Study of a catalytic mechanism in double potential step techniques at spherical electrodes

Abstract

An analytical complete solution corresponding to the double potential step problem for the catalytic mechanism at spherical electrodes is presented. This solution is applicable to double potential step chronoamperometry, differential normal pulse voltammetry (DNPV), differential pulse voltammetry (DPV) and reverse pulse voltammetry (RPV). The effects of the sphericity of the electrode on the I/t and I/E responses are analysed. The equations deduced in this paper allow us to calculate smaller rate constant values than those that can be calculated by using microelectrodes when only steady state is considered. Methods for calculating kinetic and thermodynamic parameters for the catalytic mechanism in all the above mentioned techniques are proposed and applied to the system Ti (IV) oxalate complex in the presence of hydroxylamine at spherical electrodes of different radii.