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arXiv · 1804.07480

Charge Trapping at the Step Edges of TiO2 Anatase (101)

Martin Setvin·Xianfeng Hao·Benjamin Daniel·Jiri Pavelec·Zbynek Novotny·Gareth S. Parkinson·Michael Schmid·Georg Kresse·Cesare Franchini·Ulrike Diebold
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Abstract

A combination of Photoemission, Atomic Force and Scanning Tunneling Microscopy/Spectroscopy measurements shows that excess electrons in TiO2 anatase (101) surface are trapped at step edges. Consequently, steps act as preferred adsorption sites for O2. In Density Functional Theory calculations electrons localize at clean step edges, this tendency is enhanced by O vacancies and hydroxylation. The results show the importance of defects for the wide-ranging applications of titania.

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Martin Setvin, Xianfeng Hao, Benjamin Daniel, Jiri Pavelec, Zbynek Novotny, Gareth S. Parkinson, Michael Schmid, Georg Kresse, Cesare Franchini, Ulrike Diebold. 2018-04-20. Charge Trapping at the Step Edges of TiO2 Anatase (101). https://doi.org/10.1002/anie.201309796

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