More transparent than glass, new material cools rooms and self-cleans

[Judi Lynn]

By Michael Irving
May 27, 2024



A sample of the new metamaterial, which is more transparent than glassGan Huang, KIT
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Having lots of glass surfaces can brighten up a room, but it also lets in too much heat as well as neighbors’ prying eyes. A new metamaterial is not only more transparent to light, but adds privacy, cools the room inside, and automatically cleans itself.

Known as a Polymer-based Micro-photonic Multi-functional Metamaterial (PMMM), the team’s creation takes the form of a thin film that can be stuck onto a pane of regular glass. It gets its special properties from the microscopic structure of its surface, which is etched with a pattern of pyramids each just 10 microns wide.

These mini-pyramids scatter 73% of the light that hits them, which gives the material that frosted look. But despite that, it’s surprisingly more transparent to light than regular glass – 95% transmittance compared to the usual 91% of most glass. The team says that makes for a more comfortable lighting not just for people, but plants as well.

“When the material is used in roofs and walls, it allows for bright yet glare-free and privacy-protected indoor spaces for work and living,” said Gan Huang, lead author of the study. “In greenhouses, the high light transmittance could increase yields because the photosynthesis efficiency is estimated to be 9% higher than in greenhouses with glass roofs.”

More:
https://newatlas.com/materials/metamaterial-glass-radiative-cooling-self-cleaning/