A Robust Radiative Cooling Fabric with Superior UV Stability via Synergistic Pore and Nanoparticle Shielding

Polymer-based radiative cooling materials combine flexibility with zero-energy cooling capabilities, offering promising solutions for advanced thermal management textiles in high-temperature environments. However, prolonged exposure to ultraviolet (UV) radiation triggers photodegradation, leading to yellowing and a consequent reduction in cooling performance. This study proposes a fabrication strategy for a flexible cooling textile based on a triband optical response. A hierarchically porous micronano membrane is designed to minimize solar heating by reflecting sunlight and simultaneously facilitate heat dissipation through strong mid-infrared emission. Concurrently, zinc oxide nanoparticles are incorporated to achieve efficient UV shielding. Due to the synergistic UV shielding between nanoparticles and the porous matrix, the fabric achieves outstanding radiative cooling (95% solar reflectance, 92% mid-IR emissivity) with a remarkably low ZnO loading of only 0.5%. This approach effectively avoids the discoloration and stiffening of the membrane typically caused by high filler concentrations in conventional methods, while additionally enhancing breathability and reducing cost. Outdoor tests demonstrate that the fabric achieves a subambient cooling effect of 5.6 °C and exhibits an exceptional Ultraviolet Protection Factor (UPF ≈2000). Furthermore, it maintains highly efficient cooling performance even after 400 h of UV exposure. The fabric's enhanced mechanical strength, water resistance, and breathability work synergistically to ensure durability and provide comprehensive protection for the wearer. This cost-effective, scalable, and durable radiative cooling textile thus holds significant potential for applications in healthcare, outdoor labor, and defense.