PNNL

Abstract

We have performed a systematic study of the role of excess electrons resulting from points defects such as oxygen vacancies, bridging row hydroxyls, and interstitial Ti species in TiO2 on adsorbed surface species using density functional theory. Strong charge transfer to adsorbates affects significantly their binding and reactivity. Specifically we examined the adsorption and reactivity of O2 in detail. We also present a generalization of these findings for a variety of species by characterizing the Lewis acid/base properties of the surface/adsorbate complex: when the electronegativity of the adsorbate is greater than the surface electronegativity (or work function) charge transfer from the reduced surface to the absorbate occurs. This work was supported by the US Department of Energy, Office of Basic Energy Sciences, Chemical Sciences program. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.