Convective Contribution to Total Conductivity in Fixed‐Charge Ionic Systems

Abstract

A theory is presented for the contribution of convective (electro‐osmotic) flow to the total electric current in fixed‐charge ionic systems. Although the approximations used are severe, no assumption is made as to the geometrical structure of the system; in particular, the existence of capillary pores is not assumed. The result shows that convective flow contributes to the retardation effect of the fixed charges on the mobility of the counterions; moreover, the contribution is such as to suggest the possibility of measuring, in isolation from other factors, the dependence of the counterion self‐diffusion coefficient on interactions with the fixed charges.