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Stability of Hydroxylated α-Fe₂O₃(0001) Surfaces.

ABSTRACT: The stability of hydroxylated terminations of the 0001 surface of α-Fe₂O₃ (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_H₂O > -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.

SUBMITTER: Chen J

PROVIDER: S-EPMC11339807 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Stability of Hydroxylated α-Fe2O3(0001) Surfaces.

Chen Jiachen J Sharapa Dmitry I DI Plessow Philipp N PN

ACS omega 20240805 33

The stability of hydroxylated terminations of the 0001 surface of α-Fe2O3 (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 > μH2O > -2.22 eV. These surfaces can be described as isolated Fe(OH)3 groups adsorbed on the dry hematite surface and are predict ...[more]

PMID: 39184516

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