Voltammetry of porous layers: Staircase vs analog voltammetry

• Linear and staircase voltammetry (LV, SV) at porous electrodes is investigated.
• Nernstian and Butler-Volmer electrode kinetics are considered.
• The choice of the sampling time in SV significantly influences the measurement.

The use of staircase ramps for cyclic voltammetry rather than true linear analog ramps can lead to significant misinterpretation of the signals recorded for the measurement of diffusional redox species with either reversible or irreversible electrode kinetics measured at electrodes modified with porous layers. Most notably a large perturbation of the expected peak current is apparent which can preclude the extraction of meaningful data, for example in respect of surface coverages or in the identification of electro-catalysis.