Three-channel transmission line impedance model for mesoscopic oxide electrodes functionalized with a conductive coating.

A three-channel transmission line (TL) impedance model is proposed to address the charge transport behavior of molecular functionalized mesoscopic oxide electrodes at different bias conditions. A full general solution of the three-channel TL for the system is provided in this paper. Selected experimental results of impedance spectroscopy of mesoscopic Al2O3 and TiO2 networks, covered with a monolayer of Ru complex cis-RuLL'(NCS)2 (L = 2,2'-bipyridyl-4,4'-dicarboxylic acid, L' = 4,4'-dinonyl-2,2'-bipyridyl) (Z907), are briefly discussed. It shows that the model constitutes a useful tool for characterizing nanoporous electrodes functionalized with organic conducting layers in the surface. The model makes it possible to determine the separate conductivity of substrate oxide and molecular layer, and interfacial charge transfer, in the functionalized nanostructured electrodes.