Modeling electrokinetics in ionic liquids

Wang, Chao; Bao, Jie; Pan, Wenxiao; X, Sun

doi:10.1002/elps.201600455

Cited by 10 publications

(8 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The theory was used to describe electrosmotic 20 and electrophoretic mobility 21 reversals in multivalent and concentrated electrolytes, as well as electroconvective instabilities in ionic liquids. 22 It was also applied to the dynamics 23−27 and electrosorption 28−31 at electrochemical interfaces for ionic liquids and concentrated solvent-in-salt electrolytes, including storage 32 and transport 33 in nanoporous media. Electrostatic correlations have a profound effect on colloidal interactions, 4,34,35 where they can induce like-charge attraction in multivalent electrolytes, also predicted by the BSK theory.…”

Section: ■ Introductionmentioning

confidence: 99%

Continuum Theory of Electrostatic Correlations at Charged Surfaces

Souza

Bazant

2020

J. Phys. Chem. C

View full text Add to dashboard Cite

The standard model for diffuse charge phenomena in colloid science, electrokinetics, and biology is the Poisson−Boltzmann mean-field theory, which breaks down for multivalent ions and large surface charge densities because of electrostatic correlations. In this paper, we formulate a predictive continuum theory of correlated electrolytes based on two extensions of the Bazant− Storey−Kornyshev (BSK) framework: (i) a physical boundary condition enforcing continuity of the Maxwell stress at a charged interface, which upholds the contact theorem for dilute primitivemodel electrolytes, and (ii) scaling relationships for the correlation length, for a one-component plasma at a charged plane and around a cylinder, as well as a dilute z:1 electrolyte screening a planar surface. In these cases, the theory accurately reproduces Monte Carlo simulation results from weak to strong coupling, and extensions are possible for more complex models of electrolytes and ionic liquids.

show abstract

Section: ■ Introductionmentioning

confidence: 99%

Continuum Theory of Electrostatic Correlations at Charged Surfaces

Souza

Bazant

2020

J. Phys. Chem. C

View full text Add to dashboard Cite

show abstract

“…One can interpret this term as a phenomenological correction to the mean-field PB framework that is solved for in the mean field. This simple extension of the PB theory is a useful first approximation of ion–ion correlation effects in ionic liquids − and in so-called “water-in-salt” electrolytes …”

Section: Introductionmentioning

confidence: 99%

Theory of Surface Forces in Multivalent Electrolytes

et al. 2019

View full text Add to dashboard Cite

Aqueous electrolyte solutions containing multivalent ions exhibit various intriguing properties, including attraction between like-charged colloidal particles, which results from strong ion–ion correlations. In contrast, the classical Derjaguin–Landau–Verwey–Overbeek theory of colloidal stability, based on the Poisson–Boltzmann mean-field theory, always predicts a repulsive electrostatic contribution to the disjoining pressure. Here, we formulate a general theory of surface forces, which predicts that the contribution to the disjoining pressure resulting from ion–ion correlations is always attractive and can readily dominate over entropic-induced repulsions for solutions containing multivalent ions, leading to the phenomenon of like-charge attraction. Ion-specific short-range hydration interactions, as well as surface charge regulation, are shown to play an important role at smaller separation distances but do not fundamentally change these trends. The theory is able to predict the experimentally observed strong cohesive forces reported in cement pastes, which result from strong ion–ion correlations involving the divalent calcium ion.

show abstract

“…Note that the concentration yielding a thin double layer (∼3 nm at 10 mM) is much lower than the concentration having strong effects of finite ion size and ion-ion interactions (100-1000 M). These effects are typically important in ionic liquids and are better described by the modified Nernst-Planck-Poisson models (Bockris & Reddy 1998;Bazant, Storey & Kornyshev 2011;Wang et al 2017). In a relatively dilute electrolyte, the effects of a non-ideal solution are negligible, meanwhile the condition of a thin double layer is still valid.…”

Section: Governing Equations and Boundary Conditionsmentioning

confidence: 99%

Electroconvection near an ion-selective surface with Butler–Volmer kinetics

Townsend

Archer

et al. 2021

J. Fluid Mech.

View full text Add to dashboard Cite

We study the effects of interfacial kinetics on the electro-hydrodynamics of ion transport near an ion-selective surface using a combination of linear stability analysis and numerical simulation. The finite kinetics of the electrolyte–electrode interface affects the ion transfer and electroconvection in many ways. On a surface of fixed topography, such as a metal surface of slow and stable ion deposition or covered by a polymer membrane, the finite kinetics reduces the current in one-dimensional ion diffusion/migration, increases the critical voltage for the onset of the electroconvective instability, changes the dynamics of the electroconvection and the overlimiting current, and enhances the lateral ion diffusion within the interfacial layer. The first three effects are indirectly caused by the reaction kinetics and can be characterized by an effective voltage difference across the liquid electrolyte. In comparison, the last effect is controlled by a direct interplay between kinetics and nonlinear electroconvection. Scaling laws for ion transport and features of electroconvection are proposed. We also analyse the linear stability of a surface which evolves under ion deposition and find that the finite kinetics decreases the growth rate of both electroconvective and morphological instabilities and therefore modifies the wavenumber of the most unstable mode.

show abstract

Modeling electrokinetics in ionic liquids

Cited by 10 publications

References 59 publications

Continuum Theory of Electrostatic Correlations at Charged Surfaces

Continuum Theory of Electrostatic Correlations at Charged Surfaces

Theory of Surface Forces in Multivalent Electrolytes

Electroconvection near an ion-selective surface with Butler–Volmer kinetics

Contact Info

Product

Resources

About