Water friction in nanofluidic channels made from two-dimensional crystals

Ashok Keerthi, Solleti Goutham, Yi You, Pawin Iamprasertkun, Robert A.W. Dryfe, Andre K. Geim, Boya Radha

Research output: Contribution to journalArticlepeer-review


Membrane-based applications such as osmotic power generation, desalination and molecular separation would benefit from decreasing water friction in nanoscale channels. However, mechanisms that allow fast water flows are not fully understood yet. Here we report angstrom-scale capillaries made from atomically flat crystals and study the effect of confining walls’ material on water friction. A massive difference is observed between channels made from isostructural graphite and hexagonal boron nitride, which is attributed to different electrostatic and chemical interactions at the solid-liquid interface. Using precision microgravimetry and ion streaming measurements, we evaluate the slip length, a measure of water friction, and investigate its possible links with electrical conductivity, wettability, surface charge and polarity of the confining walls. We also show that water friction can be controlled using hybrid capillaries with different slip lengths at opposing walls. The reported advances extend nanofluidics’ toolkit for designing smart membranes and mimicking manifold machinery of biological channels.

Original languageEnglish
Article number3092
JournalNature Communications
Issue number1
Early online date25 May 2021
Publication statusPublished - 1 Dec 2021


Dive into the research topics of 'Water friction in nanofluidic channels made from two-dimensional crystals'. Together they form a unique fingerprint.

Cite this