title: Rationale for the implementation of reference electrodes in ionic liquids.
abstract: A thorough investigation of the reference electrodes for electrochemical measurements is presented in three ionic liquids (ILs), namely 1-butyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide [BMIM][Tf2N], 1-octyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide [OMIM][Tf2N] and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide [BMPyrr][Tf2N]. The influence of technical aspects such as internal resistance, scan rate and concentration of the active species on cyclic voltammetry has been investigated using three quasi-reference electrodes (QREs) (AgCl, Pt, and Pd) and three reference electrodes (REs) (Fc(+)/Fc/Pt, Ag(+)/Ag, and Cl(-)/AgCl/Ag). The results show that the internal resistance has to be taken dynamically into account during any cyclic voltammetry experiment. Quasi-reference electrodes can be used only for qualitative electrochemical studies. Reference electrodes based on Ag(+)/Ag or Fc(+)/Fc dissolved in an IL have a stable potential over 15 h and thus can be used to perform reliable electrochemical experiments in ionic liquids and to get quantitative information such as potentials.
authors.affiliation: University Grenoble-Alpes, LEPMI, F-38000 Grenoble, France.
authors.forename: C
authors.initials: C
authors.lastname: Bonnaud
authors.affiliation: University Grenoble-Alpes, LEPMI, F-38000 Grenoble, France and CNRS, LEPMI, F-38000 Grenoble, France.
authors.forename: I
authors.initials: I
authors.lastname: Billard
authors.affiliation: University Savoie, LEPMI, F-73000 Chambéry, France. nicolas.papaiconomou@lepmi.grenoble-inp.fr.
authors.forename: N
authors.initials: N
authors.lastname: Papaiconomou
authors.affiliation: University Grenoble-Alpes, LEPMI, F-38000 Grenoble, France and CNRS, LEPMI, F-38000 Grenoble, France.
authors.forename: E
authors.initials: E
authors.lastname: Chainet
authors.affiliation: University Grenoble-Alpes, LEPMI, F-38000 Grenoble, France.
authors.forename: J C
authors.initials: JC
authors.lastname: Leprêtre