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Electrochemical simulation is used to validate the geometry of commercially manufactured interdigitated array electrodes intended for use in generator–collector experiments, consisting of two interlocked arrays of band electrodes. A working surface is generated showing peak current as a function of scan rate and the inter electrode distance when cyclic voltammetry is performed at a single array of band electrodes. This working curve is then used to establish accurate electrode widths and inter-electrode distances of an interdigitated band array using a fully supported aqueous solution of ruthenium hexamine trichloride as a test system by running voltammetry at one of the two arrays at a time. Both arrays are then used at the same time to perform cyclic voltammetry to validate the established electrode geometries of 9.9 and 10.7 μ m for the electrode widths in the two arrays, and 10.5 μ m for the distance between adjacent electrodes. Cyclic voltammetry in generator–collector mode is then carried out, and these parameters used to successfully simulate the experimental data. The level of precision determined is essential for the quantitative interpretation of generator–collector measurements using interdigitated electrodes.

Two types of generator–collector electrode systems, (i) a gold–gold interdigitated microband array and (ii) a gold–gold dual-plate microtrench, are compared for nitrobenzene electroanalysis in aerated aqueous 0.1 M NaOH. The complexity of the nitrobenzene reduction in conjunction with the presence of ambient levels of oxygen in the analysis solution provide a challenging problem in which feedback-amplified generator–collector steady state currents provide the analytical signal. In contrast to the more openly accessible geometry of the interdigitated array electrode, where the voltammetric response for nitrobenzene is less well-defined and signals drift, the voltammetric response for the cavity-like microtrench electrode is stable and readily detectable at 1 μM level. Both types of electrode show oxygen-enhanced low concentration collector current responses due to additional feedback via reaction intermediates. The observations are rationalised in terms of a “cavity transport coefficient” which is beneficial in the dual-plate microtrench, where oxygen interference effects are suppressed and the analytical signal is amplified and stabilised.

The oxidation of potassium ferrocyanide, K4Fe (CN)6, in aqueous solution under fully supported conditions is carried out at interdigitated band and ring electrode arrays, and compared to theoretical models developed to simulate the processes. Simulated data is found to fit well with experimental results using literature values of diffusion coefficients for Fe ( CN ) 6 4 - and Fe ( CN ) 6 3 - . The theoretical models are used to compare responses from interdigitated band and ring arrays, and the size of ring array required to approximate the response to a linear band array is investigated. An equation is developed for the radius of ring required for a pair of electrodes in a ring array to give a result with 5% of a pair of electrodes in a band array. This equation is found to be independent of the scan rate used over six orders of magnitude.