Global kinetic analysis of cyclic voltammograms at a spherical electrode

The global method for analyzing electrochemical processes controlled by diffusion and by the kinetics of heterogeneous electron transfer is redeveloped or application to electrodes haveing a spherical geometry. Heretofore, the method has been restricted to experiments in which plannar diffusion is the sole mode of transport to the electrode surface. The global method is based on a three-dimensional concept and has the advantage of using all of the data available from a voltammogram to measure the heterogeneous charge-transfer rate constant, the reversible halfwave potential, the diffusion coefficient, and the charge-transfer coefficient. Cyclic voltammetry of 2-methyl-2-nitropropane reduction at a mercury sphere is reported. The parameters measured by spherical global analysis are concordant and in excellent agreement with literature values.