Surface studies of supported model catalysts

摘要: Metal particles grown by vapour deposition on clean and well-defined oxide surfaces are used as model catalysts. These new catalysts allow, unlike metal single crystals, a study of size support effects in heterogeneous catalysis. The structure, the electronic properties reactivity these supported have been studied, situ, large number surface science techniques. In order to get relevant information from those studies it is necessary control nucleation growth uniform collections particles. preparation conditions characterisation methods will be reviewed. Particles with shapes obtained epitaxial at high temperature ordered surfaces. small depend not only their but also shape. chemisorption strongly related structure interplay between local adsorption energy discussed for CO chemisorption. presence plays an important role particle morphology. Furthermore, can increase rate. intrinsic heterogeneity has taken into account understand detail catalytic reactions. reaction rate cannot considered average different crystalline facets present particle. Finally, we discuss possibility situ atomic level simple chemical reactions