Dynamics of fluorinated imide-based ionic liquids using nuclear magnetic resonance techniques.

There is increasing interest in studying molecular motions in ionic liquids to gain better insights into their transport properties and to expand their applications. In this study, we have employed the fast field cycling relaxometry and pulsed field gradient nuclear magnetic resonance techniques to investigate the rotational and translational dynamics of fluorinated imide-based ionic liquids (ILs) at different temperatures. We have studied a total of six ILs composed of the 1-butyl-3-methylimidazolium cation ([BMIM]) combined with chemically modified analogs of the bis((trifluoromethyl)sulfonyl)imide anion ([NTf] or [TFSI]).

Increasing Cation Ion Symmetry Reduces Ionic Liquid Ordering in Thin Films.

Ionic liquids have been shown to form extended ordered structures near surfaces and in bulk. Identifying fundamental driving force(s) for this organization has been elusive. In this paper, we test a hypothesis that the ionic liquid asymmetry, inherent in many of the IL formulations to frustrate crystallization, is a significant contributor to the observed ordering.

Evolving better solvate electrolytes for lithium secondary batteries.

The overall performance of lithium batteries remains unmatched to this date. Decades of optimisation have resulted in long-lasting batteries with high energy density suitable for mobile applications. However, the electrolytes used at present suffer from low lithium transference numbers, which induces concentration polarisation and reduces efficiency of charging and discharging.