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Title: Diffusion and selectivity of water confined within metal–organic nanotubes.
Behavior of nanoconfined water in porous materials has important implications for the development of advanced water purification and storage. In the current study, the kinetics of water sorption from the vapor phase into a metal organic nanotube ((C 4 N 2 H 6 )[(UO 2 )(C 4 O 4 NH 5 )(C 4 O 4 NH 6 )]·2H 2 O (UMON)) are investigated with varying relative humidity. The UMON compound contains nanoconfined water molecules arranged in an ice-like array along the length of its one-dimensional pore and exhibits complete specificity to liquid water. Total hydration of the material is observed upon exposure to relative humidity of 60% or higher. Water uptake curves are modeled as diffusion and irreversible condensation in the pore, which leads to a modeled diffusion coefficient of (1.2 ± 0.6) × 10 −12 cm 2 s −1 for water in UMON nanochannels. This value is much lower than observed for other porous material and is most similar to water diffusivity in low-density amorphous ice. In addition, on exposure to various solvent vapors, the UMON material maintained specificity for water in the gas phase.  more » « less
Award ID(s):
1309366
PAR ID:
10079460
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
6
Issue:
4
ISSN:
2050-7488
Page Range / eLocation ID:
1531 to 1539
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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