Ferrocene as a Reference Redox Couple for Aprotic Ionic Liquids

✍ Scribed by Andrzej Lewandowski; Lukasz Waligora; Maciej Galinski

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 235 KB
• Volume: 21
• Category: Article
• ISSN: 1040-0397
• DOI: 10.1002/elan.200904669

✦ Synopsis

Abstract

The electrochemical behavior of ferrocene has been studied in a number of room temperature ionic liquids. Diffusion‐controlled, well‐defined anodic and cathodic peaks were found for the Fc/Fc^+^ (ferrocene/ferrocenium) oxidation/reduction on the gold electrode. Ohmic resistance R between working and auxiliary electrodes was deduced from impedance measurements. Cyclic voltammograms were corrected for the base line current as well as for the ohmic drop (IR). The formal potential 1/2(E~pa~+E~pc~) for ferrocene reduction/oxidation in aprotic ionic liquids tested is within a relatively narrow range and may be approximated by the value of 0.527±0.018 V (against the cryptate Ag/Ag^+^222 in acetonitrile reference). Ferrocene diffusion coefficients, calculated from the peak current dependence on the sweep rate, were of the order of 10^−7^ cm^2^ s^−1^.