Photoluminescent Core–Shell Structural Porous Fibers-Based Metafabric for Colored Daytime Passive Radiative Cooling

Passive radiative cooling technology provides a sustainable thermal management strategy for outdoor workers under extremely hot environments. However, daytime radiative cooling textiles typically appear white or mirror-like due to the near-complete reflection of sunlight, which poses a significant limitation for outdoor applications where visual aesthetics are important. Herein, we designed colored photoluminescent radiative cooling (CPRC) metafabrics, which are woven from carbon-dot-based coaxial porous fibers, to achieve effective radiative cooling without sacrificing color aesthetics. The coaxial porous fibers are designed with a nanostructured light-scattering shell layer and an enhanced mid-infrared emission core layer, which together improve sunlight reflection and human infrared thermal radiation. Leveraging the photoluminescent properties of carbon dots, the CPRC metafabrics enable selective adsorption of visible light to display vivid colors while re-emitting photons to reduce solar heat generation, achieving a high light-to-photon conversion efficiency of 48.3%. Consequently, the CPRC metafabric with its colorful appearance demonstrates a maximum net cooling power of 69.2 W m^–2, offering average cooling temperatures that are 3.7 and 3.6 °C lower than those of colored commercial wool and dye-based fabric, respectively. Furthermore, the CPRC metafabrics possess self-sensing health monitoring capability and long-time durability, ensuring both safety and thermal comfort for outdoor workers. This work effectively addresses the long-standing problem of integrating color aesthetics with daytime radiative cooling textiles, facilitating the development and application of next-generation wearable energy-saving textiles.