Electrodes shapes and sizes

The ratios given in Eq. (4.66) are only dependent on the electrode shape and size but not on parameters related to the electrode reaction, like the number of transferred electrons, the initial concentration of oxidized species, or the diffusion coefficient D. For fixed time and size, the values of f or Qf2 are characteristic for a simple charge transfer (see Fig. 4.4 for the plot of Qf2 calculated at time (ti + T2) for planar, spherical, and disc electrodes) and, as a consequence, deviations from this value are indicative of the presence of lateral processes (chemical instabilities, adsorption, non-idealities, etc.) [4, 32]. Additionally, for nonplanar electrodes, these values allow to the estimation of the electrode radius when simple electrode processes are considered. 

The peak height of the SWV net current increases in all the cases with the square wave amplitude until it reaches a constant value (plateau) for sw > lOOmV. This value depends on the electrode shape and size and also on the catalytic rate constants. Under steady-state conditions, the plateau current at microspheres and microdiscs is given by... 

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