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DOE OSTI · 1648050

NMR Relaxometry and Diffusometry Analysis of Dynamics in Ionic Liquids and Ionogels for Use in Lithium-Ion Batteries

Jayakody, Nishani Kanchana·Fraenza, Carla C.·Greenbaum, Steven G.·Ashby, David·Dunn, Bruce S.
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Abstract

Solvation and transport properties of methlyviologen dichloride in mixtures of choline chloride (ChCl) and ethylene glycol (EG) including the deep eutectic solvent (DES) ethaline were studied through physical property measurements, cyclic voltammetry, and Raman spectroscopy. The transport properties of the solvate structures in ethaline and ChCl:EG mixtures were compared to a well-studied ionic liquid (IL), 1-methyl-1-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [PYR13][TFSI] through the lens of hole theory. Exchanging the chloride anion of ethaline with bis(trifuoromethylsufonyl)imide) anion, [TFSI], is found to increase the fluidity of the solvent and promoted stronger solute-solvent interactions. Raman spectroscopy shows that methylviologen is solvated by EG in solutions with ChTFSI but interstitially accommodated in void spaces in both ChCl solutions and [PYR13][TFSI]. Complex solvents such as DESs are regarded as “designer solvents” and we demonstrate that the physical properties and solvation characteristics of these fluids can be varied by anion exchange of hydrogen bond acceptors.

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Jayakody, Nishani Kanchana, Fraenza, Carla C., Greenbaum, Steven G., Ashby, David, Dunn, Bruce S.. 2020-07-15. NMR Relaxometry and Diffusometry Analysis of Dynamics in Ionic Liquids and Ionogels for Use in Lithium-Ion Batteries. https://doi.org/10.1021/acs.jpcb.0c02755

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