Personal daytime radiative cooling (PDRC) materials have high sunlight reflection and high selective emissivity to outer space in the main atmospheric window, demonstrating huge potential in energy-saving for sustainable development. Recently, polymer-based membranes for radiative cooling have been widely reported, due to their easy processing, low cost, and unique optical performance. However, the desired high sunlight reflectance of PDRC materials is easily dampened by environmental aging, high temperature, and ultraviolet (UV) irradiation, resulting in reduced cooling performance for most polymers, adverse to large-scale practical applications. In this work, we demonstrate a novel polyimide nanofiber (PINF) membrane with a fluorine-containing structure via typical electrospinning technology. The resultant PINF membrane exhibits high sunlight reflectance, UV resistance, and excellent thermal stability, rendering anti-aging daytime radiative cooling. The sunlight reflectance of PINF membranes could maintain constant in the aging test for continuous 720 h under outdoor solar irradiation, exhibiting durable and long-term personal daytime radiative cooling performance.

个人日间辐射冷却（PDRC）材料在主要大气窗口中具有高太阳光反射率和对外层空间高选择性发射率，在节能可持续发展方面展现出巨大潜力。最近，用于辐射冷却的聚合物基膜因其易于加工、低成本和独特的光学性能而被广泛报道。然而，PDRC材料所需的高阳光反射率很容易受到环境老化、高温和紫外线（UV）照射的影响，导致大多数聚合物的冷却性能下降，不利于大规模实际应用。在这项工作中，我们通过典型的静电纺丝技术展示了一种具有含氟结构的新型聚酰亚胺纳米纤维（PINF）膜。所得的PINF膜具有高太阳光反射率、抗紫外线性和优异的热稳定性，可实现抗老化的日间辐射冷却。PINF膜在户外太阳照射下连续720小时的老化测试中阳光反射率保持恒定，表现出持久、长期的个人日间辐射制冷性能。