Featured Research

from universities, journals, and other organizations

Better understanding of water's freezing behavior at nanoscale

Date:
May 21, 2013
Source:
George Washington University
Summary:
The results of a new study provide direct computational evidence that nucleation of ice in small droplets is strongly size-dependent, an important conclusion in understanding water's behavior at the nanoscale.

Ice cube (stock image). According to a new study, nucleation of ice in small droplets is strongly size-dependent, an important conclusion in understanding water's behavior at the nanoscale.
Credit: Natika / Fotolia

The results of a new study led by George Washington University Professor Tianshu Li provide direct computational evidence that nucleation of ice in small droplets is strongly size-dependent, an important conclusion in understanding water's behavior at the nanoscale. The formation of ice at the nanoscale is a challenging, basic scientific research question whose answer also has important implications for climate research and other fields.

The crystallization of ice from supercooled water is generally initiated by a process called nucleation. Because of the speed and size of nucleation -- it occurs within nanoseconds and nanometers -- probing it by experiment or simulation is a major challenge.

By using an advanced simulation method, Dr. Li and his collaborators, Davide Donadio of Germany's Max Planck Institute for Polymer Research, and Giulia Galli, a professor of chemistry and physics at the University of California, Davis, were able to demonstrate that nucleation of ice is substantially suppressed in nano-sized water droplets. Their paper, "Ice nucleation at the nanoscale probes no man's land of water," was published today in the journal Nature Communications.

"A current challenge for scientists is to unveil water's behaviors below -35 degrees Celsius and above -123 degrees Celsius, a temperature range that chemists call 'no man's land,' " said Dr. Li, a professor of civil and environmental engineering at the George Washington University School of Engineering and Applied Science. "Fast ice crystallization can hardly be avoided at such low temperatures, so maintaining water in a liquid state is a major experimental challenge."

Since the frequency of ice nucleation scales with the volume of water, one of the strategies for overcoming this kinetic barrier is to reduce the volume of water. However, this raises the question of whether water at the nanoscale can still be regarded as equivalent to bulk water, and if not, where that boundary would be.

The team's results answer this question. By showing that the ice nucleation rate at the nanoscale can be several orders of magnitude smaller than that of bulk water, they demonstrate that water at such a small scale can no longer be considered bulk water.

"We also predict where this boundary would reside at various temperatures," Dr. Li said. The boundary refers to the size of the droplet where the difference vanishes. The team's findings will help with the interpretation of molecular beam experiments and set the guidelines for experiments that probe the 'no man's land' of water.

The results are also of importance in atmospheric science, as they may improve the climate model of the formation of ice clouds in upper troposphere, which effectively scatter incoming solar radiation and prevent earth from becoming overheated by the sun. The results have important implications in climate control research, too. One of the current debates is whether the formation of ice occurs near the surface or within the micrometer-sized droplets suspended in clouds. If it is the former, effective engineering approaches may be able to be taken to tune the surface tension of water so that the ice crystallization rate can be controlled.

"Our results, indeed, support the hypothesis of surface crystallization of ice in microscopic water droplets," Dr. Li said. "Obtaining the direct evidence is our next step."


Story Source:

The above story is based on materials provided by George Washington University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Tianshu Li, Davide Donadio, Giulia Galli. Ice nucleation at the nanoscale probes no man’s land of water. Nature Communications, 2013; 4: 1887 DOI: 10.1038/ncomms2918

Cite This Page:

George Washington University. "Better understanding of water's freezing behavior at nanoscale." ScienceDaily. ScienceDaily, 21 May 2013. <www.sciencedaily.com/releases/2013/05/130521152429.htm>.
George Washington University. (2013, May 21). Better understanding of water's freezing behavior at nanoscale. ScienceDaily. Retrieved April 21, 2014 from www.sciencedaily.com/releases/2013/05/130521152429.htm
George Washington University. "Better understanding of water's freezing behavior at nanoscale." ScienceDaily. www.sciencedaily.com/releases/2013/05/130521152429.htm (accessed April 21, 2014).

Share This



More Matter & Energy News

Monday, April 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Why Did Nike Fire Most Of Its Nike FuelBand Team?

Why Did Nike Fire Most Of Its Nike FuelBand Team?

Newsy (Apr. 19, 2014) Nike fired most of its Digital Sport hardware team, the group behind Nike's FuelBand device. Could Apple or an overcrowded market be behind layoffs? Video provided by Newsy
Powered by NewsLook.com
Small Reactors Could Be Future of Nuclear Energy

Small Reactors Could Be Future of Nuclear Energy

AP (Apr. 17, 2014) After the Fukushima nuclear disaster, the industry fell under intense scrutiny. Now, small underground nuclear power plants are being considered as the possible future of the nuclear energy. (April 17) Video provided by AP
Powered by NewsLook.com
Horseless Carriage Introduced at NY Auto Show

Horseless Carriage Introduced at NY Auto Show

AP (Apr. 17, 2014) An electric car that proponents hope will replace horse-drawn carriages in New York City has also been revealed at the auto show. (Apr. 17) Video provided by AP
Powered by NewsLook.com
Honda's New ASIMO Robot, More Human-Like Than Ever

Honda's New ASIMO Robot, More Human-Like Than Ever

AFP (Apr. 17, 2014) It walks and runs, even up and down stairs. It can open a bottle and serve a drink, and politely tries to shake hands with a stranger. Meet the latest ASIMO, Honda's humanoid robot. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins