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Substituted phenyl-modified glassy carbon electrodes were functionalized with metal/metal oxide/ metal hydroxide and inorganic compounds. More specifically, the glassy carbon electrodes were first functionalized with 4-sulfonate phenyl and N,N-diethylaniline groups by electrochemical reduction of the corresponding diazonium salt in nonaqueous media. Second, the functionalized electrodes were soaked in a solution containing the metallic ions and treated with a reductant (NaBH 4 ) in the case of the formation of the Ru-and Cu-based species or with redox species (Fe(II) or Fe(CN) 6 3-) in the case of Prussian Blue. The resulting Cu/Cu(OH) 2 and RuO 2 /Ru(OH) 2 -modified glassy carbon electrodes displayed electrochemical activity for selected reaction such as nitrate reduction and hydrogen peroxide oxidation, respectively. X-ray photoelectron spectroscopy was also used to confirm the presence of the metallic species and Prussian Blue at the electrode surfaces. The curve-fitting of the appropriate core level spectra was useful to distinguish between the oxide/hydroxide species and the metallic state. The atomic concentration of the metal-based species at the surface of the modified glassy carbon electrodes, estimated from the XPS data, ranged between 0.2 and 1 at. %, which corresponds to surface concentration of 0.55 × 10 -10 , 0.87 × 10 -10 , and 0.21 × 10 -10 mol/cm 2 for Cu, Ru, and Prussian Blue, respectively. These relatively low surface concentrations and the scanning electron micrographs of copper-or rutheniummodified glassy carbon electrode suggest that very small particles are present at the electrode surface. On the other hand, the presence of submicrometric particles was found to be evident for Prussian Blue formed on the modified surface. In the case of the copper-modified electrode, stripping voltammetry was used to estimate the amount of metallic copper, which was found to be in reasonably good agreement with the XPS data.

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Electrochemical deposition of metals from the H 1 hexagonal phase of nonionic lyotropic liquid-crystalline phases has been shown to produce films which contain regular arrays of uniform pores whose dimensions are determined by those of the micelles in the lyotropic phase used as the template. In this paper we report results for a study of the deposition of one H 1 -e metal film on top of another. Using H 1 -e films of palladium and rhodium as a model system we show, using electrochemical measurements, that the surface of the pores of the inner metal film are not blocked by deposition of an overlayer of the second mesoporous metal. By studying the evolution of the voltammetry of the mesoporous metallic bilayers as the surfactant is leached out of the pores over time, we conclude that the pores in the outer H 1 -e metal film connect to those in the inner layer so that we have a hexagonal array of continuous pores running though both metal layers in the structure.

Studies of the hydrogen region of nanostructured H 1 -e Pd films in 1 M sulfuric acid in the presence of crystal violet, or when small amounts of Pt are deposited on to the surface, show that the adsorption of hydrogen onto the metal surface is suppressed but that at the same time the kinetics of absorption of hydrogen into the Pd to form the b-hydride are significantly enhanced suggesting that the strongly adsorbed hydrogen on the Pd surface acts as a blocking layer for absorption of hydrogen into the Pd lattice.