Anion receptor based on cyclic siloxanes substituted with trifluoromethane-sulfonylamide for solid polymer electrolytes

Abstract

An anion receptor based on cyclic siloxanes substituted with trifluoromethane-sulfonylamide was prepared to enhance the ionic conductivity of the solid polymer electrolytes. The anion receptor contains four anioncomplexing sites at its peripherals and bears a geometry with low steric hindrance, which makes the anions access and bind easily. The anion receptor effectively enhanced the ionic conductivity of the polymer electrolyte containing LiCl by two orders of magnitude and LiCF(3)SO(3) by one order. The experimental results showed that the anion receptors trap the anions in a one-to-one coordination between the anion-complexing site and anion. The highest ionic conductivity was observed at the lowest activation energy, which was estimated from the VTF plot. The anion receptor was found to be electrochemically stable up to 5 V, which is suitable for a lithium polymer battery.