THEORY AND EXPERIMENT FOR THE COLLECTOR-GENERATOR TRIPLE-BAND ELECTRODE

The currents obtained at a triple-band electrode with a central generator and flanking collectors have been calculated by digital simulation. To determine the current at steady state, a conformal map was used in which space is folded so that the geometry is similar to that of a thin-layer cell with opposing electrodes. This geometry makes the flux lines straighter and thus simplifies rapid, accurate calculations. If flux through the small gap between the collectors in the conformal space is ignored, a condition that is true at steady state, the current is shown to approach that of a thin-layer cell with continuous, opposing electrodes. At infinite times, the collection efficiency will be one and the inverse amplification factor (defined as the current at a single band divided by the generator current) approaches zero. To evaluate the current for experimentally achievable time scales, a different conformal map was used for the simulation. In this case, space was folded on either side of the generator, resulting in a three-sided geometry. Experimental data for the oxidation of ferrocene in acetonitrile are in good agreement with the simulated results. Comparison of the results reported here with prior work on the double- and single-band geometries shows advantages in the present case with respect to the time needed to achieve pseudo steady state.