Modification of TiO2(001) surface electronic structure by Au impurity investigated with density functional theory

Download

index.pdf

Date

2009-07-01

Author

METE, ERSEN
GÜLSEREN, Oğuz
Ellialtıoğlu, Süleyman Şinasi

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

188
views

88
downloads

We have used density functional theory calculations based on the projector augmented wave method to investigate the electronic structure of Au-incorporated anatase TiO2(001) surface. Due to the coordination with several level oxygens, Au atoms can be encapsulated inside TiO2 slab. Au is adsorbed over the surface Ti-O bond, so-called the bridge site on anatase TiO2(001) - 1 X 1 surface. However, for 0.25 monolayer coverage, Au atoms energetically prefer to stay at 0.64 angstrom above the midpoint of the two surface oxygens which is significantly closer to the surface layer. When implanted inside the slab for full coverage, Au forms parallel metallic wires inside TiO2 lattice where interlayer distances increase due to local segregation. Au brings half-filled impurity states into the band gap leading to metallization, in addition to other filled surface and impurity bands within the gap. These Au-driven Fermi-level-pinning gap states are close to, or even in some cases inside, the conduction band of the host slab. On the other hand, if Au is substituted for the surface Ti atom, Fermi level falls lower in the gap closer to the valence-band top.

Subject Keywords

Electronic, Optical and Magnetic Materials, Condensed Matter Physics

URI

https://hdl.handle.net/11511/51614

Journal

PHYSICAL REVIEW B

DOI

https://doi.org/10.1103/physrevb.80.035422

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

Variational formulation of irreversible thermodynamics of surfaces and interfaces with grain-boundary triple-junction singularities under the capillary and electromigration forces in anisotropic two-dimensional space Ogurtani, TO (American Physical Society (APS), 2006-06-01) A variational irreversible thermodynamic method for curved surfaces and interfaces in a two-dimensional (2D) continuum, having anisotropic specific surface Gibbs free energy, is developed by utilizing the more realistic monolayer model of Verschaffelt and Guggenheim for the description of interfaces and surfaces in connection with the global entropy production hypothesis. This approach considers not only the asymmetric disposition of the grain-boundary triple junction, but also its dynamical effects on the ...
Theoretical investigation of intersubband nonlinear optical rectification in AlxlGa1-xlAs/GaAs/AlxrGa1-xrAs asymmetric rectangular quantum wells Karabulut, Ibrahim; Atav, Uelfet; Safak, Haluk; Tomak, Mehmet (Wiley, 2007-09-01) In this study, a theoretical investigation of intersubband nonlinear optical rectification in Alx1Ga1-x1As/ GaAs/AlxrGa1-xrAs asymmetric rectangular quantum wells is presented. The electronic states in the asymmetric rectangular quantum well are described within the framework of the envelope function approach including the effects of band nonparabolicity and the effective mass mismatch. The nonlinear optical rectification is calculated using the density matrix formalism. It is found that the nonlinear optic...
Effects of Si nanowire on the device properties of n-ZnSe/p-Si heterostructure COŞKUN, EMRE; Gullu, H. H.; Colakoglu, T.; Emir, C.; Bozdogan, E.; Parlak, Mehmet (Springer Science and Business Media LLC, 2019-03-01) The semiconductor nanowire (NW) technology has raised attention owing to its one-dimensional geometry as a solution for lattice mismatch in the fabricated heterostructures. Although, SiNWs have been investigated for various device technologies, there is no published work on the p-n junction formed by deposition of ZnSe thin film on these NW structures, in which this film layer has significant optical and electrical properties in optoelectronics applications. The aim of this study is determining the device p...
Electronic structure of a many-electron spherical quantum dot with an impurity Sahin, M; Tomak, Mehmet (American Physical Society (APS), 2005-09-01) We investigate the electronic structure of a many-electron spherical quantum dot with and without hydrogenic impurity. The number of electrons is taken as N=18. The density functional theory is used within local density approximation. Total energy, chemical potential, addition energy spectra, and the shell structure are determined and the results obtained are compared for cases with and without impurity. It is observed that the capacitive energy with the impurity increases in the 1s shell with respect to th...
Heating of magnetic fluid systems driven by circularly polarized magnetic field Ahsen, Osman O.; Yilmaz, Ugur; Aksoy, M. Deniz; Ertaş, Gülay; Atalar, Ergin (Elsevier BV, 2010-10-01) A theory is presented to calculate the heat dissipation of a magnetic suspension, a ferrofluid, driven by7 circularly polarized magnetic field. Theory is tested by in vitro experiments and it is shown that, regardless of the character of the relaxation process, linearly and circularly polarized magnetic field excitations, having the same root-mean-square magnitude, are equivalent in terms of heating efficiency.

Citation Formats

E. METE, O. GÜLSEREN, and S. Ş. Ellialtıoğlu, “Modification of TiO2(001) surface electronic structure by Au impurity investigated with density functional theory,” PHYSICAL REVIEW B, pp. 0–0, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51614.