Maximizing natural light in buildings is a popular trend that can help save on energy costs, but traditional glass components like roofs and walls can present issues such as glare, lack of privacy, and overheating. Solutions like coatings and light-diffusing materials have not been able to fully address these concerns. However, researchers at the Institute for Microstructure Technology (IMT) and the Light Technology Institute (LTI) at KIT have developed a novel polymer-based metamaterial that could potentially replace glass components in construction in the future.
The Polymer-based Micro-Photonic Multi-Functional Metamaterial (PMMM) consists of microscopic pyramids made of silicone, each measuring about ten micrometers in diameter. This design allows the PMMM film to have multiple functions, including light diffusion, self-cleaning, and radiative cooling while maintaining a high level of transparency. The material is able to efficiently radiate heat through the Earth’s atmosphere’s long-wave infrared transmission window, resulting in passive radiative cooling without electricity consumption.
In experiments under real outdoor conditions, the researchers tested the material’s properties and found that it achieved cooling of 6 °C compared to the ambient temperature. The material also exhibited a high spectral transparency of 95 percent and scattered 73 percent of incoming sunlight, resulting in a bright yet glare-free and privacy-protected indoor space. The superhydrophobic properties of the micro-pyramids make the material self-cleaning, similar to a lotus leaf, allowing dirt and dust to be easily removed from the surface.
The potential applications of this new material in construction and urban development are vast. It has the ability to optimize sunlight indoors, provide passive cooling, and reduce reliance on air conditioning, making it a sustainable and energy-efficient option for architecture. The material can be seamlessly integrated into plans for environmentally friendly building construction and urban development, offering a scalable solution that can contribute to a more sustainable future.
Overall, this novel polymer-based metamaterial offers a promising solution to the challenges presented by traditional glass components in buildings. With its multiple functions, including light diffusion, self-cleaning, and radiative cooling, the PMMM material has the potential to revolutionize the way natural light is utilized in construction while also contributing to energy efficiency and sustainability. Its scalability and versatility make it a valuable addition to the toolkit of architects and urban developers looking to create environmentally friendly and efficient buildings.