Nanotechnology and sunlight clear the way for better visibility
by Staff Writers
Zurich, Switzerland (SPX) Mar 06, 2019
Anyone who skis, wears glasses, uses a camera or drives a car is familiar with the problem: if you come into a humid environment from the cold, your eyewear, camera lens or windshield can quickly fog up.
Researchers at ETH Zurich have now developed a new transparent material coating that greatly reduces this effect. Just a few nanometres thick, their durable coating is made of gold nanoparticles embedded in non-conductive titanium oxide.
"Our coating absorbs the infrared component of sunlight along with a small part of the visible sunlight and converts the light into heat," explains Christopher Walker, a doctoral student in ETH Professor Dimos Poulikakos's group and lead author of the study. This heats the surface up by 3 to 4 degrees Celsius. It is this difference in temperature that prevents fogging.
But unlike these methods, the ETH researchers' new coating works passively. Since the only energy source required is the sun, their coating is especially suitable for wearable items such as glasses and goggles.
Efstratios Mitridis, another doctoral student in Poulikakos's group, explains what makes the new surface coating so special: "Normally, it's dark surfaces that absorb light and convert it into heat," he says, "but we've created a transparent surface that has the same effect."
Better than anti-fog sprays
As an alternative to using heat to prevent fogging, susceptible surfaces can be coated with hydrophilic agents. Because they attract water, these agents ensure that the condensation forms an even thin film of liquid over the surface rather than separate droplets. Anti-fog sprays for glasses usually work on this principle.
Now, tests have shown that when exposed to sunlight, fogged surfaces coated with gold nanoparticles and titanium oxide clear four times faster than surfaces treated with a normal anti-fog agent.
"Spray treatments often lose their effect after a while because the anti-fog film dries up or becomes unevenly distributed," Walker says. "A durable coating like ours lasts much longer than a spray treatment, which you have to apply virtually on a daily basis," he adds.
The ETH scientists are now planning to bring their new method to market, in collaboration with a partner from industry. "We're looking to refine our already robust coating to ensure it lasts for years, and we want to take the technology from lab scale to industry scale," Walker says.
Their coating has a huge range of potential applications, including car windshields and rear-view mirrors as well as ski goggles and diving masks.
Research Report: "Metasurfaces Counteracting Fogging by Harnessing Sunlight"
Good news for future tech: Exotic 'topological' materials are surprisingly common
Princeton NJ (SPX) Mar 04, 2019
In a major step forward for an area of research that earned the 2016 Nobel Prize in Physics, an international team has found that substances with exotic electronic behaviors called topological materials are in fact quite common, and include everyday elements such as arsenic and gold. The team created an online catalog to make it easy to design new topological materials using elements from the periodic table. These materials have unexpected and strange properties that have shifted scientists' under ... read more
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.