Ohshima Hiroyuki
Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba, Japan.
Electrophoresis. 2022 Nov;43(21-22):2260-2266. doi: 10.1002/elps.202200035. Epub 2022 Apr 30.
An analytic expression is obtained for the diffusiophoretic mobility of a charged spherical colloidal particle in a symmetrical electrolyte solution. The obtained expression, which is expressed in terms of exponential integrals, is correct to the third order of the particle zeta potential so that it is applicable for colloidal particles with low and moderate zeta potentials at arbitrary values of the electrical double-layer thickness. This is an improvement of the mobility formula derived by Keh and Wei, which is correct to the second order of the particle zeta potential. This correction, which is related to the electrophoresis component of diffusiophoresis, becomes more significant as the difference between the ionic drag coefficients of electrolyte cations and anions becomes larger and vanishes in the limit of thin or thick double layer. A simpler approximate mobility expression is further obtained that does not involve exponential integrals.
得到了带电球形胶体粒子在对称电解质溶液中的扩散电泳迁移率的解析表达式。所得到的表达式用指数积分表示，在粒子zeta电位的三阶精度内是正确的，因此适用于任意双电层厚度下具有低和中等zeta电位的胶体粒子。这是对Keh和Wei推导的迁移率公式的改进，后者在粒子zeta电位的二阶精度内是正确的。这种与扩散电泳的电泳分量相关的修正，随着电解质阳离子和阴离子的离子曳力系数之差变得更大而变得更加显著，并在薄或厚双电层的极限情况下消失。进一步得到了一个不涉及指数积分的更简单的近似迁移率表达式。
