T0501-1-6 Numerical Analyses on Electric Double Layer and Electroosmotic Flow in Nano-Scale Parallel Plates

Abstract

Molecular dynamics analyses have been performed on the electricosmotic flow in parallel plates. Though positive ions move over the whole region in the case of a channel width of 〜8 nm suggesting the overlap of electric double layer, positive ions travel within the regions near the channel walls in the case of a channel width of 〜20 nm suggesting the formation of electric double layer near the channel walls. Also, a fully-developed electroosmotic flow is analyzed based on Gouy-Chapman model by the finite difference method. The distributions of positive ion density for fully-developed flow by the finite difference method agree with in some degree the trajectories of positive ions by the molecular dynamics. The electroosmotic flow velocity estimated by the finite difference method is 2.5 mm/s and 3.6 mm/s for channel widths of 〜8 nm and 〜20 nm, respectively.