Highly Efficient and Environmentally Stable Radiative Cooling Fabric: Integrating Photoluminescence and Hierarchical Core–Shell Fibers

ABSTRACT Polymer‐based radiative coolers are promising for zero‐energy heat management due to their flexibility and processability. However, their cooling performance and outdoor durability must be enhanced, specifically in weatherability, mechanical robustness, and anti‐fouling properties. Here, we demonstrate a scalable radiative cooling polymer fabric based on a multi‐layer assembly structure and photoluminescent material integration. This fabric exhibits high radiative cooling efficiency and notable environmental stability, demonstrating its potential as a candidate material for applications in energy‐efficient building cooling and personal thermal management. The hierarchical core–shell architecture synergizes with photon‐manipulating photoluminescence to optimize solar radiation blocking and thermal re‐emission, achieving a remarkable effective solar reflectivity (ESR, 101.1%) in the specific spectral band. Combined with its exceptional average mid‐infrared emissivity (95.34%), our multi‐layer core–shell radiative cooling fabric (Mc‐sRCF) delivers a maximum daytime sub‐ambient cooling of 10.0 °C under Beijing summer conditions (peak solar intensity of 858 W·m ^{− 2} ) while providing a cooling power contribution of 83.78 W·m ^{− 2} . Notably, the multi‐level fiber architecture, synergistically integrated with stable chemical bonds on the outer layer and embedded multi‐scale nanoparticles (TiO ₂ ), endows the fabric with superior mechanical robustness (tensile strength: 8.7 MPa), long‐term UV resistance, rainproof/anti‐fouling properties, and self‐extinguishing flame retardancy, offering a promising pathway for durable outdoor applications.