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Two series of ruthenium nanoparticles stabilized either by a polymer (polyvinylpyrrolidone; Ru/PVP) or a ligand (bisdiphenylphosphinobutane; Ru/dppb) were reacted with tributyltin hydride [(n-C4H9)3SnH] leading to tin-decorated ruthenium nanoparticles, Ru/PVP/Sn and Ru/dppb/Sn. The Sn/Ru molar ratio was varied in order to study the influence of the surface tin content on the properties of these new nanoparticles, by comparison with Ru/PVP and Ru/dppb. Besides HRTEM and WAXS analyses, spectroscopic techniques (IR, NMR and Mössbauer) combined with theoretical calculations and a simple catalytic test (styrene hydrogenation) allowed us to evidence the formation of μ(3)-bridging "SnR" groups on the ruthenium surface as well as to rationalize their influence on surface chemistry and catalytic activity.

Novel self-organized Ti₁/₂Sn₁/₂O₂ nanotubes can be produced by the electrochemical anodization of co-sputtered Ti-Sn thin-films. Combined X-ray photoelectron spectroscopy and (119)Sn Mössbauer spectroscopy of pristine samples evidenced the octahedral substitution of Sn(4+) for Ti(4+) in the TiO₂ structure. In addition to the improved lithium storage behaviour of the Ti₁/₂Sn₁/₂O₂ nanotubes, ex situ(119)Sn Mössbauer spectroscopy of cycled electrodes has sufficiently confirmed that no decomposition of the Ti₁/₂Sn₁/₂O₂ structure occurred, and that no Li-Sn phase was formed during the discharge, corroborating that the electrochemical reaction is due exclusively to Li(+) insertion into the Ti₁/₂Sn₁/₂O₂ nanotubes in the 1 ≤ U/V ≤ 2.6 voltage range.