Capillary Rise of Liquids in Nanopores

TL;DR

This study investigates the capillary rise of various liquids in nanoporous Vycor glass, confirming that imbibition follows the Lucas-Washburn law and scales with bulk fluid properties.

Contribution

It provides experimental validation of the Lucas-Washburn law at the nanoscale for different liquids in nanopores.

Findings

Imbibition follows the Lucas-Washburn square root of time law.

Capillary rise velocities scale with bulk fluid parameters.

Results confirm the applicability of classical models at the nanoscale.

Abstract

We present measurements on the spontaneous imbibition (capillary rise) of water, a linear hydrocarbon (n-C16H34) and a liquid crystal (8OCB) into the pore space of monolithic, nanoporous Vycor glass (mean pore radius 5 nm). Measurements on the mass uptake of the porous hosts as a function of time, m(t), are in good agreement with the Lucas-Washburn square root of time prediction, typical of imbibition of liquids into porous hosts. The relative capillary rise velocities scale as expected from the bulk fluid parameters.