Membrane voltammetry: the metal/electrolyte interface

Abstract

A straightforward method to generate ensembles of microelectrodes, using a commercial membrane material is reported. Quantitative analysis of the oxidative currents flowing for a solution phase redox probe (in voltammetric and chronoamperometric experiments) shows that a recessed microelectrode model describes transport to the individual elements of the ensemble. Treatment of the recessed electrode geometry in terms of an equivalent inlaid microelectrode geometry is described. This approximation allows the voltage sweep rate dependence of the voltammetric currents and the standard electron transfer rate constant of the redox probe to be obtained using existing theory. Furthermore, we propose that membrane voltammetry may be a useful tool for the characterisation of porous materials, given the inherent sensitivity of electrochemical experiments to mass transport parameters.