Theory and experiment for the collector-generator triple-band electrode

Abstract

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 Knee stralghter 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 doubleand single-band geometries shows advantages In the present case with respect to the time needed to achieve pseudo steady state.

Theoretical treatment and computer simulation of microelectrode arrays

“…By digital simulation, they demonstrated the preponderate influence of the gap size on the collection efficiency. Conformal maps for modelling the collector-generator behavior as a function of the widthto-gap ratio for a double [2] and a triple band configuration [3] have shown a good agreement between models and experimental data. Later, the application-specific modelling based on conformal mapping was successfully adopted for simulating the current distribution at dual microband electrodes and their efficiency in electrochemical titrations [4,5].…”

Using electrochemical coupling between parallel microbands for in situ monitoring of flow rates in microfluidic channels

“…Theories and numerical simulations have been developed by different groups to fulfil this objective [1,2,4,[35][36][37][38][39][40][41][42][43][44]. The influence of experimental parameters related to the geometric design of the channel-electrode assembly as well as to the flow rate on the electrochemical signal could thus be predicted and optimized.…”

Towards paired and coupled electrode reactions for clean organic microreactor electrosyntheses

“…Each electrode has a band geometry with a bandwidth of typically 0.1-100 lm and a gap between electrodes of similar size. For the interdigitated band electrode of equally sized electrodes and gaps, the steady-state feedback current has been determined [31,32] and the approximate (steady state) diffusion layer thickness d can be equated in good approximation to the width of the inter-electrode gap between the electrodes, w (Equation 1).…”