[en] Reactivity of adsorbates with titania is typically influenced by the presence of surface oxygen vacancy defects. For alcohols, it is well-established that their dissociation on bridge-bonded oxygen vacancies (BBOV's) of a prototypical TiO₂(110) surface proceeds via heterolytic cleavage of the RO-H bond. The resulting intermediates are alkoxide (RO) that fills the vacancy and a proton that binds to a neighboring oxygen anion. Except for methoxide, these alkoxides dehydrate at elevated temperatures (well above 300 K) via β-hydride elimination to form alkenes.In some cases, the dehydration is accompanied by a minority dehydrogenation channel yielding aldehydes