- Tytuł:
- Effect of Annealed (0001) α-$Al_2O_3$ Surfaces on Heteroepitaxial Growth of Silver Nanoparticles
- Autorzy:
- Al-Mohammad, A.
- Powiązania:
- https://bibliotekanauki.pl/articles/1808108.pdf
- Data publikacji:
- 2009-03
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
68.55.-a
81.15.Aa
61.05.jh
61.46.Df - Opis:
- The effect of annealed (0001) α -$Al_2O_3$ surfaces on heteroepitaxial growth of silver nanoparticles were analysed by reflection high-energy electron diffraction, transmission electron microscope and selected area electron diffraction. Ag nanoparticles were deposited on 1× 1 stoichiometric and reconstructed (111)Al//(0001) α -$Al_2O_3$ with the Knudsen cell. The maximum cluster density method and the Lifethenz theory of Van der Waals energy were used to investigate the Ag//(0001)α -$Al_2O_3$ interface parameters. The growth modes, lattice parameters, nanoparticle forms and sizes are strongly dependent on the substrate surface structures. Initially, three-dimensional islands of Ag nanoparticles grow on both kinds of surfaces with partial hexagonal shapes. Ag nanoparticles on stoichiometric surface create the (111)Ag//(0001)α -$Al_2O_3$ interface without any preferred epitaxial direction. On this surface, Gaussian distribution is characteristic of an atom-by-atom growth mode with density of Ag nanoparticles lower than saturation density while a coalescence growth mode appears due to binary collisions between Ag nanoparticles accompanied by a liquid-like behaviour after saturation density. In case of reconstruction substrates, the epitaxial relationships between Ag nanoparticles and the surface are formed (111)Ag//(0001)α -$Al_2O_3$, 〈01\bar(1)〉Ag//[12\bar(3)0]α -$Al_2O_3$ or 〈01\bar(1)〉Ag//[1\bar(1)00]α-$Al_2O_3$. The Ag nanoparticles make rotation with angles between ± 6° around the epitaxial orientations 〈1\bar(1)00〉 or 〈12\bar(3)0〉. Only the atom-by-atom growth mode were found at all Ag nanoparticles growth processes.
- Źródło:
-
Acta Physica Polonica A; 2009, 115, 3; 679-684
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł