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dc.contributor.authorBazant, Martin Z.
dc.contributor.authorBiesheuvel, P. M.
dc.date.accessioned2010-06-02T19:55:22Z
dc.date.available2010-06-02T19:55:22Z
dc.date.issued2010-03
dc.date.submitted2009-11
dc.identifier.issn1550-2376
dc.identifier.issn1539-3755
dc.identifier.urihttp://hdl.handle.net/1721.1/55372
dc.description.abstractThe rapid and efficient exchange of ions between porous electrodes and aqueous solutions is important in many applications, such as electrical energy storage by supercapacitors, water desalination and purification by capacitive deionization, and capacitive extraction of renewable energy from a salinity difference. Here, we present a unified mean-field theory for capacitive charging and desalination by ideally polarizable porous electrodes (without Faradaic reactions or specific adsorption of ions) valid in the limit of thin double layers (compared to typical pore dimensions). We illustrate the theory for the case of a dilute, symmetric, binary electrolyte using the Gouy-Chapman-Stern (GCS) model of the double layer, for which simple formulae are available for salt adsorption and capacitive charging of the diffuse part of the double layer. We solve the full GCS mean-field theory numerically for realistic parameters in capacitive deionization, and we derive reduced models for two limiting regimes with different time scales: (i) in the “supercapacitor regime” of small voltages and/or early times, the porous electrode acts like a transmission line, governed by a linear diffusion equation for the electrostatic potential, scaled to the RC time of a single pore, and (ii) in the “desalination regime” of large voltages and long times, the porous electrode slowly absorbs counterions, governed by coupled, nonlinear diffusion equations for the pore-averaged potential and salt concentration.en
dc.language.isoen_US
dc.publisherAmerican Physical Societyen
dc.relation.isversionofhttp://dx.doi.org/10.1103/PhysRevE.81.031502en
dc.rightsArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.en
dc.sourceAPSen
dc.titleNonlinear dynamics of capacitive charging and desalination by porous electrodesen
dc.typeArticleen
dc.identifier.citationBiesheuvel, P. M., and M. Z. Bazant. “Nonlinear dynamics of capacitive charging and desalination by porous electrodes.” Physical Review E 81.3 (2010): 031502. © 2010 The American Physical Societyen
dc.contributor.departmentMassachusetts Institute of Technology. Department of Chemical Engineeringen_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Mathematicsen_US
dc.contributor.approverBazant, Martin Z.
dc.contributor.mitauthorBazant, Martin Z.
dc.relation.journalPhysical Review Een
dc.eprint.versionFinal published versionen
dc.type.urihttp://purl.org/eprint/type/JournalArticleen
eprint.statushttp://purl.org/eprint/status/PeerRevieweden
dspace.orderedauthorsBiesheuvel, P. M.; Bazant, M. Z.en
mit.licensePUBLISHER_POLICYen


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