Diffusiophoresis of colloidal spheroids in symmetric electrolytes
Resource
Colloids and Surfaces A: Physicochemical and Engineering Aspects 92 (1-2): 51-65
Journal
Colloids and Surfaces A: Physicochemical and Engineering Aspects
Journal Issue
92
Pages
51-65
Date Issued
1994
Date
1994
Author(s)
Huang T.Y.
Abstract
An analytical study is presented of the diffusiophoresis of a non-conducting spheroid in a solution of symmetric electrolyte with a constant concentration gradient oriented arbitrarily with respect to the axis of revolution of the spheroid. The thickness of the electric double layer surrounding the spheroid is assumed to be small relative to the dimension of the particle, but the effect of the polarization of the mobile ions in the diffuse layer is incorporated. To solve the conservative equations governing the system, a slip velocity of fluid and normal fluxes of solute ions at the outer edge of the thin double layer which balance convection and diffusion of the solute ions along the particle surface are used as the boundary conditions for the fluid domain outside the diffuse layer. Explicit expressions for the diffusiophoretic and electrophoretic velocities of a spheroidal particle and the average particle velocities in an ensemble of identical, non-interacting spheroids with random orientation distribution are obtained. It is found that the diffusiophoretic and electrophoretic velocities of the particle decrease with the reduction of the maximum length of the particle in the direction of migration. © 1994.
SDGs
Type
journal article