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Updated: May 22, 2026

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
Intrinsic nature of the excess electron distribution at the TiO2(110) surface
P Krüger1, J Jupille, S Bourgeois
1ICB, UMR 6303 CNRS-Université de Bourgogne, BP 47870, F-21078 Dijon, France. pkruger@u-bourgogne.fr
Abstract:
The gap state that appears upon reduction of TiO2 plays a key role in many of titania's interesting properties but its origin and spatial localization have remained unclear. In the present work, the TiO2(110) surface is reduced in a chemically controlled way by sodium adsorption. By means of resonant photoelectron diffraction, excess electrons are shown to be distributed mainly on subsurface Ti sites strikingly similar to the defective TiO2(110) surface, while any significant contribution from interstitial Ti ions is discarded. In agreement with first principles calculations, these findings demonstrate that the distribution of the band gap charge is an intrinsic property of TiO2(110), independent of the way excess electrons are produced.
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