Fourier-transform infrared investigation of structures of vanadium oxide on various supports

Abstract

Surface structures of vanadium oxides supported on various metal oxides (titania, alumina, zirconia and silica gel) formed by wet impregnation and by gas-phase preparation have been studied by Fourier-transform infrared spectroscopy. The V content ranged from 1.4 to 12 wt %. The application of band-shape analysis to the severely overlapped and weak bands using a small computer system has provided quantitative information for the surface vanadates. The surface vanadium oxides on titania are composed of three species. On catalysts prepared by the gas-phase method a new phase of vanadate is observed in i.r. spectra. The surface vanadates vary with the preparation methods as well as the repeat time of VOCl₃ circulation.