Interfacial electron-transfer and ligand-dissociation characteristics of layer-by-layer nanoarchitectures constructed from ruthenium cluster molecules

Interfacial electron-transfer properties and CO-dissociation reactions at redox-active multilayers which were prepared from trinuclear ruthenium cluster molecules have been examined by cyclic voltammetry. The series of multilayers (up to five layers) assembled on gold electrodes show a single-step, reversible, multi-electron redox processes whose redox potentials are finely tuned by the number of Ru ₃ components involved in the layers and are also affected by the nature of electrolyte anions. Electrochemical oxidation of the surface-confined CO-terminated multilayers (0.1 M HClO ₄ aq., 298 K) induces dissociation of CO from the top layer, resulting in the change of the cyclic voltammograms. The redox-induced CO-dissociation reaction for each of the multilayers obeys the first-order kinetics, in which the rate constants range in the order 10 ^-2 s ^-1 (298 K).