Interaction of Nitrite Ions with Hydrated Portlandite Surfaces: Atomistic Computer Simulation Study - Archive ouverte HAL
Article Dans Une Revue MATERIALS Année : 2023

Interaction of Nitrite Ions with Hydrated Portlandite Surfaces: Atomistic Computer Simulation Study

Evgeny V Tararushkin
  • Fonction : Auteur
Vasily V Pisarev
  • Fonction : Auteur
Andrey G. Kalinichev
Laboratoire de physique subatomique et des technologies associées
CV

Résumé

The nitrite admixtures in cement and concrete are used as corrosion inhibitors for steel reinforcement and also as anti-freezing agents. The characterization of the protective properties should account for the decrease in the concentration of free NO2− ions in the pores of cement concretes due to their adsorption. Here we applied the classical molecular dynamics computer simulation approach to quantitatively study the molecular scale mechanisms of nitrite adsorption from NaNO2 aqueous solution on a portlandite surface. We used a new parameterization to model the hydrated NO2− ions in combination with the recently upgraded ClayFF force field (ClayFF-MOH) for the structure of portlandite. The new NO2− parameterization makes it possible to reproduce the properties of hydrated NO2− ions in good agreement with experimental data. In addition, the ClayFF-MOH model improves the description of the portlandite structure by explicitly taking into account the bending of Ca-O-H angles in the crystal and on its surface. The simulations showed that despite the formation of a well-structured water layer on the portlandite (001) crystal surface, NO2− ions can be strongly adsorbed. The nitrite adsorption is primarily due to the formation of hydrogen bonds between the structural hydroxyls on the portlandite surface and both the nitrogen and oxygen atoms of the NO2− ions. Due to that, the ions do not form surface adsorption complexes with a single well-defined structure but can assume various local coordinations. However, in all cases, the adsorbed ions did not show significant surface diffusional mobility. Moreover, we demonstrated that the nitrite ions can be adsorbed both near the previously-adsorbed hydrated Na+ ions as surface ion pairs, but also separately from the cations.

Domaines

Physique [physics]

INSPIRE HEP  : Connectez-vous pour contacter le contributeur

https://hal.science/hal-04178843

Soumis le : mardi 8 août 2023-15:36:42

Dernière modification le : mercredi 11 décembre 2024-16:17:48

Consulter le texte intégral

Dates et versions

hal-04178843 , version 1 (08-08-2023)

Identifiants

Citer

Evgeny V Tararushkin, Vasily V Pisarev, Andrey G. Kalinichev. Interaction of Nitrite Ions with Hydrated Portlandite Surfaces: Atomistic Computer Simulation Study. MATERIALS, 2023, 16 (14), pp.5026. ⟨10.3390/ma16145026⟩. ⟨hal-04178843⟩

Exporter

BibTeX XML-TEI Dublin Core DC Terms EndNote DataCite

Collections

IN2P3 SUBATECH CNRS IMT-ATLANTIQUE SUBATECH-RADIOCHIMIE NANTES-UNIVERSITE INSTITUT-MINES-TELECOM
18 Consultations
0 Téléchargements

Altmetric

Partager

More