Structurally Flexible Pyrrolidinium- and Morpholinium-based Ionic Liquid Electrolytes

Ion transport measures and details as well as physico-chemical and electrochemical properties are presented for a small set of structurally flexible pyrrolidinium (Pyrr) and morpholinium (Morph) cation-based ionic liquids (ILs), all with oligoether phosphate-based anions. All have high thermal stabilities, low glass transition temperatures, and wide electrochemical stability windows, but rather moderate ionic conductivities, whereas both the anions and the cations of the Pyrr-based ILs diffuse faster than those of the Morph-based ILs. Overall the former ILs have significantly more promise as high-temperature supercapacitor electrolytes, rendering a specific capacitance of 164 F g−1 at 1 mV s−1, a power density of 241 W kg−1 and a specific energy density of 30 Wh kg−1 at 90 °C in a symmetric graphite supercapacitor.
Validerad;2023;Nivå 2;2023-08-17 (joosat);Licens fulltext: CC BY 3.0