Direct correlation of the dispersion and structure in vanadium oxide supported on silica SBA-15
نویسنده
چکیده
Raman, UV-Vis and X-ray photoelectron spectroscopy were combined in one experimental setup to directly study the interplay between structure and dispersion of SBA-15 supported vanadium oxide during dehydration. The fully hydrated catalyst is slightly reduced but consists mainly of V species with pseudo-octahedral V coordination strongly resembling the xerogel V2O5·1.2H2O. After dehydration a highly dispersed surface anadium oxide species with tetrahedrally coordinated vanadium and significantly smaller ensemble size is formed. v
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