Channel electrode adsorbed species

One of the advantages of hydrodynamic electrodes over those employed in stationary solution is that both steady-state and time-dependent measurements can be made. Whilst, for the majority of applications, channel electrodes are operated under steady-state conditions, switching to the "time-dependent mode is often useful. Firstly, the sensitivity is enhanced (this is of particular benefit in analytical applications) and secondly, the concentration of species adsorbed or deposited on the electrode can be controlled. In systems in which the electrode is prone to fouling, for example, the time... 

The magnitude of the signal represents the total optical response of the system to the modulation frequency d>, while the phase represents the phase delay. Provided the phase delay across the solution band is constant (the species is in a homogeneous environment), the value of is measured for a solution species, and then the entire complex spectrum is rotated into the quadrature channel, as shown in Fig. 3.50. As a result, only the absorption due to surface species with different phase delays remains in the in-phase channel. This technique was used for disentangling strong bands due to the ferro/ferricyanide Faradaic species that were superimposed on weak bands of these species in the adsorbed state on a Pt electrode [263]. 

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