Molecular streaming and its voltage control in ångström-scale channels

T. Mouterde, A. Keerthi, A. R. Poggioli, S. A. Dar, A. Siria, A. K. Geim (), L. Bocquet () and B. Radha ()
Additional contact information
T. Mouterde: Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité
A. Keerthi: University of Manchester
A. R. Poggioli: Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité
S. A. Dar: University of Manchester
A. Siria: Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité
A. K. Geim: University of Manchester
L. Bocquet: Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité
B. Radha: University of Manchester

Nature, 2019, vol. 567, issue 7746, 87-90

Abstract: Abstract Over the past decade, the ability to reduce the dimensions of fluidic devices to the nanometre scale (by using nanotubes1–5 or nanopores6–11, for example) has led to the discovery of unexpected water- and ion-transport phenomena12–14. More recently, van der Waals assembly of two-dimensional materials15 has allowed the creation of artificial channels with ångström-scale precision16. Such channels push fluid confinement to the molecular scale, wherein the limits of continuum transport equations17 are challenged. Water films on this scale can rearrange into one or two layers with strongly suppressed dielectric permittivity18,19 or form a room-temperature ice phase20. Ionic motion in such confined channels21 is affected by direct interactions between the channel walls and the hydration shells of the ions, and water transport becomes strongly dependent on the channel wall material22. We explore how water and ionic transport are coupled in such confinement. Here we report measurements of ionic fluid transport through molecular-sized slit-like channels. The transport, driven by pressure and by an applied electric field, reveals a transistor-like electrohydrodynamic effect. An applied bias of a fraction of a volt increases the measured pressure-driven ionic transport (characterized by streaming mobilities) by up to 20 times. This gating effect is observed in both graphite and hexagonal boron nitride channels but exhibits marked material-dependent differences. We use a modified continuum framework accounting for the material-dependent frictional interaction of water molecules, ions and the confining surfaces to explain the differences observed between channels made of graphene and hexagonal boron nitride. This highly nonlinear gating of fluid transport under molecular-scale confinement may offer new routes to control molecular and ion transport, and to explore electromechanical couplings that may have a role in recently discovered mechanosensitive ionic channels23.

Date: 2019
References: Add references at CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
https://www.nature.com/articles/s41586-019-0961-5 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:567:y:2019:i:7746:d:10.1038_s41586-019-0961-5

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-019-0961-5

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().