2025/09/12 by Song, Qimeng, Rettinger, Stefan, Xu, Chengzhang +2
#540 #biodegradable polymer #passive daytime cooling #radiative cooling #solar heating #solution blow spinning
paper · doi:10.15495/epub_ubt_00008553
Advanced thermal management is crucial in mitigating the escalating global energy consumption and alleviating associated climatic and environmental issues. Here, a dual-mode film that integrates solar heating and radiative cooling functionalities for year-round thermal management is introduced. The cooling side ofthe film, composed ofPCL-SiO2 composite nanofibers, exhibits an impressive solar reflection of0.98 and a mid-infrared emissivity of 0.91, resulting in sub-ambient cooling performance under intensive sunlight. Meanwhile, the heating side ofthe film, based on the ink side ofthe upcycled chip bags, efficiently harvests thermal energy from sunlight, leading to a temperature rise of16.5 °C. The cooling and heating modes ofthe film can be switched by flipping it. With its outstanding optical properties, weathering durability, and switchable heating and cooling modes, the dual-mode film holds great potential for year-round energy savings with minimal environmental impact due to its sustainable composition and easy fabrication.