Biopolymer-Based Sustainable Asymmetric Fiber Membrane with Radiative Cooling and Heating for Thermal Management

Passive radiative cooling and heating technologies have garnered significant attention in both the academic and industrial communities as sustainable alternatives to conventional energy-intensive thermal management approaches. Significant advances have been achieved in textiles with dual passive radiative cooling and heating capabilities. However, current designs remain static in configuration, exhibiting inadequate adaptability to seasonal weather variations. Herein, we propose a dual-mode operational mechanism enabling all-day passive radiative cooling and heating. An asymmetric PLA/PBS/TiO2-MXene composite fiber membrane with dual-sided thermal management capabilities was fabricated via the integration of electrospun PLA/PBS/TiO2 fiber membrane and MXene coatings. A layered architecture was engineered to establish differential emissivity on opposing sides of a fiber membrane substrate, thereby enabling rapid switching between radiative cooling and heating functionalities. During outdoor thermal testing, the dual-sided fiber membrane demonstrated efficient passive radiative cooling and heating capabilities. The cooling side achieved temperature reductions of 4.1–10.0 °C, while the heating side attained temperature increases of 11.8–18.1 °C, under solar irradiance of 831.4–1057 W/m2. In addition, the asymmetric fiber membrane demonstrated decent chemical recyclability, providing a way for developing sustainable cooling/heating materials.