A solution-processed radiative cooling glass

Area of Science:

• Materials Science
• Nanotechnology
• Sustainable Energy

Background:

• Passive daytime radiative cooling (PDRC) materials reduce building energy consumption by reflecting sunlight and emitting long-wave infrared (LWIR) radiation.
• Developing PDRC structures with manufacturing practicality, applicability, and long-term environmental stability remains a challenge.

Purpose of the Study:

• To develop a novel passive cooling material with enhanced performance and durability.
• To address the limitations of existing PDRC technologies.

Main Methods:

• Fabrication of a randomized photonic composite using a microporous glass framework and aluminum oxide particles.
• Characterization of the material's optical properties (solar reflectance and LWIR emissivity).
• Testing of the material's cooling performance under various environmental conditions, including high humidity, water exposure, UV radiation, soiling, and high temperatures.

Main Results:

• The developed microporous glass coating exhibits selective LWIR emission and high solar reflectance.
• Achieved a temperature drop of approximately 3.5°C during midday and 4°C during nighttime, even under 80% humidity.
• The radiative cooling glass coating demonstrated sustained high solar reflectance after exposure to harsh conditions.

Conclusions:

• The novel microporous glass composite is a practical and stable solution for passive daytime radiative cooling.
• This technology offers a promising pathway to significantly reduce building cooling energy demands.
• The material's resilience to environmental factors ensures long-term effectiveness for sustainable cooling applications.