Solid State NMR studies on the mechanisms of immobilized organic-inorganic metal containing heterogeneous catalysts

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Multi nuclear solid state NMR and other physico-chemical techniques are employed for the study of immobilized catalysts, metal-clusters, metal-nanoparticles and their interactions with substrates. The immobilized catalysts are made by covalently binding metal-containing catalysts to the surface of nano-structured silica materials with different morphologies(porous or nanoparticles) via organic linkers. The structure of the immobilized catalysts on the support material, its interactions with substrates and the influence of macroscopic parameters such as temperature on its properties are investigated. The catalytic activity of the catalysts is tested by model reactions, in particular hydrogenations. Initially simple reactions like the isotope scrambling of hydrogen or the hydrogenation of ethylene as model reactions for the catalysts are employed. To reveal effects of the size and morphology of the support, larger substrate molecules and enantio-selective immobilized catalysts are studied. In parallel to these studies we wish to continue our collaboration with the Chaudret and Poteau groups on the study of molecular hydrogen interacting with catalytically active transition metal compounds and nano-particles. Here we want to employ the 2H NMR data-base built in the first period for the study of hydrogen adsorbed on transition-metal nanoparticles (ruthenium, palladium, platinum). Finally we want to study the hydrogen dynamics of the H4Ru4(CO)12 cluster and reveal the nature of the dynamic process and its energetic parameters.