Cyclic voltammetry wave-shaped steady-state voltammograms

When cyclic voltammetry is performed with microelectrodes it is possible to record wave-shaped steady-state voltammograms at not too high scan rates, similar to dc polarograms. Ideally, there is almost no hysteresis and the half-wave potential is equal to the mid-peak potential of the cyclic voltammograms at macroelectrodes (see Chap. II. 1). 

Cyclic voltammetry is a method frequently used to measure 7s,i ni. Mediated bioelectrocatalysis yields cyclic voltammograms (CVs) of different shapes as illustrated in Fig. 2, depending on the measuring conditions [11]. Curve (a) is the wave for a reversible electrode reaction of an Mox/Mred redox couple. Bioelectrocatalysis mediated with the Mqx/ Mred redox couple produces a sigmoidal catalytic wave as curve (c) under the conditions [Mred] - M and [S] Ks. When [Mred] is increased to higher concentrations, an anodic peak of the diffusion current of Mred rnay be overlapped on the catalytic current as depicted by curve (d) the current, however, becomes steady state after appropriate periods... 

When microelectrodes are used instead of the normal-sized electrode in cyclic voltammetry experiments, voltammograms with the steady-state wave shape are obtained (Fig. 10.5.2). The half-wave potential, E1/2 is equal to the mid-peak potential of the cyclic voltammetric curve recorded using a large electrode. 

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