A periodic array of nano-scale parallel slats for high-efficiency electroosmotic pumping.

摘要: It is known that the eletroosmotic (EO) flow rate through a nano-scale channel extremely small. A made of periodic array slats proposed to effectively promote EO pumping, and thus greatly improve rate. The geometrically simple complicated enough four length scales are involved: vertical period 2L, lateral 2aL, width slat 2cL as well Debye λD. pumping determined by normalized lengths: a, c, or perforation fraction η=1-(c/a) dimensionless electrokinetic K=L/λD. In channel, K order unity less. in both longitudinal transverse directions (denoted (LEOP) (TEOP), respectively) investigated solving Debye-Huckel approximation viscous electro-kinetic equation. main findings include (i) rates LEOP for small remarkably improved (by one magnitude) when we have longer (a≫1) large (η > 0.7); (ii) TEOP can also be much but less significantly with slats. Nevertheless, it must noted practice cannot arbitrarily criterion φc≈0 reference potential at center put lower bounds on K; other words, there geometrical limits use Poisson-Boltzmann