z in W in the presence of concentrated coexisting salts were evaluated, taking into account the dehydration of i z owing to the decrease in the water activity, the formation energy for a cavity to immerse i z into W, the dispersion force working on i z and the ion pair formation of i z with the coexisting counter ion.