Combination of organic cation and cyclic sulfonylamide anion exhibiting plastic crystalline behavior in a wide temperature range

Organic ionic plastic crystals (OIPCs) with cyclic perfluoroalkyl sulfonylamide as a counter anion were synthesized with an intention of expanding the temperature range of their plastic crystalline phase. The thermal analysis of the obtained OIPCs showed a solid–solid phase transition below room temperature and a high melting point above 250 °C, that indicated their plastic crystalline behavior in a wide temperature range, as well as thermal durability up to approximately 370 °C. The electrochemical measurements of these OIPCs revealed the solid-state ionic conductivity of the plastic crystalline phase and a wide electrochemical window between 0.4 and 6.2 V vs. Li/Li+.