Role of confinement and surface affinity on filling mechanisms and sorption hysteresis of water in nanopores

The liquid-vapor transition in cylindrical pores is studied as a function of pore size and hydrophilicity through molecular dynamics simulations with the mW coarse-grained model of water. We identify two distinct filling mechanisms, depending on whether the water-pore interaction is smaller or large...

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Detalles Bibliográficos
Autores: de la Llave, Ezequiel Pablo, Molinero, Valeria, Scherlis Perel, Damian Ariel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/70647
Acceso en línea:http://hdl.handle.net/11336/70647
Access Level:acceso abierto
Palabra clave:NANOPORE
CAPILLARY CONDENSATION
SORPTION ISOTHERM
SORPTION HYSTERESIS
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:The liquid-vapor transition in cylindrical pores is studied as a function of pore size and hydrophilicity through molecular dynamics simulations with the mW coarse-grained model of water. We identify two distinct filling mechanisms, depending on whether the water-pore interaction is smaller or larger than the water-water interaction. In the former case (that we term hydrophobic pore), the formation of the condensed phase proceeds gradually with filling, through the nucleation of a water cluster which grows toward the center of the cavity. In hydrophilic pores, instead, the condensed phase develops in conditions of supersaturation, which in principle become more extreme with increasing pore radius and surface affinity. For highly hydrophilic interfaces (those with adsorption energy for water above 10 kcal/mol), the equilibrium and dynamical properties of water in confinement turn out to be practically independent of water affinity.