Reductive coupling desorption of methanol on reduced SrTiO₃(110)

Abstract

The adsorption and reaction of methanol with SrTiO₃(110) has been studied using temperature-programmed desorption and X-ray photoelectron spectroscopy. The main organic products are methane and ethane, though the exact ratio of these depends on sample history and defect levels in the surface and bulk. It is likely that the methanol dissociates to form adsorbed methyl groups associated with reduced Ti³⁺ and Ti²⁺ centres which were formed by Ar⁺ bombardment. We tentatively associate ethane formation with the latter sites and dialkyl formation, while methane production may be associated with the former sites and monoalkyl formation.

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