Dresden 2017 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 20: Solid-Liquid Interfaces: Reactions and Electrochemistry - Experiment I

O 20.6: Vortrag

Montag, 20. März 2017, 17:45–18:00, WIL B321

Model Studies on the Electrochemical Decomposition of BMP TFSI on Gold and Glassy Carbon Electrodes — •Dorothea Alwast¹, Johannes Schnaidt², Kurtus Hancock¹, and R. Jürgen Behm^1,2 — ¹Ulm University, Institute of Surface Chemistry and Catalysis, D-89069 Ulm, Germany — ²Helmholtz-Institute Ulm (HIU) Electrochemical Energy Storage, D-89081 Ulm, Germany

Ionic liquids (ILs) have shown promise as possible electrolytes for batteries. Therefore, the electrochemical stability of these ILs plays a key role for the use in batteries. In order to better understand the catalytic effect of different electrode materials on the electrochemical decomposition of ILs, we investigated the formation of volatile products of 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (BMP TFSI) formed during linear potential sweeps on polycrystalline Au and GC electrodes. For the online analysis of the volatile decomposition products we used a differential electrochemical mass spectrometry (DEMS) setup specifically designed for studying ILs. On both gold and glassy carbon electrodes decomposition products of the TFSI anion (m/z = 69, CF₃⁺; m/z = 64, SO₂⁺) are mainly detected at positive potentials, while decomposition products of both ions are formed at negative potentials. The similarities and differences in the products’ distribution on the two electrode materials and the implications of these findings on the mechanism of the IL’s electrochemical decomposition will be discussed.