Related Experiment Video
Updated: Jul 28, 2025

Author Spotlight: Unlocking Plant Transformation by Innovating with Carbon Nanofiber Arrays
Published on: July 21, 2023
Fast Water Transport through Subnanometer Diameter Vertically Aligned Carbon Nanotube Membranes
Da-Chi Yang1, Richard J Castellano2, Ricardo Prada Silvy2
1Mechanical and Aerospace Engineering, Rutgers University, Piscataway, New Jersey 08854, United States.
Abstract:
Small-diameter carbon nanotubes (CNTs) have outstanding mass-transport properties, especially enhanced water flow. Here, we report on water transport through the first macroscopic membranes with vertically oriented, subnanometer (0.8 nm) CNT pores, made by a scalable, solution-based method with electric-field alignment of bulk-grown single-wall CNTs (SWCNTs). After plasma etching to open pores, vertically aligned CNTs served as the primary pathway for liquid-water transport. The CNT membranes showed fast pressure-driven water transport, with up to 105-fold enhancement compared to no-slip Hagen-Poiseuille flow. Comparing 0.8 and 3 nm CNTs, we found that the hydrodynamic slip lengths increased with decreasing nanotube diameter, reaching 8.5 μm for the smaller-diameter CNTs. The results suggest that pressure-driven water transport in small-diameter CNTs is increasingly dominated by entrance resistance, thus becoming independent of nanotube length. Scalably fabricated membranes incorporating vertically aligned subnanometer CNT pores could have applications in water filtration, desalination, and energy harvesting.
Related Concept Videos
Facilitated Transport
Transcellular Transport of Solutes
Short-distance Transport of Resources
Aquaporins
The Significance of Membrane Transport
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
Fluid Movement Between Compartments

