The effect of stoichiometry on the stability of steps on TiO2(1 1 0)
| Autor: | J. Verhoeven, M.J.J. Jak, Joost W. M. Frenken, A. van Kreuningen |
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| Rok vydání: | 2002 |
| Předmět: |
Chemistry
Hexagonal crystal system Annealing (metallurgy) Atomic force microscopy General Physics and Astronomy Surfaces and Interfaces General Chemistry Crystal structure Condensed Matter Physics Surfaces Coatings and Films Partial oxygen Titanium oxide Crystallography Electrical resistivity and conductivity Chemical physics Stoichiometry |
| Zdroj: | Applied Surface Science. 201:161-170 |
| ISSN: | 0169-4332 |
| DOI: | 10.1016/s0169-4332(02)00844-9 |
| Popis: | The equilibrium composition of titanium oxide depends on temperature and partial oxygen pressure. Deviations from the TiO 2 stoichiometry cause changes in colour and an increase in electrical conductivity. In this study we use ex situ atomic force microscopy observations to show that changes in stoichiometry also affect the morphology of steps on the TiO 2 (1 1 0) surface. Upon annealing of a sputtered stoichiometric surface at 1135 K, first hexagonal islands are formed. During further annealing these hexagonal shapes do not simply grow in size. Instead elongated structures form along the [0 0 1] direction, and the surface tends to maximize the length of the [0 0 1] steps. We propose that the formation of a [0 0 1] step allows the surface to make a non-stoichiometric structure without destroying the crystal structure. |
| Databáze: | OpenAIRE |
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