Fluctuation-enhanced electric conductivity in electrolyte solutions

Journal Article · Tue Sep 26 00:00:00 EDT 2017 · Proceedings of the National Academy of Sciences of the United States of America

DOI:https://doi.org/10.1073/pnas.1714464114· OSTI ID:1396062

Péraud, Jean-Philippe ^[1]; Nonaka, Andrew J. ^[1]; Bell, John B. ^[1]; Donev, Aleksandar ^[2]; Garcia, Alejandro L. ^[3]

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1. Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94703,
2. Department of Mathematics, Courant Institute of Mathematical Sciences, New York University, New York, NY 10012,
3. Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192

Significance

Using fluctuating hydrodynamics, we demonstrate that thermal fluctuations contribute to charge transport in binary electrolyte solutions. We show the existence of an enhancement, or renormalization, of the electric conductivity due to the coupling between fluctuations of charge and fluid velocity. This coupling results in nontrivial corrections to the classical Poisson–Nernst–Planck equations, which are of the order of the square root of the salt concentration and therefore significant even for dilute solutions. Our calculations predict a cation–anion cross-diffusion coefficient that is in quantitative agreement with experimental measurements. Our findings have important implications for the fields of both mesoscale hydrodynamics and electrolyte transport.

• Sponsoring Organization: USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)
• Grant/Contract Number: AC02-05CH11231; SC0008271
• OSTI ID: 1396062
• Alternate ID(s): OSTI ID: 1426738
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 41 Vol. 114; ISSN 0027-8424
• Publisher: Proceedings of the National Academy of Sciences
• Country of Publication: United States
• Language: English