Physicochemical Properties of Bis(fluorosulfonyl)amide-Based Ionic Liquids Mixed with Mg and Sr Doped Cubic Li₇La₃Zr₂O₁₂ Powder

Abstract

Physicochemical properties of bis(fluorosulfonyl)amide anion-based ionic liquids (ILs) adsorbed on solid oxide electrolyte powder of cubic Li₇La₃Zr₂O₁₂ (LLZ) partially substituted by Mg and Sr were evaluated. In this study, an experimental system that ion does not pass the interface between LLZ and IL was selected by using ILs without lithium salt in order to elucidate the properties of adsorbed ILs layer. We prepared mixtures of LLZ with 1-methyl-1-propylpyrrolidinium bis(fluorosulfonyl)amide and 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)amide of various average IL thickness on LLZ particles by changing the IL volume per LLZ surface area. Evaluation of ionic conductivity and thermal property, and measurement of nuclear magnetic resonance spectra of these samples were performed. The results indicate the existence of an IL adsorption layer on the LLZ surface that shows solid-like behavior.