Radical species in modified electrodes

Abstract

Electrochemical e.s.r. spectroscopy can be used to study radical species in the coats of modified electrodes. A semi-annular electrode, which is part of the wall of a tube, can be placed in the centre of an e.s.r cavity with the electrolyte solution flowing past the electrode under conditions of laminar flow. This arrangement allows the system to be studied in the steady state. We have investigated three types of modified electrode: poly(nitrostyrene), poly(vinylanthraquinone) and poly(pyrrole). Good agreement is found between the charge injected into the coat and the number of spins observed. The kinetics of charge transfer within the coat have been investigated using transient studies. In the case of poly(pyrrole), which is an organic conductor, the line shape is Dysonian.