Derivation of a general theory for reversible multistep electrode processes in voltammetry with constant potential at spherical electrodes

The rigorous theory for a reversible multistep electrode process in voltammetry with constant potential at spherical electrodes is derived. The expressions for the surface concentrations, the concentration profiles of species participating in the different steps and the current as a function of time have been deduced. These expressions are valid for any number of steps in which the initial species is oxidized/reduced, whatever the relative values of the formal potentials of the different steps and for any electrode radius value, including plane electrodes and ultra-microelectrodes.