A comparative study of room temperature ionic liquids and their organic solvent mixtures near charged electrodes

Vatamanu, Jenel; Vatamanu, Mihaela; Borodin, Oleg; Bedrov, Dmitry

doi:10.1088/0953-8984/28/46/464002

Cited by 35 publications

(45 citation statements)

References 141 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…25,[25][26][27] Wang et al's implementation operates through the use of the LAMMPS molecular dynamics software. 28 In addition to the aforementioned study by Li et al the constant potential method was previously used in simulations of ionic liquids 29,30 as well as of lithium-based electrolytes. 26 The constant potential method works by fixing the electric potential (Ψ i ) on each electrode atom so that it is equal to the external potential (V ).…”

Section: Methodsmentioning

confidence: 99%

Simulation of a Solvate Ionic Liquid at a Polarizable Electrode with a Constant Potential

Coles

Ivaništšev

2019

J. Phys. Chem. C

View full text Add to dashboard Cite

Solvate ionic liquids have the potential for use in a wide range of electrochemical devices. The interfacial nanostructure of these liquids largely determines the performance of such applications. In this work we have focused on the nanostructure and calculated the capacitance of a solvate ionic liquid-electrode interface, where the electrode has a constant potential, and is thus inherently polarisable. The first time, to our knowledge, a solvate ionic liquid has been simulated at such an electrode. Lithium cations from the lithium-glyme solvate ionic liquid are found within 0.5 nm of the electrode at all voltages studied, however, their solvation environment varies with voltage, with both lithium cation-anion and lithium cation-glyme complexes being observed in the first interfacial layer. Our study provides molecular insight into the electrode interface of solvate ionic liquids, with many features similar to pure ionic liquids. The profound differences between the structure observed in these simulations and 1 our previous study performed with fixed charge electrode boundary conditions make clear the importance of accurate modelling interfaces when studying solvate ionic liquids. The differences shown here are qualitatively greater than observed for conventional ionic liquids.

show abstract

Section: Methodsmentioning

confidence: 99%

Simulation of a Solvate Ionic Liquid at a Polarizable Electrode with a Constant Potential

Coles

Ivaništšev

2019

J. Phys. Chem. C

View full text Add to dashboard Cite

show abstract

“…At the opposite end of the concentration spectrum -when ions are diluted to < mM concentration in a polar solvent such as water -the resulting electrical double layer structure is of course well described by classical Stern and Gouy-Chapmann models [5]. Only a few recent experimental [6][7][8][9][10] and simulation [11,12] studies have focussed on the intermediate concentration regime where neither ions nor solvent are in great excess.…”

Section: Introductionmentioning

confidence: 99%

Interfacial structure and structural forces in mixtures of ionic liquid with a polar solvent

et al. 2018

View full text Add to dashboard Cite

Many applications of ionic liquids involve their mixtures with neutral molecular solvents. The chemical physics of these high-concentration electrolytes, in particular at interfaces, still holds many challenges. In this contribution we begin to unravel the relationship between measurements of structural ('solvation') forces in mixtures of ionic liquid with polar solvent and the corresponding structure determined by molecular dynamics simulations of the same mixtures. In order to make the quantitative link between experiments with mica surfaces and simulations with fixed-charge surfaces, we present an experimental procedure for determining the effective surface charge on mica in ionic liquid. We find that a structural cross-over recently inferred from force measurements appears to be supported by the simulations: at the cross-over, the charge-oscillatory structure switches to charge-monotonic, and solvent layering becomes dominant. Finally, we map out a phase diagram in composition-surface charge space delineating regions of charge-oscillatory interfacial structure and regions of charge-monotonic decay. We note that these features of structure and oscillatory forces are distinct from (acting simultaneously with) the recently reported longer range monotonic forces arising from anomalously long bulk screening lengths in high-concentration electrolytes.

show abstract

“…The simulations are performed using the constant potential method implemented by Wang et al 6 based on previous work by Reed et al, 7 Gingrich et al, 8 and Siepmann et al 9 This implementation operates through the use of the LAMMPS molecular dynamics software. 10 Similar methods were previously used in several simulations of ionic liquids 11,12 as well as of lithium-based electrolytes. 13 Force fields used for the ionic liquid were developed by Shimizu et al, 14 and are the same as used in our previous study.…”

Section: Methodsmentioning

confidence: 99%

Simulation of a Solvate Ionic Liquid at a Polarisable Electrode with a Constant Potential

Coles¹,

Ivaništšev²

2018

Preprint

View full text Add to dashboard Cite

<div>In this article we discuss the nanostructure and calculated the capacitance of a solvate ionic liquid–electrode interfaces, where the electrode has a constant potential, and is thus inherently polarisable. Lithium ions from the lithium</div><div>glyme solvate ionic liquid are found within 0.5 nm of the electrode at all voltages studied, however, their solvation environment varies with voltage. Our study provides molecular insight into the electrode interface of solvate ionic liquids, with many features similar to pure ionic liquids. A comparison with previous studies of the same electrolyte using the fixed surface charge boundary condition is also illuminating, informing future computational studies of electrolyte–electrode interfaces.</div>

show abstract

A comparative study of room temperature ionic liquids and their organic solvent mixtures near charged electrodes

Cited by 35 publications

References 141 publications

Simulation of a Solvate Ionic Liquid at a Polarizable Electrode with a Constant Potential

Simulation of a Solvate Ionic Liquid at a Polarizable Electrode with a Constant Potential

Interfacial structure and structural forces in mixtures of ionic liquid with a polar solvent

Simulation of a Solvate Ionic Liquid at a Polarisable Electrode with a Constant Potential

Contact Info

Product

Resources

About