The influence of nitrogen doping on the electronic structure of the valence and conduction band in TiO2. (13th December 2018)

• Record Type: Journal Article
• Authors: Wojtaszek, Klaudia; Wach, Anna; Czapla-Masztafiak, Joanna; Tyrala, Krzysztof; Sá, Jacinto; Yıldız Özer, Lütfiye; Garlisi, Corrado; Palmisano, Giovanni; Szlachetko, Jakub
• Is Part Of: Journal of synchrotron radiation. Volume 26:Part 1(2019)
• Page Start: 145
• Page End: 151
• Publication Date: 2018-12-13
• Subjects: X‐ray emission spectroscopy -- X‐ray absorption spectroscopy -- electronic structure analysis -- TiO2 doping; Synchrotron radiation -- Periodicals; Free electron lasers -- Periodicals; 539.73505
• DOI: 10.1107/S1600577518016685
• Languages: English
• ISSNs: 0909-0495

Abstract

Abstract : The modification of the titanium dioxide valence band by insertion of N p ‐states is observed with simultaneous dumping of unoccupied d ‐orbitals of titanium. Abstract : X‐ray emission spectroscopy (XES) and X‐ray absorption spectroscopy (XAS) provide a unique opportunity to probe both the highest occupied and the lowest unoccupied states in matter with bulk sensitivity. In this work, a combination of valence‐to‐core XES and pre‐edge XAS techniques are used to determine changes induced in the electronic structure of titanium dioxide doped with nitrogen atoms. Based on the experimental data it is shown that N‐doping leads to incorporation of the p ‐states on the occupied electronic site. For the conduction band, a decrease in population of the lowest unoccupied d ‐localized orbitals with respect to the d ‐delocalized orbitals is observed. As confirmed by theoretical calculations, the N p ‐states in TiO2 structure are characterized by higher binding energy than the O p ‐states which gives a smaller value of the band‐gap energy for the doped material.