Molecularly and Structurally Designed Polyimide Nanofiber Radiative Cooling Films for Spacecraft Thermal Management

摘要

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.

宋效坤

PhD

张漫遥

PhD

赵其斌

副教授

我的研究关注软功能材料中的介观结构调控及其光学、热学与力学功能。我们以胶体、颗粒组装和聚合物复合体系为主要材料平台，研究剪切、弯曲、拉伸和循环形变等外部力学场如何驱动微结构重排、结晶、晶格转变与取向选择，并进一步调控材料的结构色、光谱响应、热辐射特性和力学响应。通过将软物质物理、可规模化加工和结构—性能分析相结合，研究旨在发展可编程软光子材料与功能涂层，为自适应光学表面、光热调控、传感和机械编码材料提供新的设计思路.