Abstract
Explicit formulae for estimating the thicknesses of distribution forms of the potential, field and charge density of a planar electric double layer at high Zeta potential are presented.According to the exact solution of a planar electric double layer adaptable to arbitrary Zeta potential, reported by Verway and Nissen [Phil. Mag. 28 (1939) 435], the distribution forms of the potential, field and charge density are mathematically complicated in contrast to the Debye-Hückel theory that is valid for low Zeta potential, where these distribution forms are purely exponential. Asymptotic properties of the exact solution at high Zeta potential reveal that the thicknesses defined by the distances between the flat interface and the positions at which 1/e of the peak values of the potential, field and charge density are located, obey explicit asymptotic formulae.
