Structural ordering transitions in ionic liquids mixtures

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Costa, R (Author) FCUP; Carlos M Pereira (Author) FCUP; Silva, F (Author) FCUP

Journal

Title: Electrochemistry Communications

Vol. 57

Pages: 10-13

ISSN: 1388-2481

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 21 Citations

Scopus - 22 Citations

Other information

Authenticus ID: P-00G-4NH

DOI: 10.1016/j.elecom.2015.04.012

Abstract (EN): Differential capacitance curves for the electrical double layer (EDL) of mixtures of imidazolium-based ionic liquids (ILs) with a common cation (1-ethyl-3-methylimidazolium, [C2MIM](+)) and two different anions (bis(trifuoromethylsulfonyl)imide, [Tf2N](-)) and tris(pentafluoroethyl)trifluorophosphate [FAP](-)) were obtained. Sharp peaks in the differential capacitance curves were observed for a small range of mixtures compositions at positive charge densities. The appearance and position on the potential scale of the peaks were found to be dependent on the mixture composition and temperature. The occurrence of these phenomena is interpreted as corresponding to an abrupt change in the EDL structure arrangement as a result of a complex interplay of electrostatic interactions and steric effects. The use of the non-structured mercury electrode allowed to decouple the eventual potential induced restructuring occurring at the double layer from the well-known surface reconstruction effects often reported for ionic liquids in contact with single crystal face electrodes.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 4