Titre :

Diffusion in CaCO3 Calcite Investigated by Atomic-Scale Simulations

Auteur(s) :

Besson, Rémy [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Tingaud, David [Auteur]
Laboratoire des Sciences des Procédés et des Matériaux [LSPM]
Favergeon, Loïc [Auteur]
Laboratoire Georges Friedel [LGF-ENSMSE]

Titre de la revue :

The Journal of Physical Chemistry C

Nom court de la revue :

J. Phys. Chem. C

Numéro :

123

Pagination :

21825-21837

Éditeur :

American Chemical Society (ACS)

Date de publication :

2019-08-14

Mot(s)-clé(s) en anglais :

atomic-scale
calcite
atomic diffusion
carbonation

Discipline(s) HAL :

Chimie/Matériaux
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]

Résumé en anglais : [en]

In the context of CO2 storage, we used ab initio-based atomic-scale modelings and simulations to study oxygen and carbon diffusion in CaCO3 calcite. In overall agreement with earlier experimental findings, oxygen diffusion ...
Lire la suite >In the context of CO2 storage, we used ab initio-based atomic-scale modelings and simulations to study oxygen and carbon diffusion in CaCO3 calcite. In overall agreement with earlier experimental findings, oxygen diffusion is found to take place possibly by either interstitial or vacancy mechanisms depending on the thermodynamic conditions. Contrary to almost isotropic interstitial diffusion, the vacancy mechanism strongly favors oxygen jumps within (111) planes characteristic of the CaCO3 layered structure, with significant less-than-unity correlation factors. Our simulations show that such mechanisms cannot be applied to carbon, and complex point defects may be required to explain the diffusion of this element. While stability arguments indicate that vacancy complexes formed with CO or CO3 missing groups may be efficient candidates to convey C diffusion, no low-energy migration path could be identified for these complexes. Focusing on the mostly stable CO vacancy complex and using generic values for unknown migration energies, kinetic Monte Carlo simulations show that this complex mechanism may be responsible for C diffusion roughly 2 orders of magnitude above its oxygen counterpart.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Établissement(s) :

Université de Lille
CNRS
INRA
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Équipe(s) de recherche :

Métallurgie Physique et Génie des Matériaux

Date de dépôt :

2020-12-03T09:01:49Z
2020-12-07T10:59:42Z
2021-02-09T08:44:00Z