To explore the influence of CeO2 doped TiO2 support on the dispersion, structure and acidic properties of molybdenum oxide species, an
investigationwas undertaken by using XRD,N2 adsorption, FTIR andUV-Vis diffuse reflectance techniques in addition to in situ FTIR-pyridine
study. In thiswork, theMoO3/TiO2 andMoO3/TiO2(CeO2) samples were prepared, at the 8 wt.%Moloading, by incipient wetness impregnation
method. The characterization results suggest that the Mo state in the calcined (773 K) MoO3/TiO2 sample is in X-ray amorphous character
and exhibit reasonably higher specific surface area (319m2 g−1) than that of MoO3/TiO2(CeO2) (273m2 g−1). The former support also
accommodates a sub-monolayer equivalent of MoO3 (8 wt.%) in a highly dispersed state. The UV-Vis spectra indicated that the dispersed Mo
in the MoO3/TiO2 sample is in tetrahedral coordination where it is in octahedral coordination on the MoO3/TiO2(CeO2) sample that showed
discrete amounts of bulkMoO3 species. Itwas revealed also that the presence of Ce retarded the strong association rendered between molybdena
and titania and thus, an over-layer of MoO3 was detected; as indicated by IR spectroscopy (1067 cm−1), paralleled with an appearance of high
intense and sharp XRD lines of TiO2 proposing sintering of the support. The latter result brings up activation of the TiO2 anatase as discrete
phase in MoO3/TiO2 (CeO2) as detected from UV-Vis; 380–400 nm. In situ FTIR spectra of pyridine adsorbed on the samples have revealed the
following results (i) all the samples exhibit Lewis and Bronsted acid sites (ii) the TiMo and TiCeMo samples exhibit higher Bronsted acidity
(1645–1636 and 1543 cm−1) than that of TiCe and rather presented basic sites similar to those offered by TiCe but of lower concentration.
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