On the use of digital staircase ramps for linear sweep voltammetry at microdisc electrodes: Large step potentials significantly broaden and shift voltammetric peaks

Cyclic voltammetry is widely used to investigate redox systems and is especially useful for determining electrode kinetic data. Experiments to obtain this data typically involve measuring the peak-to-peak separation as a function of voltage scan rate and applying appropriate theory. Experimental data are almost invariably measured using a digital potentiostat and as such the applied potential will have been varied in a series of discrete steps separated by a value Delta E-step. In this work, we calculate the error introduced by approximating a potential ramp as a staircase and consider how this insight may be used to ensure that electrode kinetic parameters extracted from experimental voltammetry so measured are accurate. (C) 2008 Elsevier B.V. All rights reserved.