MIT researchers discover amazing new property of water that could lead to ice filled wires

**MIT** researchers have learnt something unexpected about water. Inside really confined spaces, such as carbon nanotubes, water freezes at temperatures where it would normally boil. The inner dimensions of these carbon nanotubes are not more than a few water molecules in diameter. Ice has unique electrical and thermal properties that can potentially lead to ice filled wires. The discovery shows how even commonplace materials can behave unexpectedly in extremely confined spaces. The diameter of the nano tubes are critical for the unique properties of water to be seen. A difference of 10 degrees was observed in the freezing points of water in tubes that were 1.05 nanometers across compared to tubes that were 1.06 nanometers across.  The tubes were tested with water reservoirs on either end. In previous such efforts to understand the behavior of liquids in confined places, the results were unpredictable because of the inability of researchers to measure the inner diameters of nanotubes with precision. Carbon nanotubes are believed to be hydrophobic, where the surfaces naturally repel water. It is a mystery how water even gets into such small nanotubes. The researchers are using highly sensitive imaging technology called vibrational spectroscopy to study the movement of the water within the tube, the first time such a detailed measurement has been undertaken. While the team has observed a solid ice like stage within the nanotubes, the researchers are hesitant to call it ice because they have not yet conclusively proved that the solid material has crystalline structures seen in ice. The “ice wires” have a potential to be the best conductive material for protons, because water conducts protons ten times more readily than conventional conductive materials. The research is being reported in the journal called Nature Nanotechnology.