Theory of stationary current-potential curves at microdisk electrodes for quasi-reversible and totally irreversible electrode reactions

Abstract

An analytical equation for stationary current-potential curves at microdisk electrodes was derived by the Wiener-Hopf method when the electrode reaction is quasi-reversible and totally irreversible. The current-potential curve is a function of the kinetic parameter, ▪, where ▪ and ▪ are the forward and backward reaction rate constants, respectively; a is the radius of the electrode and D is the diffusion coefficient. The equation consisted of a set of simultaneous equations and was solved numerically. A technique of evaluating the kinetic parameters from experimental current-potential curves is presented which is similar to the method of a polarographic log-plot. The theoretical current-potential curves were compared with that at a hemispherical electrode.