An Electrokinetic Study of the Platinum-Potassium Iodide Solution Interface

摘要

The linear phenomenological laws as applied to electrokinetic effects are used to (1) show that problems arising from surface conductance may be avoided; (2) show that ac bridge measurements of the conductance of an electrokinetic system may lead to incorrect results; (3) develop characteristic curves for electrokinetic energy converters. It is shown that one of the linear equations is valid for the platinum-potassium iodide system. A general equation for the zeta potential-streaming current relation valid for porous media is developed. Evidence is adduced for the assignment of a Freundlich isotherm to the Gouy-Chapman surface charge at the platinum-potassium iodide solution interface whereas previous work indicates that the adsorption of iodide follows a Temkin isotherm. For a particular model the surface charge is related to surface dipole moment. A method of determining the isotherm for zeta potential determining species is proposed. (Author)