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Title: Surface hydration drives rapid water imbibition into strongly hydrophilic nanopores
The imbibition of liquids into nanopores plays a critical role in numerous applications, and most prior studies focused on imbibition due to capillary flows. Here we report molecular simulations of the imbibition of water into single mica nanopores filled with pressurized gas. We show that, while capillary flow is suppressed by the high gas pressure, water is imbibed into the nanopore through surface hydration in the form of monolayer liquid films. As the imbibition front moves, the water film behind it gradually densifies. Interestingly, the propagation of the imbibition front follows a simple diffusive scaling law. The effective diffusion coefficient of the imbibition front, however, is more than ten times larger than the diffusion coefficient of the water molecules in the water film adsorbed on the pore walls. We clarify the mechanism for the rapid water imbibition observed here.  more » « less
Award ID(s):
1705287
PAR ID:
10062498
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
19
Issue:
31
ISSN:
1463-9076
Page Range / eLocation ID:
20506 to 20512
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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