The adsorption and surface reactions of free gas phase methyl radicals on oxygen-modified Mo(100) have been studied using a combination of temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS). Methyl radicals were found to adsorb on the surface at room temperature. Upon heating the surface methyl groups decompose to form surface hydrogen. The surface hydrogen hydrogenates the remaining intact methyl groups leading to methane which desorbs from the surface. The carbon produced by dehydrogenation combines with surface oxygen to yield CO. Comparison of the surface chemistry and the measured C(1s) binding energy with surface methoxy and with CH3 bonded to metal surfaces indicates that the methyl groups are primarily bonded to surface metal atoms to form a metal alkyl rather than to surface oxygen.
ASJC Scopus subject areas
- Colloid and Surface Chemistry