Fractional Diffusion Equations and Equivalent Circuits Applied to Ionic Solutions

Abstract

We investigate dilute solutions of different salts (KClO3, K2SO4, and CdCl2H2O) dissolved in Milli-Q deionized water in the context of the fractional diffusion equations and equivalent circuits. The experimental results show that in the low frequency limit the behavior of the impedance is suitable described in terms of the boundary conditons which can be connected to constant phase elements (CPE). In addition, they also indicate that salts with similar characteristics, such as the ionic potential for the negative ion, present essentially the same frequency dependence of the impedance in the low frequency limit.