The voltammetric response of a conical electrode

Artjom V. Sokirko I, Keith B. Oldham x

Department of Chemistry, Trent University, Peterborough, Ont. K9J 7B8, Canada

Received 21 May 1996: revised 24 July 1996: accepted 6 August 1996

Abstract

A theoretical study has predicted the course of chronoamperometry following the imposition of a large potential step on an electrode in the shape of an infinite cone, under the usual diffusion-controlled conditions (with diffusivity D ). We show how the current density (at a distance r from the apex and at a time t after the step) depends on r2/Dt and on the semi-apical angle of the cone. The long-time version of this relationship predicts that a cone with a semi-apical angle of 54.74 will display the unique voltammetric property of independence from D. The short-time relationship throw light on the voltammetric behaviour of vertices in general. © 1997 Elsevier Science S.A.

Keywords: Voltammetry; Conical electrode; Chronoamperometry