Scalable and Healable Gradient Textiles for Multi-Scenario Radiative Cooling via Bicomponent Blow Spinning.

Radiative cooling textiles with spectrally selective surfaces offer a promising energy-efficient approach for sub-ambient cooling of outdoor objects and individuals. However, the spectrally selective mid-infrared emission of these textiles significantly hinders their efficient radiative heat exchange with self-heated objects, thereby posing a significant challenge to their versatile cooling applicability. Herein, we present a bicomponent blow spinning strategy for the production of scalable, ultra-flexible, and healable textiles featuring a tailored dual gradient in both chemical composition and fiber diameter. The gradient in the fiber diameter of this textile introduces a hierarchically porous structure across the sunlight incident area, thereby achieving a competitive solar reflectivity of 98.7% on its outer surface. Additionally, the gradient in the chemical composition of this textile contributes to the formation of Janus infrared-absorbing surfaces: The outer surface demonstrates a high mid-infrared emission, whereas the inner surface shows a broad infrared absorptivity, facilitating radiative heat exchange with underlying self-heated objects. Consequently, this textile demonstrates multi-scenario radiative cooling capabilities, enabling versatile outdoor cooling for unheated objects by 7.8 °C and self-heated objects by 13.6 °C, compared to commercial sunshade fabrics.