title: Synthesis and characterization of 5-cyanotetrazolide-based ionic liquids.
abstract: New salts based on imidazolium, pyrrolidinium, phosphonium, guanidinium, and ammonium cations together with the 5-cyanotetrazolide anion [C2 N5 ](-) are reported. Depending on the nature of cation-anion interactions, characterized by XRD, the ionic liquids (ILs) have a low viscosity and are liquid at room temperature or have higher melting temperatures. Thermogravimetric analysis, cyclic voltammetry, viscosimetry, and impedance spectroscopy display a thermal stability up to 230 °C, an electrochemical window of 4.5 V, a viscosity of 25 mPa s at 20 °C, and an ionic conductivity of 5.4 mS cm(-1) at 20 °C for the IL 1-butyl-1-methylpyrrolidinium 5-cyanotetrazolide [BMPyr][C2 N5 ]. On the basis of these results, the synthesized compounds are promising electrolytes for lithium-ion batteries.
authors.affiliation: Institute of Energy and Climate Research, Electrochemical Process Engineering (IEK 3), Forschungszentrum Jülich, Leo-Brandt Strasse, 52425 Jülich (Germany). t.bergholz@fz-juelich.de.
authors.forename: Timm
authors.initials: T
authors.lastname: Bergholz
authors.forename: Benjamin
authors.initials: B
authors.lastname: Oelkers
authors.forename: Benedikt
authors.initials: B
authors.lastname: Huber
authors.forename: Bernhard
authors.initials: B
authors.lastname: Roling
authors.forename: Jörg
authors.initials: J
authors.lastname: Sundermeyer
keywords: anions; azides; cations; ionic liquids; protonation