Stability of Hydroxylated α-Fe 2 O 3 (0001) Surfaces.

Autor: Chen J; Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany., Sharapa DI; Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany., Plessow PN; Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
Jazyk: angličtina
Zdroj: ACS omega [ACS Omega] 2024 Aug 05; Vol. 9 (33), pp. 35449-35457. Date of Electronic Publication: 2024 Aug 05 (Print Publication: 2024).
DOI: 10.1021/acsomega.4c02113
Abstrakt: The stability of hydroxylated terminations of the 0001 surface of α-Fe 2 O 3 (hematite) is investigated computationally using PBE + U calculations with dispersion corrections. Hydroxylated surfaces with low OH concentrations are found to be most stable in a range of the chemical potential of water of -0.95 eV > μ H 2 O > -2.22 eV. These surfaces can be described as isolated Fe(OH) 3 groups adsorbed on the dry hematite surface and are predicted to be the exposed termination of the 0001 surface in a wide range of relevant experimental conditions. Most investigated reduced surfaces, containing Fe in oxidation state +2, are only stable in a range of the chemical potential of oxygen μ O < -2.44 eV, where bulk hematite is less than magnetite. The only reduced surface stable at a higher μ O is derived from the most stable nonreduced hydroxylated surfaces by removing a single OH group per unit cell.
Competing Interests: The authors declare no competing financial interest.
(© 2024 The Authors. Published by American Chemical Society.)
Databáze: MEDLINE
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