DETERMINATION OF THE MO SURFACE ENVIRONMENT OF MO/TIO2 CATALYSTS BY EXAFS, XANES AND PCA

The local structure of oxidic Mo/TiO2 catalysts (0.5 to 13.5 wt.% Mo) has been studied using EXAFS and XANES. Both EXAFS and XANES results suggest that the Mo surface phase is octahedrally coordinated for all Mo loadings. The EXAFS results were also examined using principal component analysis (PCA) to determine the number of Mo species present on the Mo/TiO2 catalysts. Results from PCA of the Mo EXAFS spectra suggested the presence of three Mo species: two surface species and bulk MoO3.