/   Home   /   Newsroom   /   Research News

【Nature】 Water-repellent Coatings Could Make De-icing a Breeze

Oct 12, 2017     Email"> PrintText Size

Coatings that force ice to grow upwards from the surface could make it easier to remove.

 

Wang et al., DOI 10.1073/pnas.1712829114

Ice growth on hydrophillic (top layer) and hydrophobic surfaces

When water droplets suspended in the air freeze, they generate snowflakes — ice crystals with six-fold symmetry. But when ice grows along a solid surface, like frost growing on windows, it can take on an almost infinite range of different shapes.

These crystalline patterns are affected by whether a surface repels or absorbs water, says a team led by chemists Jie Liu of the Chinese Academy of Sciences Institute of Chemistry in Beijing and Chongqin Zhu of the University of Nebraska–Lincoln. The researchers showed that when a surface tends to repel water, ice crystals can be cultivated to grow away from the surface at an angle, resembling a clover with six leaves.

The work was published on 9 October in the Proceedings of the National Academies of Science.

Clover crystals

Using a high-speed camera attached to a microscope, the team captured imagery of ice forming on aluminium that had been covered with a hydrophobic, or water-repellent, coating. Water drops sprayed on the surface remained taut and spherical instead of spreading out.

The researchers triggered ice formation across the entire surface by spraying it with silver iodide nanoparticles, which acted as seeds for ice growth. As the ice developed, the crystals grew outwards and up from the nanoparticle, forming a symmetrical, six-leafed clover with only a single point of contact with the surface.

On hydrophilic, or absorbant, surfaces, water spread out quickly, and so did ice — forming a sunflower-shaped crystal in full contact with the surface.

And, when the team prepared a hybrid surface with both hydrophilic and hydrophobic parts, ice spreading on the hydrophilic side came to a halt at the boundary with the hydrophobic side.

The researchers also observed that the clover-like ice crystals growing away from a hydrophobic surface could be removed by wind more easily than crystals on a hydrophilic surface.

For more details, please refer to http://www.nature.com/news/water-repellent-coatings-could-make-de-icing-a-breeze-1.22790.

Attachment:

(Editor: LIU Jia)

Contact

Institute of Chemistry

Phone:
E-mail:

Related Articles

ice;methane hydrate;nucleation;molecular dynamics

Researchers Reveal the Effects of Ice on Methane Hydrate Nucleation

Oct 12, 2017

The effect of ice on the nucleation of methane hydrate was investigated using microsecond constant energy molecular dynamics simulation by Prof. GUO Guangjun‘s lab at IGGCAS. They found that methane hydrate can nucleate either on the ice surface heterogeneously or in the...

Tibet;ice;glacier;avalanche

Researchers: Climate Change Likely Caused Deadly 2016 Avalanche in Tibet

Dec 26, 2016

With a deadly avalanche, it appears climate change may now be affecting a once stable region of the Tibetan Plateau. That’s the conclusion of an international team of researchers who have published an analysis of the July 2016 disaster in the Dec. 9 issue of the Journal ...

Contact Us

Copyright © 2002 - 2017 Chinese Academy of Sciences