Electrochemical behavior of ferrocene in aqueous and organic medium at glassy carbon electrode

Abstract

Many studies and analysis by electrochemical methods were effected on the oxido- reducing properties of ferrocene. In general, the cathodic behavior ferrocene usual in organic media such as dichorométhane, acetonitrile and DMF can be described by a reversible reduction in an electron, leading to ion Ferrocerium [1]. In the present work the oxidation of ferrocene, Fe(C5H5)2, to the ferrocenium cation, Fe(C5H5)2+, was examined in the solvents dichloromethane solution containing tetrabutylammonium tetrafluoroborate , and aqueous solution containing sulfuric acid using the technique of cyclic voltammetry[2,3], The results indicated that redox reactions of ferrocene/ ferricenium couple were a reversible process of diffusion-controlled single electron transfer in both studied solutions.The study was conducted on a fixed electrode of glassy carbon with different scanning speeds (0.05, 0.10, 0.30, 0.50 Vs-1) and we had a study on rotating electrode with different rotation speeds (400.600.800.1000 rpm), and we calculate some electrochemical parameters starting fromthe polarization curves of ferrocene, The parameters are : The anodic (Epa) and the cathodic (Epc) peak potentials, as well as the corresponding anodic (ipa) and cathodic (ipc) peak currents, and the half-wave potentials (E1/2) were obtained at different scan rates and different rotation speeds. The diffusion coefficients (D) have been calculated using the Randles-Sevcik equation [4].