Methanol Adsorption and Decomposition on Clean and Oxidized Palladium (111).

Abstract : The interaction of methanol with Pd(111) has been studied using high resolution electron energy loss spectroscopy (HREELS). We find both a chemisorbed and a physisorbed phase on the surface at 140K. Desorption of the physisorbed phase occurs by 160K and approximately 90% of the chemisorbed layer desorbs by 300K. Exposure to methanol at 300K causes dissociation of chemisorbed CO. Decomposition of chemisorbed methanol to a methoxy species occurs near 200K in the presence of a preadsorbed p(2x2) oxygen layer whereas no methoxy is detected on the clean surface.