Cyclic voltammetry in weakly supported media: The reduction of the cobaltocenium cation in acetonitrile – Comparison between theory and experiment

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Vol. 650; no. 1; pp. 135 - 142
• Main Authors: Limon-Petersen, Juan G., Dickinson, Edmund J.F., Belding, Stephen R., Rees, Neil V., Compton, Richard G.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.12.2010; Elsevier
• Subjects: Chemistry; Cobaltocenium; Electrochemistry; Exact sciences and technology; General and physical chemistry; Kinetics and mechanism of reactions; Migration; Nernst–Planck–Poisson equations; Ohmic drop; Supporting electrolyte; Weakly supported voltammetry; Weakly supported voltammetry; Supporting electrolyte; Nernst–Planck–Poisson equations; Ohmic drop; Migration; Cobaltocenium; Cationic complex; Cobalt Complexes; Voltage fall; Metallocene; Electrodes; Transport process; Chemical reduction; Cyclic voltammetry; Cobalt Organic compounds; Nernst-Planck-Poisson equations; Electrochemical reaction; Theoretical study; Poisson equation; Transition metal Complexes; Heavy metal; Hemispherical configuration; Electrolyte; Acetonitrile; Cations; Mercury; Comparative study
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/j.jelechem.2010.08.011

Experimental cyclic voltammetry at a hemispherical mercury microelectrode in acetonitrile solution, containing 3 mM cobaltocenium hexafluorophosphate and different concentrations of supporting electrolyte, is compared with theoretical simulations using the Nernst–Planck–Poisson system of equations, without the assumption of electroneutrality, and is found in to be in good agreement. Deviations from diffusion-only theory are analyzed in terms of migration and potential drop in the solution as a function of the concentration of supporting electrolyte. We are unaware of previous reports in which non-steady-state cyclic voltammetry without supporting electrolyte has been quantitatively and fully simulated, so this work opens up a new area for voltammetry.