Theory of a.c. voltammetry at a rotating disk electrode: Part II. Quasi-reversible and irreversible redox-electrode reactions

Abstract

Alternating current response at a rotating disk electrode to a small a.c. potential wave superimposed on the slowly changing d.c. potential is theoretically treated for an quasireversible and an irreversible redox-electrode process. Expressions for alternating current-d.c. potential curves are given for three types of a.c. signals, i.e., sinusoidal, rectangular and triangular waves. It is shown that the effect of the coupling of the diffusion layers due to hydrodynamics and a.c. polarization can be expressed in terms of a parameter which is defined by the ratio of the frequency of a.c. wave to that of the rotation of the electrode and Schmidt number.