Intercalation Chemistry of Ionic Liquids

摘要

The use of ionic liquids as electrolytes for the intercalation of TiS_2by Li~+ and Mg~(++) has been studied using a short chain and longchain substituted imidazolium based ionic liquid: 1,2-dimethyl-3-n-propylimidazolium and 1,2-dimethyl-3-n-ocylimidazolium, bothpaired with the bis(trifluoromethanesulfonyl)imide anion. Resultsindicate co-intercalation of the shorter chain ionic liquid with theLi~+ cation, while intercalation into TiS_2 was not observed for thelonger chain ionic liquid. For the longer chain system,intercalation of TiS_2 by both Li~+ and Mg~(++) is observed.Intercalation behavior is characterized by electrochemical and xraypowder diffraction studies of the intercalates. Charge/dischargeefficiencies for the shorter chain ionic liquid were typically below50%, likely due to co-intercalation of the ionic liquid itself.Charge/discharge experiments of Li~+ and Mg~(++) intercalation intoTiS_2 using the longer chain ionic liquid resulted in efficienciesover 90 %.