MIT Successfully Freezes Water at Normal Boiling Point
A team of researchers from Massachusetts Institute of Technology has discovered a way to freeze water solid even at high temperature that would normally set it boil.
Their findings, described in a paper published in the journal Nature Nanotechnology, showed that even very familiar materials, like water, could drastically change their behavior when confined in structures measured in nanometers, or billionth of a meter.
"If you confine a fluid to a nanocavity, you can actually distort its phase behavior," explained Michael Strano, the Carbon P. Dubbs Professor in Chemical Engineering at MIT and lead author of the study, in a press release. "The effect is much greater than anyone had anticipated."
It has been widely accepted that water, at sea level, will start to boil at 212 degrees Fahrenheit, or 100 degrees Celsius. Additionally, scientists have previously observed that the boiling point and freezing point of the water can be influenced by the size of its container, dropping by around 10 C or so in confined spaces.
For the study, the researchers used carbon nanotubes to trap the water. These nanotubes have inner dimensions that are not much bigger than a few water molecules. It serves as a really small pipe that were left open at both ends, with reservoir of water at each opening. Using vibrational spectroscopy, the researchers were able to track the movement of water inside the nanotubes.
The researchers discovered that a tiny difference in the diameter of the nanotubes could yield different boiling and freezing point for water. They noted the water that was confined in a really tight carbon nanotube has solidified. Due to the absence of crystalline structure in the frozen water in nanotubes, the researchers refused to call it ice.
The result of their study could open up the path for ice-filled wires, which could take advantage of the unique electrical and thermal properties of water while remaining stable at room temperatures.