Having numerous glass surfaces in your home can make rooms feel bright and open, but they often bring in too much heat and expose you to prying eyes. A groundbreaking new metamaterial offers a solution by enhancing transparency, ensuring privacy, cooling interiors, and even cleaning itself. This innovation is known as the Polymer-based Micro-photonic Multi-functional Metamaterial (PMMM).

PMMM is a thin film that can be easily applied to standard glass. Its unique properties stem from the microscopic pyramid patterns etched on its surface, each just 10 microns wide. These tiny pyramids scatter 73% of incoming light, giving the material a frosted appearance while still allowing 95% light transmittance, compared to the 91% typical of regular glass. This feature ensures a brighter, more comfortable environment for both people and plants.

“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.”

One of PMMM’s most impressive features is its ability to perform radiative cooling. This phenomenon uses the Earth’s atmosphere, which is transparent to infrared wavelengths, to radiate heat directly into outer space. Tests demonstrated that PMMM could keep a room 6 °C (10.8 °F) cooler than the ambient air, reducing the need for air conditioning.

Additionally, PMMM is self-cleaning. The surface’s pyramid structure creates a superhydrophobic effect, causing water droplets to roll off, carrying away dust and dirt. This property is characterized by a contact angle of 152 degrees.

“The material can simultaneously optimize the use of sunlight indoors, provide passive cooling, and reduce reliance on air conditioning,” said Huang. “The solution is scalable and can be seamlessly integrated into plans for environmentally friendly building construction and urban development.”

PMMM represents a significant advancement in building materials, combining transparency, privacy, cooling, and cleanliness into a single, scalable solution. This metamaterial has the potential to revolutionize the way we think about glass in our homes and workplaces, offering a more sustainable and comfortable living environment.

By Impact Lab