Structural Characterization of Molybdenum Oxide Supported on

No new bands appeared after treating this mixture at 673 K for 1 h in 20% ..... Raman spectroscopy even at very low Mo contents (0.1 wt %) on α-Al2O3...
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J. Phys. Chem. B 2000, 104, 10059-10068

10059

Structural Characterization of Molybdenum Oxide Supported on Zirconia Shuibo Xie, Kaidong Chen, Alexis T. Bell,* and Enrique Iglesia* Chemical and Materials Sciences DiVisions, E. O. Lawrence Berkeley National Laboratory, and Department of Chemical Engineering, UniVersity of California, Berkeley, California 94720-1462 ReceiVed: July 6, 2000

X-ray diffraction and X-ray absorption and Raman spectroscopies were used to determine the structure of dispersed and crystalline structures in MoOx/ZrO2 catalysts useful in the oxidative dehydrogenation of alkanes. The MoOx surface density on ZrO2 was varied over a wide range (0.35-50 Mo/nm2) by changing the Mo content (1-44 wt % MoO3) and the treatment temperature (393-973 K). Raman spectra showed that MoOx/ ZrO2 samples with low surface density (