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

Author(s)
Martin Setvin, Xianfeng Hao, Benjamin Daniel, Jiri Pavelec, Zbynek Novotny, Gareth S. Parkinson, Michael Schmid, Georg Kresse, Cesare Franchini, Ulrike Diebold
Abstract

A combination of photoemission, atomic force, and scanning tunneling microscopy/spectroscopy measurements shows that excess electrons in the TiO

2 anatase (101) surface are trapped at step edges. Consequently, steps act as preferred adsorption sites for O

2. 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. In step: Step edges on the TiO

2 anatase (101) surface act as exclusive charge trapping centers. While the electron trapping is not favorable at (101) terraces, it is possible at the steps. It results in a higher reactivity of the steps towards some adsorbates, as illustrated for the example of O

2 adsorption.

Organisation(s)
Computational Materials Physics
External organisation(s)
Czech Academy of Sciences, Technische Universität Wien
Journal
Angewandte Chemie (International Edition)
Volume
53
Pages
4714-4716
No. of pages
3
ISSN
1433-7851
DOI
https://doi.org/10.1002/anie.201309796
Publication date
04-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
103025 Quantum mechanics, 103036 Theoretical physics, 103015 Condensed matter, 103009 Solid state physics
Keywords
ASJC Scopus subject areas
General Chemistry, Catalysis
Portal url
https://ucrisportal.univie.ac.at/en/publications/64ba83d1-a573-42a9-9ab5-bda3972050fc