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Title: Capillary evaporation of the ionic liquid [EMIM][BF4] in nanoscale solvophobic confinement

Journal Article · · Journal of Chemical Physics
DOI:https://doi.org/10.1063/1.5010259· OSTI ID:1470140

We report that solvent density fluctuations play a crucial role in liquid-vapor transitions in solvophobic confinement and can also be important for understanding solvation of polar and apolar solutes. In the case of ionic liquids (ILs), density fluctuations can be used to understand important processes in the context of nanoscale aggregation and colloidal self-assemblies. In this article, we explore the nature of density fluctuations associated with capillary evaporation of the IL 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) in the confined region of model solvophobic nanoscale sheets by using molecular dynamics simulations combined with non-Boltzmann sampling techniques. We demonstrate that density fluctuations of the confined IL play an important role in capillary evaporation, suggesting analogies to dewetting transitions involving water. Lastly, significant changes in the interfacial structure of the IL are also detailed and suggested to underlie a non-classical (non-parabolic) dependence of the free energy barrier to evaporation on the degree of confinement.

Research Organization:
Energy Frontier Research Centers (EFRC) (United States). Center for the Computational Design of Functional Layered Materials (CCDM)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0012575
OSTI ID:
1470140
Alternate ID(s):
OSTI ID: 1418409
Journal Information:
Journal of Chemical Physics, Vol. 148, Issue 19; Related Information: CCDM partners with Temple University (lead); Brookhaven National Laboratory; Drexel University; Duke University; North Carolina State University; Northeastern University; Princeton University; Rice University; University of Pennsylvania; ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 13 works
Citation information provided by
Web of Science

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Cited By (4)

Preface: Special Topic on Chemical Physics of Ionic Liquids journal May 2018
Does capillary evaporation limit the accessibility of nonaqueous electrolytes to the ultrasmall pores of carbon electrodes? journal December 2018
Wettability of ultra-small pores of carbon electrodes by size-asymmetric ionic fluids journal February 2020
Molecular dynamics investigation of wetting-dewetting behavior of model carbon material by 1-butyl-3-methylimidazolium acetate ionic liquid nanodroplet journal December 2019

Figures / Tables (4)