One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes

The effect of nanoconfinement on the self-dissociation of water constitutes an open problem whose elucidation poses a serious challenge to experiments and simulations alike. In slit pores of width ?1 nm, recent first-principles calculations have predicted that the dissociation constant of H2O increa...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Sirkin, Y.A.P., Hassanali, A., Scherlis, D.A.
Formato: JOUR
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_19487185_v9_n17_p5029_Sirkin
Aporte de:
id todo:paper_19487185_v9_n17_p5029_Sirkin
record_format dspace
spelling todo:paper_19487185_v9_n17_p5029_Sirkin2023-10-03T16:37:12Z One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes Sirkin, Y.A.P. Hassanali, A. Scherlis, D.A. Calculations Carbon nanotubes Equilibrium constants Free energy Molecular dynamics Pore size Yarn Biased sampling Characteristic length Dissociation constant First-principles calculation Hydronium ions Nanoconfinements Orders of magnitude Water dissociation Dissociation The effect of nanoconfinement on the self-dissociation of water constitutes an open problem whose elucidation poses a serious challenge to experiments and simulations alike. In slit pores of width ?1 nm, recent first-principles calculations have predicted that the dissociation constant of H2O increases by almost 2 orders of magnitude [ Muñoz-Santiburcio and Marx, Phys. Rev. Lett. 2017, 119, 056002 ]. In the present study, quantum mechanics?molecular mechanics simulations are employed to compute the dissociation free-energy profile of water in a (6,6) carbon nanotube. According to our results, the equilibrium constant Kw drops by 3 orders of magnitude with respect to the bulk phase value, at variance with the trend predicted for confinement in two dimensions. The higher barrier to dissociation can be ascribed to the undercoordination of the hydroxide and hydronium ions in the nanotube and underscores that chemical reactivity does not exhibit a monotonic behavior with respect to pore size but may vary substantially with the characteristic length scale and dimensionality of the confining media. © 2018 American Chemical Society. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_19487185_v9_n17_p5029_Sirkin
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Calculations
Carbon nanotubes
Equilibrium constants
Free energy
Molecular dynamics
Pore size
Yarn
Biased sampling
Characteristic length
Dissociation constant
First-principles calculation
Hydronium ions
Nanoconfinements
Orders of magnitude
Water dissociation
Dissociation
spellingShingle Calculations
Carbon nanotubes
Equilibrium constants
Free energy
Molecular dynamics
Pore size
Yarn
Biased sampling
Characteristic length
Dissociation constant
First-principles calculation
Hydronium ions
Nanoconfinements
Orders of magnitude
Water dissociation
Dissociation
Sirkin, Y.A.P.
Hassanali, A.
Scherlis, D.A.
One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes
topic_facet Calculations
Carbon nanotubes
Equilibrium constants
Free energy
Molecular dynamics
Pore size
Yarn
Biased sampling
Characteristic length
Dissociation constant
First-principles calculation
Hydronium ions
Nanoconfinements
Orders of magnitude
Water dissociation
Dissociation
description The effect of nanoconfinement on the self-dissociation of water constitutes an open problem whose elucidation poses a serious challenge to experiments and simulations alike. In slit pores of width ?1 nm, recent first-principles calculations have predicted that the dissociation constant of H2O increases by almost 2 orders of magnitude [ Muñoz-Santiburcio and Marx, Phys. Rev. Lett. 2017, 119, 056002 ]. In the present study, quantum mechanics?molecular mechanics simulations are employed to compute the dissociation free-energy profile of water in a (6,6) carbon nanotube. According to our results, the equilibrium constant Kw drops by 3 orders of magnitude with respect to the bulk phase value, at variance with the trend predicted for confinement in two dimensions. The higher barrier to dissociation can be ascribed to the undercoordination of the hydroxide and hydronium ions in the nanotube and underscores that chemical reactivity does not exhibit a monotonic behavior with respect to pore size but may vary substantially with the characteristic length scale and dimensionality of the confining media. © 2018 American Chemical Society.
format JOUR
author Sirkin, Y.A.P.
Hassanali, A.
Scherlis, D.A.
author_facet Sirkin, Y.A.P.
Hassanali, A.
Scherlis, D.A.
author_sort Sirkin, Y.A.P.
title One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes
title_short One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes
title_full One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes
title_fullStr One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes
title_full_unstemmed One-Dimensional Confinement Inhibits Water Dissociation in Carbon Nanotubes
title_sort one-dimensional confinement inhibits water dissociation in carbon nanotubes
url http://hdl.handle.net/20.500.12110/paper_19487185_v9_n17_p5029_Sirkin
work_keys_str_mv AT sirkinyap onedimensionalconfinementinhibitswaterdissociationincarbonnanotubes
AT hassanalia onedimensionalconfinementinhibitswaterdissociationincarbonnanotubes
AT scherlisda onedimensionalconfinementinhibitswaterdissociationincarbonnanotubes
_version_ 1782027055293005824