Roles of vanadium substitution of monoclinic TeMo₅O₁₆ catalyst for propane selective oxidation

The vanadium-doped monoclinic TeMo₅O₁₆ catalysts were prepared and tested in the propane selective oxidation reaction. The doped catalysts showed high activity and high yield of propylene and acrolein. The catalysts were characterized by temperature-programmed surface reaction, Raman spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, H₂ temperature-programmed reduction, and O₂-thermogravity. The relationship between catalytic activity and catalyst properties on the surface and in the bulk was discussed. The results strongly suggested that the surface Mo-O bonds were changed by the V-doping. Thus the activity of surface redox sites was improved, and the amount of surface acid sites was increased, which promoted the activation and oxidation of propane. The bulk redox ability was further improved by a higher V-doping amount while the phase was unchanged basically.