An Approximate Expression of Double Layer Interaction Between Two Parallel Similar Plates with High Constant Surface Potential in Asymmetric Electrolytes

Abstract

Using the extended Langmuir's method, we derived the relation of surface potential, potential midway, and the plate distance for asymmetric electrolytes in the case of high constant surface potential. Thus, we obtained an approximate expression of the interaction force and energy between two similar plates for asymmetric electrolytes at constant surface potential. It is found that this approximation works quite well for small plate separations for asymmetric electrolytes at high surface potentials.

Keywords:

• Poisson–Boltzmann equation
• Double layer interaction
• Asymmetrical electrolyte
• Langmuir's method

Acknowledgment

We are grateful to the National Science Foundation of China (NSFC) for financial support no. 20273028.