Enhancing Radiative Cooling for Aircraft and UAVs through Heterogeneous Bonding of Natural Mineral Sericite

Radiative cooling paints have been extensively researched for their ability to manage heat through passive cooling, which is beneficial for both spacecraft and aircraft. These coatings function by reflecting sunlight radiation and dissipating heat by infrared radiation, providing a cooling effect without the need for additional energy input. In this study, natural sericite was employed due to its high far-infrared emissivity. Silica (SiO2), alumina (Al2O3), and silica/alumina mixtures (SiO2/Al2O3) constituting the main components of sericite were used for comparison. The results show that the aluminum sheet with the coating of sericite and resin composite material had an excellent radiative cooling ability due to the presence of a large amount of Si-O-Al heterogeneous bonding in its interfaces of structures. The performance was better than that with the coating of its constituent materials, such as SiO2, Al2O3, or the mixture. The average daytime temperature under direct sunlight was 3.8°C lower than that of the control group resin alone aluminum sheet, and the cooling efficiency was as high as 9.8%. The temperature of each individual component in the evening was 2-2.5℃ lower than the surrounding air temperature, achieving the radiative cooling effect. Sericite displayed great potential as an excellent radiative cooling material for spacecraft and aircraft.