Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Breaking the ice before it begins

Ice accumulation on flat aluminum (A), smooth fluorinated Si (B), and microstructured fluorinated Si (C) surfaces.
Ice accumulation on flat aluminum (A), smooth fluorinated Si (B), and microstructured fluorinated Si (C) surfaces.

Abstract:
Nanostructured materials repel water droplets before they have a chance to freeze

Breaking the ice before it begins

Cambridge, MA | Posted on November 15th, 2010

Engineers from Harvard University have designed and demonstrated ice-free nanostructured materials that literally repel water droplets before they even have the chance to freeze.

The finding, reported online in ACS Nano on November 9th, could lead to a new way to keep airplane wings, buildings, powerlines, and even entire highways free of ice during the worst winter weather. Moreover, integrating anti-ice technology right into a material is more efficient and sustainable than conventional solutions like chemical sprays, salt, and heating.

A team led by Joanna Aizenberg, Amy Smith Berylson Professor of Materials Science at the Harvard School of Engineering and Applied Sciences (SEAS) and a Core Member of the Wyss Institute for Biologically Inspired Engineering at Harvard, focused on preventing rather than fighting ice buildup.

"We wanted to take a completely different tact and design materials that inherently prevent ice formation by repelling the water droplets," says Aizenberg. "From past studies, we also realized that the formation of ice is not a static event. The crucial approach was to investigate the entire dynamic process of how droplets impact and freeze on a supercooled surface."

For initial inspiration, the researchers turned to some elegant solutions seen in nature. For example, mosquitos can defog their eyes, and water striders can keep their legs dry thanks to an array of tiny bristles that repel droplets by reducing the surface area each one encounters.

"Freezing starts with droplets colliding with a surface," explains Aizenberg. "But very little is known about what happens when droplets hit surfaces at low temperatures."

To gain a detailed understanding of the process, the researchers watched high-speed videos of supercooled droplets hitting surfaces that were modeled after those found in nature. They saw that when a cold droplet hits the nanostructured surface, it first spreads out, but then the process runs in reverse: the droplet retracts to a spherical shape and bounces back off the surface before ever having a chance to freeze.

By contrast, on a smooth surface without the structured properties, a droplet remains spread out and eventually freezes.

"We fabricated surfaces with various geometries and feature sizes—bristles, blades, and interconnected patterns such as honeycombs and bricks—to test and understand parameters critical for optimization," says Lidiya Mishchenko, a graduate student in Aizenberg's lab and first author of the paper.

The use of such precisely engineered materials enabled the researchers to model the dynamic behavior of impacting droplets at an amazing level of detail, leading them to create a better design for ice-preventing materials.

Another important benefit of testing a wide variety of structures, Mishchenko adds, was that it allowed the team to optimize for pressure-stability. They discovered that the structures composed of interconnected patterns were ideally suited for stable, liquid-repelling surfaces that can withstand high-impact droplet collisions, such as those encountered in driving rain or by planes in flight.

The nanostructured materials prevent the formation of ice even down to temperatures as low as -25 to -30 degrees Celsius. Below that, due to the reduced contact area that prevents the droplets from fully wetting the surface, any ice that forms does not adhere well and is much easier to remove than the stubborn sheets that can form on flat surfaces.

"We see this approach as a radical and much needed shift in anti-ice technologies," says Aizenberg. "The concept of friction-free surfaces that deflect supercooled water droplets before ice nucleation can even occur is more than just a theory or a proof-of-principle experiments. We have begun to test this promising technology in real-world settings to provide a comprehensive framework for optimizing these robust ice-free surfaces for a wide range of applications, each of which may have a specific set of performance requirements."

In comparison with traditional ice prevention or removal methods like salting or heating, the nanostructured materials approach is efficient, non-toxic, and environmentally friendly. Further, when chemicals are used to de-ice a plane, for example, they can be washed away into the environment and their disposal must be carefully monitored. Similarly, salt on roads can lead to corrosion and run-off problems in local water sources.

The researchers anticipate that with their improved understanding of the ice forming process, a new type of coating integrated directly into a variety of materials could soon be developed and commercialized.

In addition to Aizenberg, who is also the Susan S. and Kenneth L. Wallach Professor at the Radcliffe Institute for Advanced Study and a Professor of Chemistry and Chemical Biology at Harvard, and Mishchenko, the co-authors of the paper included Benjamin Hatton and Vaibhav Bahadur, both at SEAS and Wyss, and Ashley Taylor and Tom Krupenkin, both at the University of Wisconsin-Madison.

The researchers acknowledge L. Stirling and A. Grinthal for their valuable contribution and funding from DARPA (Award Number HR0011-08-C-0114); the Wyss Institute for Biologically Inspired Engineering at Harvard University; and the U.S. Department of Homeland Security (DHS) Scholarship and Fellowship Program.

####

For more information, please click here

Contacts:
Michael Patrick Rutter
617-496-3815

Copyright © Harvard University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

National Conference on Nanomaterials, (NCN-2017) April 21st, 2017

NanoMONITOR shares its latest developments concerning the NanoMONITOR Software and the Monitoring stations April 21st, 2017

Nanomechanics, Inc. Unveils New Product at ICMCTF Show April 25th: Nanoindentation experts will launch the new Gemini that measures the interaction of two objects that are sliding across each other – not merely making contact April 21st, 2017

Possible Futures

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

Rice crew revved for Nanocar Race: Nanocar creator James Tour and team take on international competition with single-molecule marvel April 20th, 2017

Making Batteries From Waste Glass Bottles: UCR researchers are turning glass bottles into high performance lithium-ion batteries for electric vehicles and personal electronics April 19th, 2017

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Academic/Education

SUNY Polytechnic Institute Announces Total of 172 Teams Selected to Compete in Solar in Your Community Challenge: Teams from 40 states, plus Washington, DC, 2 Territories, and 4 American Indian Reservations, Will Deploy Solar in Underserved Communities April 20th, 2017

Rice crew revved for Nanocar Race: Nanocar creator James Tour and team take on international competition with single-molecule marvel April 20th, 2017

The Catholic University of Rome uses the JPK NanoWizard® AFM & CellHesion® systems to understand how cells sense and respond to mechanical stimuli April 5th, 2017

AIM Photonics Welcomes Coventor as Newest Member: US-Backed Initiative Taps Process Modeling Specialist to Enable Manufacturing of High-Yield, High-Performance Integrated Photonic Designs March 16th, 2017

Discoveries

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

Wood filter removes toxic dye from water April 21st, 2017

Rice crew revved for Nanocar Race: Nanocar creator James Tour and team take on international competition with single-molecule marvel April 20th, 2017

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Materials/Metamaterials

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

National Conference on Nanomaterials, (NCN-2017) April 21st, 2017

Forge Nano 2017: 1st Quarter Media Update April 20th, 2017

Making Batteries From Waste Glass Bottles: UCR researchers are turning glass bottles into high performance lithium-ion batteries for electric vehicles and personal electronics April 19th, 2017

Announcements

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

National Conference on Nanomaterials, (NCN-2017) April 21st, 2017

NanoMONITOR shares its latest developments concerning the NanoMONITOR Software and the Monitoring stations April 21st, 2017

Nanomechanics, Inc. Unveils New Product at ICMCTF Show April 25th: Nanoindentation experts will launch the new Gemini that measures the interaction of two objects that are sliding across each other – not merely making contact April 21st, 2017

Automotive/Transportation

Making Batteries From Waste Glass Bottles: UCR researchers are turning glass bottles into high performance lithium-ion batteries for electric vehicles and personal electronics April 19th, 2017

BASF and Landa partner to create revolutionary pigments for automotive coatings: The alliance combines BASF innovations with Landa nano-pigment technology April 5th, 2017

ATTOPSEMI Technology Joins FDXcelerator Program to Deliver Advanced Non-Volatile Memory IP to GLOBALFOUNDRIES 22 FDX® Technology Platform: Leading-edge I-fuse™ brings higher reliability, smaller cell size and ease of programmability for consumer, automotive, and IoT applications March 27th, 2017

Promising results obtained with a new electrocatalyst that reduces the need for platinum: Researchers from Aalto University have succeeded in manufacturing electrocatalysts used for storing electric energy with one-hundredth of the amount of platinum that is usually needed March 24th, 2017

Home

Rice lab expands palette for color-changing glass: Nanophotonics team creates low-voltage, multicolor, electrochromic glass March 8th, 2017

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

Industrial Nanotech, Inc. Announces Plans to Spin Off New Product Line to Major Paint Compan November 9th, 2016

New flexible material can make any window 'smart' August 23rd, 2016

Aerospace/Space

Space energy technology restored to make power stations more efficient: Scientists use graphene to reinvent abandoned heat energy converter technology March 7th, 2017

Applied Graphene Materials plc - Significant commercial progress in AGM’s three core sectors March 3rd, 2017

Triboelectric Nanogenerators Boost Mass Spectrometry Performance March 1st, 2017

EmTech Asia breaks new barriers with potential applications of space exploration with NASA and MIT February 22nd, 2017

Industrial

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Rare-earths become water-repellent only as they age March 22nd, 2017

CRMGroup in Belgium uses a Deben three point bending stage in the development of new steel & coated steel products for automotive and other industrial applications March 21st, 2017

Imaging the inner workings of a sodium-metal sulfide battery for first time: Understanding how the structural and chemical makeup of the material changes during the charge/discharge process could help scientists advance battery design for future energy storage needs March 9th, 2017

Construction

Next-gen steel under the microscope March 18th, 2017

Graphene foam gets big and tough: Rice University's nanotube-reinforced material can be shaped, is highly conductive February 13th, 2017

New low-cost technique converts bulk alloys to oxide nanowires January 24th, 2017

Rice U probes ways to turn cement's weakness to strength: Rice University lab's calculations show new mechanisms to induce strength, ductility into concrete January 6th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project