Title :

Diffusion in CaCO3 Calcite Investigated by Atomic-Scale Simulations

Author(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]

Journal title :

The Journal of Physical Chemistry C

Abbreviated title :

J. Phys. Chem. C

Volume number :

123

Pages :

21825-21837

Publisher :

American Chemical Society (ACS)

Publication date :

2019-08-14

English keyword(s) :

atomic-scale
calcite
atomic diffusion
carbonation

HAL domain(s) :

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

English abstract : [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 ...
Show more >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.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
CNRS
INRA
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Métallurgie Physique et Génie des Matériaux

Submission date :

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