Scientists have proven that the freezing temperature of water can be lower than we thought.
A team of engineers at the University of Houston have taken tiny droplets of water up to 150 nanometers in size and accurately measured the critical temperature threshold.
This achievement can help us understand how water freezes, which has implications for a range of scientific fields.
The freezing temperature of small water droplets has been an unresolved challenge.
Through newly developed metrologies, we have been able to probe the freezing of water droplets.
Most of us don't think about water very much because it's so essential to our existence. H2O is not like any other liquid in that it does not behave like one.
Water's behavior has been studied. It tends to form ice crystals at a variety of temperatures, sometimes resisting the process as far as -38 degrees Celsius. The most stubborn water molecule will stick together as ice.
The temperature was pushed down by placing water on a soft surface. They probed the droplets with electrical resistance metrology and the temperature was taken as they froze.
The soft interface between the surface and the tiny droplet seemed to play a role in the suppression of ice nucleation.
As ambient pressure increases, the freezing temperature of water drops. The most pronounced effect was seen in a small droplets of water.
If a water droplet is in contact with a soft interface, the freezing temperature could be lower than on hard surfaces.
A few-nanometer water droplets can avoid freezing if they are in contact with a soft interface.
The freezing of tiny droplets within cells can cause them to die, so it's important that the way water droplets freeze. Learning how to slow or halt that process could help scientists find ways to mitigate that effect.
It could help us understand how nucleation happens in the atmosphere. It could help us to better design technology that suffers from ice exposure, such as aircraft and wind turbine.
The findings are in agreement with classical nucleation theory. They write in their paper that this understanding contributes to a greater knowledge of natural phenomena and rational design of anti-icing systems for aviation, wind energy, and infrastructures.
The findings give an understanding of natural phenomena and provide a route for the design of superior anti-icing biomimetics.
The research has been published.
