Bridging Hydroxyls on Anatase TiO₂(101) by Water Dissociation in Oxygen Vacancies

Abstract

Titanium dioxide is a promising candidate for photocatalytic H₂ fuel production, and understanding water splitting on TiO₂ surfaces is vital toward explaining and improving the generation of H₂. In this work, we electron irradiate anatase TiO₂(101) at room temperature to create metastable surface oxygen vacancies in order to investigate their ability to dissociate H₂O. Our scanning tunneling microscopy investigations suggest that the surface oxygen vacancies can dissociate H₂O by forming bridging OH species. This claim is supported by theoretical calculations from the literature and our previously published spectroscopic measurements.