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Near-Wall Molecular Ordering of Dilute Ionic Liquids.

ABSTRACT: The interfacial behavior of ionic liquids promises tunable lubrication as well as playing an integral role in ion diffusion for electron transfer. Diluting the ionic liquids optimizes bulk parameters, such as electric conductivity, and one would expect dilution to disrupt the near-wall molecular ordering. We study this ordering in the ionic liquids [Emim]⁺[NTf₂]^-, [Emim]⁺[DCA]^-, and [C₄mpyr]⁺[NTf₂]^-, diluted in the solvent dimethyl sulfoxide. We found a structural crossover from well-ordered ionic liquids to a well-ordered solvent with increasing dilution, but this occurs nonlinearly, with solvent molecules initially space-filling and solvating and later disrupting the ionic layers. This is of key importance for ionic liquids as optimized tunable nanolubricants.

SUBMITTER: Jitvisate M

PROVIDER: S-EPMC5582367 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Near-Wall Molecular Ordering of Dilute Ionic Liquids.

Jitvisate Monchai M Seddon James R T JRT

The journal of physical chemistry. C, Nanomaterials and interfaces 20170808 34

The interfacial behavior of ionic liquids promises tunable lubrication as well as playing an integral role in ion diffusion for electron transfer. Diluting the ionic liquids optimizes bulk parameters, such as electric conductivity, and one would expect dilution to disrupt the near-wall molecular ordering. We study this ordering in the ionic liquids [Emim]+[NTf2]-, [Emim]+[DCA]-, and [C4mpyr]+[NTf2]-</sup ...[more]

PMID: 28883896

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