Stability and formation of hydroxylated α-Al_{2}O_{3}(0001) surfaces at high temperatures

Autor: Jiachen Chen, Dmitry Sharapa, Philipp N. Plessow
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Physical Review Research, Vol 4, Iss 1, p 013232 (2022)
Druh dokumentu: article
ISSN: 2643-1564
DOI: 10.1103/PhysRevResearch.4.013232
Popis: We report a type of termination of the α-Al_{2}O_{3}(0001) surface with low concentration of hydroxyl groups. Using density functional theory calculations, we show that this termination is more stable than previously reported structures for low chemical potentials of water. This means that hydroxyl groups remain thermodynamically stable up to much higher temperatures than predicted previously, for example, up to around 1000 K at 1 mbar partial pressure of water. We also study the formation of these hydroxylated surfaces from adsorbed water and show that the initial steps for surface reconstruction are favorable thermodynamically and also proceed with accessible barriers.
Databáze: Directory of Open Access Journals