Transient behaviors of interacting electrical double layers
Journal
Colloid and Polymer Science
Journal Volume
276
Journal Issue
3
Pages
213-218
Date Issued
1998
Author(s)
Kuo Y.-C.
Abstract
The unsteady-state potential and space charge distributions between two identical, planar parallel charged surfaces immersed in an c:b electrolyte solution are examined theoretically. The effects of the ratio of the diffusivities of counterions and coions, Dcon/Dco, the mean diffusivity (DconDco)1/2, and the separation distance between two surfaces, H, on the transient distributions of electrical potential and space charges are investigated. The result of numerical simulation reveals that the extent of a system to reach its new equilibrium state depends largely on the magnitude of a scaled time v(=Dt£e2). For a fixed H, the greater the value of v, the closer a system to its new equilibrium state. For constant H and v, the smaller the ratio (Dcon/Dco), the greater the deviation of a system from its new equilibrium state. In addition, the effect of Dcon on this deviation is greater than that of Dco.
Subjects
Electrical double layer
Electrical interactions
Non-equilibrium potential distribution
Poisson equation
Type
journal article