We love cars here at Digital Trends, but we don’t love everything about them. Something that is right at the top of every car owner’s list of things they despise about car ownership? Defrosting a vehicle’s windows on cold winter mornings.
Fortunately, researchers from ETH Zurich in Switzerland are on the case — and their solution involves some pretty darn cool tech. What they have developed is a solar-activated nanoscale-thick coating consisting of two different materials, gold and titanium dioxide. Together, these materials have a unique sunlight-absorbing property, rendering them capable of defrosting frozen windows rapidly. The combined material can do this without affecting the transparency of the glass in the windows.
“Our so-called ‘metasurafaces’ can inhibit or remove frost by absorbing sunlight, a renewable energy source, and heating,” Efstratios Mitridis, a Ph.D. candidate in the Laboratory of Thermodynamics in Emerging Technologies, told Digital Trends. “By tuning the coating thickness, we can render them transparent at the same time. These metasurfaces can be deposited on a variety of commercially important substrates, including glass and acrylics. Balancing transparency and absorption is the key to effective icing prevention and deicing for applications requiring visibility.”
The researchers have so far tested their ultra-thin absorbent nanocoating on commercial materials. However, Hadi Eghlidi, another researcher on the project, told us that commercializing the coating will pose additional challenges going forward. “[This will require] large-scale and cost-effective fabrication of the coating, a milestone which we are currently working hard to achieve,” Eghlidi said. “In parallel, we are working on new designs and materials to improve the performance of the coating — for example, to achieve more transparency or a higher temperature increase.”
ETH Zurich isn’t the only research lab working on a solution to this problem. Last year, we wrote about another innovative research project coming out of Virginia Tech University, where investigators developed a special water-repellent aluminum surface that traps millions of tiny air pockets underneath a sheet of frost growing on the surface. This also speeds up the rate of thawing significantly.
A paper describing the new ETH Zurich work, titled “Metasurfaces Leveraging Solar Energy for Icephobicity,” was recently published in the journal ACS Nano.