Ethyl-dimethyl-(ferrocenylmethyl)ammonium-based ionic liquid: Structure, transport, and electrochemical properties of binary solutions in acetonitrile
摘要
This work reports the synthesis and comprehensive physicochemical characterization of ethyl-dimethyl-(ferrocenylmethyl)ammonium bis(trifluoromethylsulfonyl)imide ([Fc1N112][NTf2]) ionic liquid—a promising electrolyte component of redox-flow batteries. The structure of [Fc1N112][NTf2] was analyzed by XRD, NMR, and XPS. The ionic conductivities of [Fc1N112][NTf2] solutions in acetonitrile were measured in the temperature range of 298–348 K and analyzed using the Casteel-Amis, Arrhenius, and Vogel-Fulcher-Tamman equations. The thermo-gravimetric analysis confirmed the high thermal stability of [Fc1N112][NTf2] up to 570 K. The densities of the [Fc1N112][NTf2] binary solutions were measured, and the coefficients of thermal expansion were calculated. Electrochemical stability of [Fc1N112][NTf2] was tested by cyclic voltammetry using [EMIm][NTf2] as a supporting electrolyte. A large electrochemical stability window of 5.38 V was detected.