Thermal stability of imidazolium-based ionic liquids


  • Léa Chancelier UMR CNRS 5265, C2P2, University of Lyon, 43 bd du 11 novembre 1918, F-69100 Villeurbanne
  • Olivier Boyron UMR CNRS 5265, C2P2, University of Lyon, 43 bd du 11 novembre 1918, F-69100 Villeurbanne
  • Thibaut Gutel CEA, LITEN, 17 rue des martyrs, F-38000 Grenoble
  • Catherine Santini Université de Lyon, Institut de Chimie de Lyon, UMR 5265 CNRS-Université de Lyon 1-ESCPE Lyon, LC2P2, Equipe Chimie Organométallique de Surface,



thermal stability, anion effect, alkyl chain length, functionalization


This work highlights the factors tuning the thermal stability of imidazolium-based ionic liquids (IL) associated to bis(trifluoromethanesulfonyl)imide anion [NTf2]. The decomposition temperatures (Td) were evaluated by thermogravimetric analyses (TGA) with optimized parameters to obtain reproducible Td. The impact of the alkyl chain length and of the presence of functional groups and unsaturations on Td were evaluated. The thermal behaviour was governed by Van der Waals interactions between alkyl chains, and by inter and intra coulombic interactions such as hydrogen bonds.


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