FACTORS DETERMINING THE SELECTIVE - EXPOSURE OF (010) PLANE OF V2O5 CATALYSTS SUPPORTED ON VARIOUS TIO2

V2O5 supported on various TiO2 including anatase, rutile and mixtures of both have been investigated with various physicochemical measurements such as BET, NH3-TPD, NARP, XRD and so on, and the effect of the crystal phase of the TiO2 support on the structure of the supported V2O5 was discussed. It has been found that the V=O species on the (010) plane of V2O5 on the TiO2 supports with large BET surface area are selectively exposed to the surface, though different crystal phases of TiO2 result in different characteristics of exposure of the (010) plane. Anatase gives the maximum exposure of the surface V=O species at significantly lower surface concentration of V2O5 than that for rutile. For the mixture of both, two maxima are obtained at the surface concentration of V2O5 corresponding to those for anatase and rutile respectively. The chemical activity of the TiO2 surface also seems to have an effect on the exposure of the (010) plane. That is, the higher surface area and the stronger acidic property resulted in the higher exposure of the (010) plane.