4-tert-Butyl Pyridine Bond Site and Band Bending on TiO2(110)
Author
Summary, in English
In the present work, we study the bonding of 4-tert-butyl pyridine (4TBP) to the TiO2(110) surface using photoelectron spectroscopy (PES) and density functional theory (DFT) calculations. The results show that at low coverage, 4TBP adsorbs preferentially on oxygen vacancies. The calculated adsorption energy at the vacancies is 120 kJ/mol larger than that oil the five-fold-coordinated Ti4+ sites located in the rows on the TiO2 surface. The vacancy is "healed" by 4TBP, and the related gap state is strongly reduced through charge transfer into empty pi* orbitals on the pyridine ring. This leads to a change in surface band bending by 0.2 eV toward lower binding energies. The band bending does not change with further 4TBP deposition when saturating the surface to monolayer coverage, where the TiO2 surface is effectively protected against further adsorption by the dense 4TBP layer.
Department/s
Publishing year
2010
Language
English
Pages
2315-2320
Publication/Series
Journal of Physical Chemistry C
Volume
114
Issue
5
Document type
Journal article
Publisher
The American Chemical Society (ACS)
Topic
- Natural Sciences
- Physical Sciences
Status
Published
ISBN/ISSN/Other
- ISSN: 1932-7447