Colloid transport by an oscillatory electroosmotic flow between microelectrodes of axially variable shape

Abstract

In this work, an analytic solution for the hydrodynamic dispersion of silver colloidal nanoparticles released into an oscillatory electroosmotic flow between microelectrodes of axially variable shape is presented. The long-time colloid concentration response is derived using the homogenization method together with multiple-scale analysis. The results indicate that the deposition of nanoparticles onto the surface of the microelectrodes depends on the rate constant β of solute reaction at the wall, on the angular frequency ω, and mainly on the induced pressure gradient that arises due to the variable geometrical shape of the walls. For suitable values of the previous parameters, we show that colloidal nanoparticle concentration can be enhanced as well as choosing the location where it will happen.