EuroWire May 2020

Transatlantic cable

In a paper that appeared in the Cell Press journal Joule , the researchers described a coating for electronics that releases water vapour to dissipate heat from operating devices – a thermal management method that could prevent electronics from overheating, and keep them cooler than is currently possible. “The development of microelectronics puts great demands on e cient thermal management techniques, because all the components are tightly packed and chips can get really hot,” said senior author Ruzhu Wang, who studies refrigeration engineering at Shanghai Jiao Tong University. “For example, without an e ective cooling system our phones could have a system breakdown and burn our hands if we run them for a long time, or load a big application.” Larger devices, such as computers, use fans to regulate temperature, but fans are cumbersome, noisy and use energy, and so are unsuitable for smaller devices like mobile phones. Until now, manufacturers have used phase change materials (PCMs), such as waxes and fatty acids, for cooling in phones: as they melt, these materials absorb the heat produced by devices but the amount of energy exchanged during the solid-liquid transition is low. The liquid-vapour transition of water can exchange ten times more energy than the PCM solid-liquid transition. Mr Wang and his team studied a group of porous materials that can absorb moisture from the air and then release water vapour

a surface to print o nano-thin sheets. These 2D nano-sheets have the same chemical composition as standard ITO, but a di erent crystal structure that gives new mechanical and optical properties. As well as being fully exible, the new type of ITO absorbs just 0.7 per cent of light, compared with 5 to 10 per cent for standard conductive glass. It can be made more electronically conductive by adding more layers. According to Mr Daeneke, it’s a pioneering approach that overcomes a challenge once believed irresolvable: “There’s no other way of making this fully exible, conductive and transparent material, aside from our new liquid metal method,” he said. “It was impossible up to now – people just assumed that it couldn’t be done.” The research team has used its new material to create a working touchscreen, and has applied for a patent on the technology. The material could also be used in many other optoelectronic applications such as LEDs and touch displays, as well as in solar cells and smart windows. “We’re excited to be at the stage now where we can explore commercial collaboration opportunities, and work with the relevant industries to bring this technology to market,” Mr Daeneke said.

New coating keeps its cool

Researchers from China’s Shanghai Jiao Tong University are exploring whether phones could have a sweating mechanism, like mammals, in order to maintain their “body” temperature.

Advertise in this issue and be seen at...

September Issue 22 nd June 2020 Editorial closing date: 6 th July 2020 Advertising deadline date:

2020 Media Pack

28

www.read-eurowire.com

May 2020