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Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
Published on: August 27, 2013
Nanoscale hydrodynamics: enhanced flow in carbon nanotubes
Mainak Majumder1, Nitin Chopra, Rodney Andrews
1Chemical and Materials Engineering Department, University of Kentucky, Lexington, Kentucky 40506, USA.
Nature
|November 4, 2005
Summary
Researchers created nanoscale structures using aligned carbon nanotubes that mimic biological channels. Liquid flow through these carbon nanotube membranes is exceptionally fast due to a nearly frictionless interface.
Area of Science:
- Materials Science
- Nanotechnology
- Fluid Dynamics
Background:
- Biological cellular channels exhibit highly selective transport and rapid flow.
- Mimicking these properties in artificial nanoscale structures is a significant scientific challenge with broad application potential.
Purpose of the Study:
- To investigate liquid flow through membranes composed of aligned carbon nanotubes.
- To determine if these structures can achieve flow rates comparable to biological systems.
Main Methods:
- Fabrication of a membrane consisting of an array of aligned carbon nanotubes.
- Experimental measurement of liquid flow rates through the carbon nanotube membrane.
Main Results:
- Observed liquid flow rates were four to five orders of magnitude faster than predicted by conventional fluid-flow theories.
- The enhanced flow is attributed to an almost frictionless interface between the liquid and the carbon nanotube walls.
Conclusions:
- Aligned carbon nanotube membranes can facilitate extraordinarily fast liquid transport.
- The near-frictionless interface is the key mechanism driving this high-velocity flow.
- These findings open avenues for novel applications in nanoscale fluidics.
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