Location and activity of VOx species on TiO2 particles for NH3-SCR catalysis

NH3-SCR activity dependence of VOx-TiO2 catalyst on V loading. Dispersion of VOx species and their evolution on anatase crystal have been proposed based on the different characterization results. Monomeric VOx species do not have considerable catalytic activity, formation of oligomeric VOx species in medium coverages boost the NH3-SCR activity which is proportional to square of V loadings suggesting the bridged V-O-V as active species. Bulk species in high loading do not change the activity.