An electron spectroscopic investigation of the interaction of methanol with polycrystalline aluminum

X-ray and ultraviolet photoelectron spectroscopic results are reported for the interaction of CH₃OH with clean polycrystalline Al in the temperature range 110–500 K. Methanol is moleculary chemisorbed at low exposure and low temperature (110 K) followed by condensation at higher exposure. Bonding mechanisms and geometries in the condensed and chemisorbed layers are discussed. The multilayers desorb beginning near 170 K and the chemisorbed layer is converted into a surface methoxide. Room temperature adsorption also leads to formation of the methoxide species which is stable to ～500 K, at which point it decomposes evolving CH₄ and leaves the surface oxidized.