FT-IR spectroscopy is employed to investigate the methane dissociation and methane partial oxidation over the Rh/SiO 2 catalyst. When CH 4 is adsorbed onto the catalyst surface, it dissociates into adsorbed CH x (x=1~3) and atomic hydrogen on Rh surface. Atomic hydrogen can diffuse from Rh surface to SiO 2 surface where a proton exchange reaction of H with the surface Si-OH occurs, or it reacts with the lattice oxygen of SiO 2 to form new Si-OH