Surface Structures of Supported Molybdenum Oxide Catalysts: Characterization by Raman and Mo L3-Edge XANES

Corrosion Inhibition of Aluminum Alloy 2024-T3 by Sodium Molybdate

“…42,44 Similar results were obtained when characterizing S-phase particles on the surface. All the major bands of the spectra concur with the existence of Mo 7 42 It should be noted that the major Raman band for MoO 3 (996 cm −1 ) 43,44 was not detected in the above spectra. Characterization of the Fe-containing intermetallic particles (Fe-IMC) revealed the existence of yet another species on the surface.…”

“…According to Hu et al, 42 the structure of surface molybdenum oxides present on Al 2 O 3 under ambient conditions consists of polymeric species (Mo 7 O 24 6− and Mo 8 O 26 4− ) at high Mo loadings. In addition, Spevack et al found evidence of multivalent (Mo(IV), Mo(V), and Mo(VI)) species within molybdenum oxide films supported on alumina and graphite.…”

A Mo–K Edge XAFS Study of the Metal Sulfide-Support Interaction in (Co)Mo Supported Alumina and Titania Catalysts

“…The height of the preedge peak might additionally point to partial incorporation of Mo in tetrahedral molybdenum oxide species, especially for the Al 2 O 3 samples, although this amount will be very small. The structure of molybdenum oxide on several oxidic supports has been extensively described by several authors; see, for example, Wachs et al (46)(47) dispersion slightly increases upon calcining. In case of TiO 2 the opposite happens and the molybdenum oxide particles sinter when calcined at 450…”

Spectroscopic Studies on ZrO2Modified with MoO3and Activity for Acid Catalysis

“…29,30 Raman bands between 910 and 980 cm −1 are usually attributed to the Mo=O vibration of Mo species in either octahedral or tetrahedral environment. 31 Generally, monomolybdate or tetrahedral molybdenum oxygen species have been assigned for low MoO3 loading samples, 29,31,32 and two-dimensional polymolybdates or octahedral molybdenum-oxygen species with characteristic band around 950-980 cm −1 , for high MoO3 loading samples. 29,31,32 Therefore, the broad band observed in the 900-1000 cm , assigned to Mo=O vibrations 29,30 in two dimensional polymolybdate, were observed similarly to those of Figure 1.…”