Molecularly and Structurally Designed Polyimide Nanofiber Radiative Cooling Films for Spacecraft Thermal Management
Abstract
Radiative cooling films (RCFs) are crucial for spacecraft thermal management, but their optical performance is currently limited by their structures and intrinsic high absorption at short wavelengths. In this study, a novel RCF using electrospun polyimide nanofibers optimized at both the molecular and microscale levels is developed. The newly designed polyimide molecules significantly decrease visible and ultraviolet (UV) light absorption while maintaining excellent thermal radiation properties in the infrared spectrum. By optimizing the diameter and orientation of the nanofibers using Monte Carlo simulations, the resulting film achieves a solar reflectivity of 99.6% and a mid‐infrared emissivity of 0.93. Its physical structures and optical properties remain stable under exposure to UV light, atomic oxygen, and extreme temperature changes. Further vacuum radiative cooling tests reveal that the thermal equilibrium temperature of this film is approximately 28 °C lower than that of Kapton‐based RCFs currently used in spacecraft. These results provide a new approach for creating efficient thermal management materials for space applications, with potential for broader use in architecture, electronic devices, and outdoor equipment.
Xiaokun Song
PhD
Manyao Zhang
PhD
Qibin Zhao
Associate Professor
My research focuses on soft functional materials in which mesoscale structure controls optical and physical properties. I have worked extensively on colloidal and particle-assembled photonic materials, developing scalable processing methods to organize soft particulate systems into structurally coloured films and coatings. A central theme of my work is how external mechanical fields, such as shear, bending, stretching, and cyclic deformation, can drive microstructural ordering, lattice transitions, and structure-dependent optical responses. More broadly, I am interested in programmable soft photonic materials and functional coatings, where colloidal assembly, deformation processing, and soft-matter physics can be used to create adaptive optical, thermal, sensing, or mechanically encoded material functions.