Raman studies of supported V, Cr and Sb oxides and their mechanical mixture with α-Bi 2Mo 3O 12

Abstract

The interaction between V–Sb or V–Cr–Sb oxides and α-Bi 2Mo 3O 12 in mechanical mixtures during thermal treatments has been studied by laser Raman spectroscopy. Isolated V–Sb oxide and α–Bi 2Mo 3O 12 remain unchanged up to above 600°C. When mixed, V-related bands start to disappear and Bi–Mo-related bands widen already at 600°C indicating some kind of interaction between them. The presence of Cr 2O 3 in the mixture speed up this interaction, leading to the formation of a new Bi–Mo–V–O compound at temperatures below 600°C.