Multiple small potential steps at a rotating disk electrode and applications

A method of multiple small potential steps was applied to obtain current-potential curves at a rotating disk electrode (RDE), which is more accurate than the classical potential scan RDE method. Several basic benefits of the new RDE method were summarized, including reducing charging current, removing adsorption current, identifying kinetic current and separating kinetic and diffusion reactions. The practical application of this new method is to study high surface area powder catalysts for fuel cell research. An example of using this new method was demonstrated by measuring the current potential curves of catalytic oxygen reduction on heat-treated metalloporphyrins coated graphite rotating disk electrode. A successful kinetic analysis of catalytic oxygen reduction at the powder catalyst coated electrode was achieved. (C) 2000 Elsevier Science Ltd. All rights reserved.