Use of the Furrocene Oxidation Process To Provide Both Reference Electrode Potential Calibration and a Simple Measurement (via Semiintegration) of the Uncompensated Resistance in Cyclic Voltammetric Studies in High-Resistance Organic Solvents

摘要

Because of its presumed ideal reversible behavior, the oxidation of ferrocene is widely used in cyclic voltammet-nc studies in highly resistive organic solvents as a means of reference electrode potential calibration. In this study, it is shown that a good estimate of the uncompensated resistance value, needed for reference potential correction and also frequently an input parameter in simulation of the theory, can be obtained simultaneously with the ferrocene reference potential measurement using a simple analysis based on the semlintegral. Application to cyclic voltammetric oxidation of ferrocene in dichioromethane (0.1 M NBu4PFs), under conditions where uncompen-sated resistances of —2.5 kf~ are encountered, is used to illustrate the fidelity of the semiintegral method of analy-sis. Inclusion of this estimated resistance value as the input parameter in a commercially available digital simu-lation package confirms that the oxidation of ferrocene in dichloromethane represents a close-to-ideal diffusion-controlled reversible process. However, use of the semi-integral method of data analysis also enables detection of subtle forms of nonideality encountered with the ferrocene oxidation process in other media where kinetically con-trolled adsorption of the ferricenium cation may occur.