EMIIm and EMIBeti on aluminum - anodic stability dependence on lithium salt and propylene carbonate

Abstract

The two anions bis(trifluoromethylsulfonyl)imide (Im) and bis(perfluoroethylsulfonyl)imide (Beti) display similar passivation on aluminum in solvent-free ionic liquids. The addition of 10% propylene carbonate to the ionic liquids EMIIm and EMIBeti (EMI: 1-ethyl-3-methyl imidazolium) introduces oxidative corrosion, with the Beti anion being 0.7 V more stable. The oxidation peaks are shifted to more positive potentials (ca. 0.1 V) with the addition of the lithium salt. The results from cyclic voltammetry and chronoamperometric experiments indicate propylene carbonate to be an active participant in the corrosion process on aluminum.