Water filling of hydrophilic nanopores

Molecular dynamics simulations of water in cylindrical hydrophilic pores with diameters of 1.5 and 3 nm were performed to explore the phase behavior and the nucleation dynamics of the confined fluid as a function of the percentage of volume filled f. The interactions of water with the pore wall were...

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Autores principales: De La Llave, E., Molinero, V., Scherlis, D.A.
Formato: Artículo publishedVersion
Lenguaje:Inglés
Publicado: 2010
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Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00219606_v133_n3_p_DeLaLlave
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spelling paperaa:paper_00219606_v133_n3_p_DeLaLlave2023-06-12T16:43:22Z Water filling of hydrophilic nanopores J Chem Phys 2010;133(3) De La Llave, E. Molinero, V. Scherlis, D.A. Capillary condensation Confined fluids Hydrophilic pores Liquid Phase Liquid plugs Low water-content Molecular dynamics simulations Nucleation mechanism Percentage of volume Phase co-existence Pore wall Second phase Silica pores Surface hydrophilicity Surface phasis Surface supersaturation Two-phase equilibria Water cluster Water filling Water molecule Water surface Condensation Filling Hydrophilicity Liquids Molecular dynamics Monolayers Nanopores Nucleation Phase equilibria Silica Supersaturation Water content Molecular dynamics simulations of water in cylindrical hydrophilic pores with diameters of 1.5 and 3 nm were performed to explore the phase behavior and the nucleation dynamics of the confined fluid as a function of the percentage of volume filled f. The interactions of water with the pore wall were considered to be identical to the interactions between water molecules. At low water contents, all the water is adsorbed to the surface of the pore. A second phase consisting of a liquid plug appears at the onset filling for capillary condensation, fonset =27% and 34% for the narrow and wide pores, respectively. In agreement with experimental results for silica pores, the liquid phase appears close to the equilibrium filling feq in the 1.5 nm pore and under conditions of strong surface supersaturations for the 3 nm pore. After condensation, two phases, a liquid plug and a surface-adsorbed phase, coexist in equilibrium. Under conditions of phase coexistence, the water surface density Tcoex was found to be independent of the water content and the diameter of the pore. The value of Tcoex found in the simulations (∼3 nm-2) is in good agreement with experimental results for silica pores, suggesting that the interactions of water with silica and with itself are comparable. The surface-adsorbed phase at coexistence is a sparse monolayer with a structure dominated by small water clusters. We characterize the density and structure of the liquid and surface phases, the nucleation mechanism of the water plug, and the effect of surface hydrophilicity on the two-phase equilibrium and hysteresis. The results are discussed in light of experiments and previous simulations. © 2010 American Institute of Physics. Fil:De La Llave, E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Molinero, V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2010 info:eu-repo/semantics/article info:ar-repo/semantics/artículo info:eu-repo/semantics/publishedVersion application/pdf eng info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00219606_v133_n3_p_DeLaLlave
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
language Inglés
orig_language_str_mv eng
topic Capillary condensation
Confined fluids
Hydrophilic pores
Liquid Phase
Liquid plugs
Low water-content
Molecular dynamics simulations
Nucleation mechanism
Percentage of volume
Phase co-existence
Pore wall
Second phase
Silica pores
Surface hydrophilicity
Surface phasis
Surface supersaturation
Two-phase equilibria
Water cluster
Water filling
Water molecule
Water surface
Condensation
Filling
Hydrophilicity
Liquids
Molecular dynamics
Monolayers
Nanopores
Nucleation
Phase equilibria
Silica
Supersaturation
Water content
spellingShingle Capillary condensation
Confined fluids
Hydrophilic pores
Liquid Phase
Liquid plugs
Low water-content
Molecular dynamics simulations
Nucleation mechanism
Percentage of volume
Phase co-existence
Pore wall
Second phase
Silica pores
Surface hydrophilicity
Surface phasis
Surface supersaturation
Two-phase equilibria
Water cluster
Water filling
Water molecule
Water surface
Condensation
Filling
Hydrophilicity
Liquids
Molecular dynamics
Monolayers
Nanopores
Nucleation
Phase equilibria
Silica
Supersaturation
Water content
De La Llave, E.
Molinero, V.
Scherlis, D.A.
Water filling of hydrophilic nanopores
topic_facet Capillary condensation
Confined fluids
Hydrophilic pores
Liquid Phase
Liquid plugs
Low water-content
Molecular dynamics simulations
Nucleation mechanism
Percentage of volume
Phase co-existence
Pore wall
Second phase
Silica pores
Surface hydrophilicity
Surface phasis
Surface supersaturation
Two-phase equilibria
Water cluster
Water filling
Water molecule
Water surface
Condensation
Filling
Hydrophilicity
Liquids
Molecular dynamics
Monolayers
Nanopores
Nucleation
Phase equilibria
Silica
Supersaturation
Water content
description Molecular dynamics simulations of water in cylindrical hydrophilic pores with diameters of 1.5 and 3 nm were performed to explore the phase behavior and the nucleation dynamics of the confined fluid as a function of the percentage of volume filled f. The interactions of water with the pore wall were considered to be identical to the interactions between water molecules. At low water contents, all the water is adsorbed to the surface of the pore. A second phase consisting of a liquid plug appears at the onset filling for capillary condensation, fonset =27% and 34% for the narrow and wide pores, respectively. In agreement with experimental results for silica pores, the liquid phase appears close to the equilibrium filling feq in the 1.5 nm pore and under conditions of strong surface supersaturations for the 3 nm pore. After condensation, two phases, a liquid plug and a surface-adsorbed phase, coexist in equilibrium. Under conditions of phase coexistence, the water surface density Tcoex was found to be independent of the water content and the diameter of the pore. The value of Tcoex found in the simulations (∼3 nm-2) is in good agreement with experimental results for silica pores, suggesting that the interactions of water with silica and with itself are comparable. The surface-adsorbed phase at coexistence is a sparse monolayer with a structure dominated by small water clusters. We characterize the density and structure of the liquid and surface phases, the nucleation mechanism of the water plug, and the effect of surface hydrophilicity on the two-phase equilibrium and hysteresis. The results are discussed in light of experiments and previous simulations. © 2010 American Institute of Physics.
format Artículo
Artículo
publishedVersion
author De La Llave, E.
Molinero, V.
Scherlis, D.A.
author_facet De La Llave, E.
Molinero, V.
Scherlis, D.A.
author_sort De La Llave, E.
title Water filling of hydrophilic nanopores
title_short Water filling of hydrophilic nanopores
title_full Water filling of hydrophilic nanopores
title_fullStr Water filling of hydrophilic nanopores
title_full_unstemmed Water filling of hydrophilic nanopores
title_sort water filling of hydrophilic nanopores
publishDate 2010
url http://hdl.handle.net/20.500.12110/paper_00219606_v133_n3_p_DeLaLlave
work_keys_str_mv AT delallavee waterfillingofhydrophilicnanopores
AT molinerov waterfillingofhydrophilicnanopores
AT scherlisda waterfillingofhydrophilicnanopores
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