Synthesis, characterization and catalytic performance of Ni-V-O catalysts

Catalysts Ni3V2O8, Ni(2)V(2)O7, NiV2O6 were prepared and characterized by X-ray diffraction ( XRD), BET, H-2-TPR, XPS and conductivity measurement. Their catalytic performance for the oxidative dehydrogenation of propane to propene was investigated. The results show that the selectivities to propene were 69. 13%, 70. 21% and 64. 41% over p-type semiconductor Ni-3 V-2 O-8, Ni-2 V-2 O-7, and n-type NiV2O6 catalysts with 10% propane conversion, respectively. These results suggest that p-type semiconductor catalysts have a better catalytic performance than n-type ones, that C3H6 selectivity has a good correlation with the electrical conductivity and that selectivity depends on the existence of Ni3V2O8 or Ni2V2O7 phase. XPS results illustrate that high catalytic performance on p-type semiconductor Ni3V2O8 and Ni2V2O1 was related to the abundant oxygen species O- and V4+ existing over these catalysts.