A surface spectroscopic study of metal-support interactions: model studies of copper on thin SiO, films
نویسندگان
چکیده
The metal-support interactions for a model silica-supported copper catalyst have been studied using temperature-programmed desorption, X-ray photoelectron and infrared reflection-absorption spectroscopies under ultrahigh vacuum conditions. The model catalyst support was prepared by synthesizing a thin SiO, film (_ 100 A) on a Mo(l10) surface. Copper was then evaporated onto the SiO, films. A small amount of copper f< 0.1 monolayer) is partially oxidized at the Cu/SiO, interface with the remainder forming 3D-clusters. The desorption energy of copper from the SiO, is found to depend markedly on copper coverage (cluster size).
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