TROY, N.Y., Feb. 14 (UPI) -- U.S. scientists say they have discovered how carbon nanotube membranes can be used to control the flow of water with an unprecedented level of precision.
By fusing wet and dry nanotechnologies, researchers at the Rensselaer Polytechnic Institute say the have moved closer to the ability to transform salt water into pure drinking water.
Nanotube membranes can combine high flow rates and high selectivity in filtering very small impurities and other organic materials, such as DNA and proteins, from materials with high water content, the scientists said. The problem is that nanotube arrays are hydrophobic -- they strongly repelling water.
"We have, at a very fundamental level, discovered there is a new mechanism to control water transport," said Nikhil Koratkar, associate professor of mechanical engineering at Rensselaer and lead author of the study. "This is the first time that electrochemical means can be used to control the way that the water interacts with the surface of the nanotube."
The research is to be described in the March 14 issue of the journal Nano Letters.