Rotating disk electrode: A re-examination of some kinetic criteria with a special reference to oxygen reduction

Abstract

Some of the well-known criteria for analysing rotating disk measurements have been examined. It has been shown that for reactions with complex mechanisms the number of electrons exchanged per reactant is a function of the potential of the electrode and cannot be evaluated theoretically in a simple manner. Also, it has been shown that none of the prescribed methods of obtaining the overall reaction order will give a proper answer unless the number of electrons is known a priori. This couling of the number of electrons exchanged and the overall reaction order is inherent in the rotating disk experiment. Therefore the use of the rotating disk in elucidating the overall kinetic parameters of the process is much more limited than previously thought.