Physicochemical properties of trialkylphosphonium-based protic ionic liquids

Abstract

Novel room-temperature ionic liquids based on trialkylphosphonium cations and their physicochemical characterizations are presented in this report. It was found that ionic liquids based on trialkylphosphonium cations together with bis(trifluoromethylsulfonyl)amide anion were lower melting, lower viscous and more conductive than the corresponding trialkylammonium ionic liquids. Particularly, triethylphosphonium bis(trifluoromethylsulfonyl)amide exhibited the lowest viscosity and highest conductivity in the trialkylphosphonlum-based ionic liquids. The protic ionic liquid electrolyte based on triethylphosphonium bis(trifluoromethylsulfonyl)amide also showed relatively high conductivity when compared to the corresponding ammonium ionic liquid electrolyte. © The Electrochemical Society of Japan. All rights reserved.