Raman Spectra of a Cobalt Oxide-Molybdenum Oxide Supported Catalyst

The structures of cobalt-molybdenum supported catalysts are of great interest because of their use in the hydrodesulfurization of petroleum products and coal. While numerous infrared spectroscopic investigations of these systems have been made, vibrational data on the interaction between the active components of the catalyst and the support are difficult to obtain by infrared because of the intense absorption by the support material. A Raman investigation of a supported catalyst (10% MoO3 on γ-Al2O3) has been reported. No Raman scattering was observed and this was interpreted as evidence of the formation of a new compound which is Raman-inactive. This note describes the results of our preliminary investigation of the structure of a supported catalyst by Raman spectroscopy.