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The Prato reaction was applied for the covalent introduction of a variety of organic moieties onto carbon-encapsulated iron nanoparticles. The developed method is versatile and employs a broad range of commercially available reactants, including both aromatic and aliphatic aldehydes. The reported functionalization route provides high functionalization yields (ca. 12-21 wt%).

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Electrocatalytic activity of Pt and bimetallic PtRu nanoparticles (both Vulcan supported and unsupported) toward electrooxidation of dimethyl ether (DME), a potential small organic molecule fuel, in an acid medium (0.5 mol dm−3 H2SO4) has been significantly enhanced by dispersing them over a thin film of zirconia (ZrO2). The enhancement effects concern increases of the DME electrocatalytic current densities recorded under both cyclic voltammetric and chronoamperometric conditions. Similar effects have been observed for the oxidation of methanol. Regarding the dissimilar DME electrooxidation mechanisms at Pt and PtRu catalytic centers, the activating capabilities of zirconia seem to originate from the high population of reactive –OH groups favoring mobility of protons and the capability of inducing the oxidative removal of poisoning (CO-type) intermediates both at platinum and ruthenium catalytic sites. In the presence of the zirconia matrix, the onset potential for the oxidation of DME (particularly at PtRu) is shifted more than 50 mV toward less positive potentials. Mutual metal-support interactions are also postulated.

Electrochemical deposition of crosslinked oxo-cyanoruthenate, Ru-O/CN-O, from a mixture of RuCl3 and K4Ru(CN)6 is known to yield a film on glassy carbon that promotes oxidations by a combination of electron and oxygen transfer. Layer-by-layer (LbL) deposition of this species and of a film formed by cycling of the electrode potential in a ZrO2 solution systematically increases the number of catalytically active sites of the Ru-O/CN-O on the electrode. The evaluation of the electrocatalytic activity was by cyclic voltammetric oxidation of cysteine at pH 2. Plots of the anodic peak current vs. the square root of scan rate were indicative of linear diffusion control of this oxidation, even in the absence of ZrO2, but the slopes of these linear plots increased with bilayer number, n, of (ZrO2 | Ru-O/CN-O)n. The latter observation is hypothesized to be due to an increased number of active sites for a given geometric electrode area, but proof required further study. To optimize utilization of the catalyst and to provide a size-exclusion characteristic to the electrode, the study was extended to LbL deposition of the composite in 50-nm pores of an organically modified silica film deposited by electrochemically assisted sol-gel processing using surface-bound poly(styrene sulfonate) nanospheres as a templating agent.