Electron Transfer Rates at Carbon Electrodes

15 Electron Transfer Rates at Carbon Electrodes Problem 

By altering the rate of electron transfer, the signals for the analytes can be made to occur closer to the formal potential for the reaction of interest, as the electrode kinetics become faster. If the voltammetric signal changes from electrochemically irreversible to reversible there will be a small increase in the peak current (see Problem 9.14) for linear sweep voltammetry but the most important consequence is the decreased overpotential at which current can be driven. Hence, less extreme potentials are required for the analysis. 

In general, optimisation of electrode materials for analytical tasks is desirable and worthwhile, while noting that sensitivity in terms of peak current (but not peak potential) in linear sweep voltammetry is essentially controlled by the rate of diffusion to the electrode and hence, provided a signal is seen at some potential, relatively insensitive to the electrode material. 

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