Researchers at the Karlsruher Institut für Technologien (KIT) have recently developed a new material that is both self-cleaning and energy-efficient, with the goal of replacing glass commonly used in construction. The material, called polymer-based micro-photonic multi-functional metamaterial (PMMM), has been tested and found to cool the area by six degrees Celsius compared to the outside temperature, while still maintaining a transparency level of 95 percent – higher than standard glass which typically has a transparency of 91 percent.
The use of glass in construction has been increasing in recent years due to its ability to allow natural light in and potentially save on energy costs. However, conventional glass materials can cause issues such as glare, lack of privacy, and excessive heat during sunny periods of the day. Current glass coatings have not been able to fully address these problems, prompting researchers at KIT to develop this innovative material.
PMMM is made up of tiny pyramids made of silicone, each about ten micrometers in size. These micro-pyramids scatter light, giving the material a fuzzy appearance from the outside. Additionally, the pyramids increase the material’s water-repellent properties, much like a lotus leaf, allowing it to self-clean as water washes away dirt with it. The designed material has the ability to increase light diffusion, clean itself, and cool by radiation without the need for electricity consumption. Tests using a spectrophotometer to measure light transmission, scattering, reflection, and cooling power have shown promising results. The researchers believe that this material can not only optimize sunlight usage indoors, but also offer passive cooling and a reduction in the need for air conditioning.
The production of PMMM is considered scalable and it has the potential to be integrated into environmentally friendly house construction practices
