Oxygen vacancy diffusion in alumina: New atomistic simulation methods applied to an old problem

Bowen, Paul; Parker, Stephen C.

doi:10.1016/j.actamat.2009.06.061

Cited by 38 publications

(43 citation statements)

References 37 publications

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“…It is an adaption of an earlier force field [7,15,16]. The earlier force field [7,15,16] has been shown repeatedly to give good results for the description of inorganic oxide crystals [7,[17][18][19]. Freeman et al have shown that with a slight adaption the force field can be used in connection with rigid molecule water force fields.…”

Section: Potentialmentioning

confidence: 99%

Changes in portlandite morphology with solvent composition: Atomistic simulations and experiment

Galmarini

Aimable

Ruffray

et al. 2011

Cement and Concrete Research

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Experimental work has been done to determine changes in the particle shape of portlandite grown in the presence of different ions. To quantify the experimentally observed changes in morphology a new analysis tool was developed, allowing the calculation of the relative surface energies of the crystal facets. The observed morphology in the presence of chlorides and nitrates was facetted particles of a similar shape, the addition of sulfates leads to hexagonal platelet morphology and the addition of silicates leads to the formation of large irregular aggregates. In addition to the experimental work, the surfaces of portlandite were studied with atomistic simulation techniques. The empirical force field used has first been validated. The equilibrium morphology of portlandite in vacuum and in water was then calculated. The results indicate that the presence of water stabilizes the [20.3] surface and changes the morphology. This is consistent with the experimental observation of [20.3] surfaces.

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Section: Potentialmentioning

confidence: 99%

Changes in portlandite morphology with solvent composition: Atomistic simulations and experiment

Galmarini

Aimable

Ruffray

et al. 2011

Cement and Concrete Research

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“…Furthermore, many theoretical studies of defects in Al 2 O 3 have been reported based on classical interatomic potential [6][7][8][9][10], semi-empirical [11][12][13], Hartree-Fock [14], density functional [15,16], and most recently hybrid density functional methods [17,18]. Many of these studies have focused on the F-centre associated with oxygen vacancy formation, while the nature of oxygen interstitial structure and spin configuration has received much less attention.…”

Section: Introductionmentioning

confidence: 98%

Oxygen interstitial structures in close-packed metal oxides

Sokol

Walsh

Catlow

2010

Chemical Physics Letters

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“…19 Both studies (Refs. 16 and 19) pointed out that there were multiple elementary routes contributing to the overall O diffusion processes in alumina.…”

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confidence: 99%

“…In particular, we modeled the O and Al grain-boundary diffusion processes in alumina along both low-energy and high-energy representative GBs. In most of previous atomistic simulations, 16,17,19 some kinds of empirical potentials were used when modeling the diffusion processes in alumina. The reliability and accuracy of the predictions from these atomistic simulations strongly depended on the quality of the employed empirical potentials.…”

mentioning

confidence: 99%

Density functional calculation of activation energies for lattice and grain boundary diffusion in alumina

et al. 2013

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To acquire knowledge on the lattice and grain-boundary diffusion processes in alumina, we have determined the activation energies of elementary O and Al diffusive jumps in the bulk crystal, Σ3(0001) grain boundaries, and Σ3(101 0) grain boundaries of α-Al 2 O 3 using the first-principles density functional theory method. Specifically, we calculated the activation energies for four elementary jumps of both O and Al lattice diffusion in alumina. It was predicted that the activation energy of O lattice diffusion varied from 3.58 eV to 5.03 eV while the activation energy of Al lattice diffusion ranged from 1.80 eV to 3.17 eV. As compared with experimental measurements, the theoretical predictions of the activation energy for lattice diffusion were lower and thus implied that there might be other high-energy diffusive jumps in the experimental alumina samples. Moreover, our results suggested that the Al lattice diffusion was faster than the O lattice diffusion in alumina, in agreement with experiment observations. Furthermore, it was found from our calculations for α-Al 2 O 3 that the activation energies of O and Al grain-boundary diffusion in the high-energy Σ3(0001) grain boundaries were significantly lower than those of the lattice diffusion. In contrast, the activation energies of O and Al grain-boundary diffusion in the low-energy Σ3(101 0) grain boundaries could be even higher than those of the lattice diffusion.--

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Oxygen vacancy diffusion in alumina: New atomistic simulation methods applied to an old problem

Cited by 38 publications

References 37 publications

Changes in portlandite morphology with solvent composition: Atomistic simulations and experiment

Changes in portlandite morphology with solvent composition: Atomistic simulations and experiment

Oxygen interstitial structures in close-packed metal oxides

Density functional calculation of activation energies for lattice and grain boundary diffusion in alumina

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