TEMPLATE PREPARATION OF NANOELECTRODE ENSEMBLES - ACHIEVING THE PURE-RADIAL ELECTROCHEMICAL-RESPONSE LIMITING CASE

We have been investigating a new method for preparing ensembles of dis c-shaped nanoscopic electrodes. This method entails deposition of the electrode material into the pores of a nanoporous membrane. Nanoscopic wires of the electrode material, with monodisperse diameters, are obt ained in each pore. The ends of these nanowires (at one face of the me mbrane) define the ensemble of disc-shaped nanoelectrodes. We call thi s approach for preparing nanoelectrode ensembles (NEEs) the template m ethod. In all our prior investigations the electrode elements in the N EE were so close together that the diffusion layers at the elements ov erlapped. This is called the 'total-overlap' electrochemical-response limiting case. Here, we demonstrate (for the first time) that it is po ssible to use the template method to prepare NEEs with elements so wid ely spaced that the diffusion layers are completely isolated. The key to achieving this 'pure-radial' limiting case is obtaining template me mbranes with very low porosities.