Huang, D.Cottin-Bizonne, C.Ybert, C.Bocquet, L.2011-06-212011-06-212008Physical Review Letters, 2008; 101(6):1-40031-90071079-7114http://hdl.handle.net/2440/64734We study electro- and diffusio-osmosis of aqueous electrolytes at superhydrophobic surfaces by means of computer simulation and hydrodynamic theory. We demonstrate that the diffusio-osmotic flow at superhydrophobic surfaces can be amplified by more than 3 orders of magnitude relative to flow in channels with a zero interfacial slip. By contrast, little enhancement is observed at these surfaces for electro-osmotic flow. This amplification for diffusio-osmosis is due to the combined effects of enhanced slip and ion surface depletion or excess at the air-water interfaces on superhydrophobic surfaces. This effect is interpreted in terms of capillary driven Marangoni motion. A practical microfluidic pumping device is sketched on the basis of the slip-enhanced diffusio-osmosis at a superhydrophobic surface.en©2008 American Physical SocietyJournal article002010752110.1103/PhysRevLett.101.0645030002585386000232-s2.0-4974910626830171Huang, D. [0000-0003-2048-4500]