Electrophoretic Motion of a Spherical Particle with a Symmetric Nonuniform Surface Charge Distribution in a Nanotube

Authors

Shizhi Qian, University of Nevada, Las VegasFollow
Sang W. Joo, Yeungnam UniversityFollow
Wensheng Hou, Chongqing University
Xuxin Zhao, Shenzhen University

Document Type

Article

Publication Date

2008

Publication Title

Langmuir

Volume

24

Issue

10

First page number:

5332

Last page number:

5340

Abstract

The electrophoretic motion of a spherical nanoparticle, subject to an axial electric field in a nanotube filled with an electrolyte solution, has been investigated using a continuum theory, which consists of the Nernst–Planck equations for the ionic concentrations, the Poisson equation for the electric potential in the solution, and the Stokes equation for the hydrodynamic field. In particular, the effects of nonuniform surface charge distributions around the nanoparticle on its axial electrophoretic motion are examined with changes in the bulk electrolyte concentration and the surface charge of the tube’s wall. A particle with a nonuniform charge distribution is shown to induce a corresponding complex ionic concentration field, which in turn influences the electric field and the fluid motion surrounding the particle and thus its electrophoretic velocity. As a result, contrary to the relatively simple dynamics of a particle with a uniform surface charge, dominated by the irradiating electrostatic force, that with a nonuniform surface charge distribution shows various intriguing behaviors due to the additional interplay of the nonuniform electro-osmotic effects.

Keywords

Electro-osmosis; Electrodynamics; Electrolyte solutions; Electrophoresis; Ion flow dynamics; Microfluidics; Nanoparticles; Nanotubes; Surface energy

Disciplines

Acoustics, Dynamics, and Controls | Electrical and Computer Engineering | Fluid Dynamics | Mechanical Engineering | Nanoscience and Nanotechnology

Language

English

Permissions

Use Find in Your Library, contact the author, or interlibrary loan to garner a copy of the item. Publisher policy does not allow archiving the final published version. If a post-print (author's peer-reviewed manuscript) is allowed and available, or publisher policy changes, the item will be deposited.

Repository Citation

Qian, S., Joo, S. W., Hou, W., Zhao, X. (2008). Electrophoretic Motion of a Spherical Particle with a Symmetric Nonuniform Surface Charge Distribution in a Nanotube. Langmuir, 24(10), 5332-5340.