Electrophoresis of Conducting and Nonconducting Microparticles in a Polar Electrolyte under a Strong Electric Field

This work is devoted to studying electrophoresis of conducting and nonconducting particles in a polar electrolyte solution under the action of a strong electric field. Numerical simulation results are presented for both types of particles, including distributions of cation and anion concentrations, charge densities, and total concentrations and fluxes of ions near the particle surface. It is shown that an extended spatial charge region arises near a dielectric surface at a sufficiently high surface charge. This region is formed due to a high surface conductivity in the electrical double layer and intense tangential ion fluxes. Qualitative differences are revealed between the the mechanisms of extended spatial charge formation for ion-selective and dielectric particles. The results obtained facilitate understanding the nonlinear electrokinetic processes and can be useful for designing microliquidic systems and colloidal technologies.