Overlimiting Current in a Microchannel
Open Access
- 6 September 2011
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 107 (11), 118301
- https://doi.org/10.1103/physrevlett.107.118301
Abstract
We revisit the classical problem of diffusion-limited ion transport to a membrane (or electrode) by considering the effects of charged sidewalls. Using simple mathematical models and numerical simulations, we identify three basic mechanisms for overlimiting current in a microchannel: (i) surface conduction carried by excess counterions, which dominates for very thin channels, (ii) convection by electro-osmotic flow on the sidewalls, which dominates for thicker channels, and (iii) transitions to electro-osmotic instability on the membrane end in very thick channels. These intriguing electrokinetic phenomena may find applications in biological separations, water desalination, and electrochemical energy storage. DOI: http://dx.doi.org/10.1103/PhysRevLett.107.118301 Received 7 February 2011Published 6 September 2011© 2011 American Physical SocietyKeywords
This publication has 29 references indexed in Scilit:
- Intensive current transfer in membrane systems: Modelling, mechanisms and application in electrodialysisAdvances in Colloid and Interface Science, 2010
- Selection of Nonequilibrium Overlimiting Currents: Universal Depletion Layer Formation Dynamics and Vortex InstabilityPhysical Review Letters, 2008
- Direct Observation of a Nonequilibrium Electro-Osmotic InstabilityPhysical Review Letters, 2008
- Electro-osmotic slip and electroconvective instabilityJournal of Fluid Mechanics, 2007
- Electrochemical Thin Films at and above the Classical Limiting CurrentSIAM Journal on Applied Mathematics, 2005
- Experimental Verification of the Electroosmotic Mechanism of Overlimiting Conductance Through a Cation Exchange Electrodialysis MembraneRussian Journal of Electrochemistry, 2002
- Electro-osmotically induced convection at a permselective membranePhysical Review E, 2000
- Physicochemical HydrodynamicsPublished by Wiley ,1994
- Voltage against current curves of cation exchange membranesJournal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Physics, 1979
- Double layer structure at the limiting currentTransactions of the Faraday Society, 1967