Agoston, Peter
:
Point defect and surface properties of In2O3 and SnO2: A comparative study by first-principles methods.
[Online-Edition: urn:nbn:de:tuda-tuprints-27811]
TU Darmstadt
, Darmstadt
[Dissertation], (2011)
Kurzbeschreibung (Abstract)
The first part of the dissertation deals with the thermodynamic stability of point defects in In2O3 and SnO2. This is done by first surveying possible defect geometries using density functional theory (DFT) total energy calculations in order to identify relevant structures. The formation energies of selected defects are then further refined by estimating their formation entropies as well as by using more sophisticated DFT approximations like hybrid-functionals. The second part deals with the kinetic properties of point defects. The migration barriers of a range of defects is calculated in various charge states in order to estimate the diffusion constants and equilibration temperatures. The third part finally turns to the surface properties of In2O3 and SnO2. First, the controversially discussed thermodynamic ground state properties of SnO2 surfaces are resolved and complemented. Then a detailed survey on the stability and structure of surfaces is conducted for In2O3 surfaces. The influence of water, strain, dopants and band bending are discussed and linked to experimental observations. Finally, the properties of bulk defects and surfaces are compared for the two materials.
| Typ des Eintrags: | Dissertation | ||||
|---|---|---|---|---|---|
| Erschienen: | 2011 | ||||
| Autor(en): | Agoston, Peter | ||||
| Titel: | Point defect and surface properties of In2O3 and SnO2: A comparative study by first-principles methods | ||||
| Sprache: | Englisch | ||||
| Kurzbeschreibung (Abstract): | The first part of the dissertation deals with the thermodynamic stability of point defects in In2O3 and SnO2. This is done by first surveying possible defect geometries using density functional theory (DFT) total energy calculations in order to identify relevant structures. The formation energies of selected defects are then further refined by estimating their formation entropies as well as by using more sophisticated DFT approximations like hybrid-functionals. The second part deals with the kinetic properties of point defects. The migration barriers of a range of defects is calculated in various charge states in order to estimate the diffusion constants and equilibration temperatures. The third part finally turns to the surface properties of In2O3 and SnO2. First, the controversially discussed thermodynamic ground state properties of SnO2 surfaces are resolved and complemented. Then a detailed survey on the stability and structure of surfaces is conducted for In2O3 surfaces. The influence of water, strain, dopants and band bending are discussed and linked to experimental observations. Finally, the properties of bulk defects and surfaces are compared for the two materials. |
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| Ort: | Darmstadt | ||||
| Fachbereich(e)/-gebiet(e): | Fachbereich Material- und Geowissenschaften > Materialwissenschaften > Materialmodellierung Fachbereich Material- und Geowissenschaften > Materialwissenschaften Fachbereich Material- und Geowissenschaften |
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| Hinterlegungsdatum: | 04 Nov 2011 12:23 | ||||
| Offizielle URL: | urn:nbn:de:tuda-tuprints-27811 | ||||
| Gutachter / Prüfer: | Albe, Prof. Karsten ; von Seggern, Prof. Heinz | ||||
| Datum der Begutachtung bzw. der mündlichen Prüfung / Verteidigung / mdl. Prüfung: | 6 Juli 2011 | ||||
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