Electrochemical Behaviour Of Ferrocene/Ferricinium Redox System In Pure And CO2 Saturated [C6MIM][PF6]

Sebastien  Chanfreau; Liang Nian He; Bing Yu

Sebastien Chanfreau State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, People’s Republic of China
Liang Nian He State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, People’s Republic of China
Bing Yu State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, People’s Republic of China

Keywords: Ionic liquid, Ferrocene, Electroanalysis, Diffusion coefficient

Abstract

The electrochemical behaviour of ferrocene has been studied in green solvent combining pure ionic liquid and CO₂. Experimental results were achieved for the Fc/Fc⁺ (ferrocene/ferricinium ion) oxidation/reduction in pure and CO₂ saturated 1-hexyl-3-methylimidazolium hexafluorophosphate ([C₆MIM][PF₆]) over the temperature range from 298.15 K to 323.15 K. Peak shaped voltammograms were obtained and usual electrochemical parameters were calculated in order to classify electron process at the electrode. Diffusion coefficients of electroactive species were determined in the order of 10-11 m² s^-1 using the Randles–Ševcík relationship. Mass transport was also favoured by both increases in temperature and dilution of CO₂ in the media.

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