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DOE OSTI · 1657652

Molecular-Level Behavior of Imidazolium-Based Ionic Liquid Mixtures

Sappidi, Praveenkumar·Bara, Jason E.·Turner, C. Heath
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Abstract

Understanding the molecular-level organization of anions and cations in a mixture of different ionic liquids (ILs) is challenging, but it can be very important for designing solvents and IL-based membrane materials. In this work, we perform all-atom molecular dynamics (MD) simulations to understand the intermolecular interactions and structuring of both neat and mixed IL compositions containing 1-benzyl-3-methylimidazolium [ZMIM + ], 1-butyl-3-methylimidazolium [BMIM + ], bistriflimide [Tf 2 N – ], and tetrafluoroborate [BF 4 – ]. We observe very strong underlying molecular-level migrations in these mixtures, and this tends to mainly involve the anion species. As compared to the systems with a single anion, the mixed anions lead to large increases/decreases in the radial distribution function peak heights, whereas the cation mixing is relatively benign. The [BF 4 – ] anions have a strong tendency to displace the [Tf 2 N – ] anions in the mixtures, and this is seen with respect to both [BMIM + ] and [ZMIM + ].

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYAnionsImidazoliumIonic liquidMD simulationMixture

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Sappidi, Praveenkumar, Bara, Jason E., Turner, C. Heath. 2020-08-27. Molecular-Level Behavior of Imidazolium-Based Ionic Liquid Mixtures. https://doi.org/10.1016/j.ces.2020.116073

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