title: Electrolyte stability in a nanochannel with charge regulation.
abstract: The stability of an electrolyte confined in one dimension between two solid surfaces is analyzed theoretically in the case where overlapping double layers produce nontrivial interactions. Within the Poisson-Boltzmann-Nernst-Planck description of the electrostatic interaction and transport of electrical charges, the presence of Stern layers can enrich the set of possible solutions. Our analytical and numerical study of the stability properties of the trivial state of this system identified an instability to a new antisymmetric state. This state is stable for a range of gap widths that depends on the Debye and Stern lengths, but for smaller gap widths, where the Stern layers overlap, a second transition takes place and the stable nontrivial solution diverges. The origin of this divergence is explained and its properties analyzed using asymptotic techniques which are in good agreement with numerical results. The relevance of our results to confined electrolytes at nanometer scales is discussed in the context of energy storage in nanometric systems.
authors.affiliation: Université de Toulouse, INP, and CNRS, IMFT (Institut de Mécanique des Fluides de Toulouse), Allée Camille Soula, F-31400 Toulouse, France. cedric.beaume@imft.fr
authors.forename: Cédric
authors.initials: C
authors.lastname: Beaume
authors.forename: Franck
authors.initials: F
authors.lastname: Plouraboué
authors.forename: Alain
authors.initials: A
authors.lastname: Bergeon
authors.forename: Edgar
authors.initials: E
authors.lastname: Knobloch