Abstract：
Passive daytime radiative cooling (PDRC) technology offers a green and sustainable strategy for cooling, eliminating the need for external energy sources through its exceptional efficiency in heat radiation and sunlight reflection. Despite its benefits, the widespread usage of non-biodegradable PDRC materials has unfortunately caused environmental pollution and resource wastage. Furthermore, the effectiveness of outdoor PDRC materials can be significantly diminished by rainfall. In this work, a superhydrophobic composite aerogel composed of stereocomplex-type polylactide and ultra-fine glass fiber has been successfully developed through simple physical blending and freeze-drying, which exhibits low thermal conductivity (36.26 mW m-1 K-1) and superhydrophobicity (water contact angle up to 150°). Additionally, its high solar reflectance (91.68 %) and strong infrared emissivity (93.95 %) enable it to effectively lower surface temperatures during daytime, resulting in a cooling effect of approximately 3.8 °C below the ambient temperature during the midday heat of summer, with a cooling power of 68 W/m2. This aerogel offers an environmentally friendly and sustainable approach for the utilization of radiative refrigeration materials, paving the way for environmental protection and sustainable development.
摘要：
被动日间辐射冷却（PDRC）技术为冷却提供了绿色和可持续的策略，通过其在热辐射和阳光反射方面的卓越效率，消除了对外部能源的需求。尽管有好处,不可生物降解的PDRC材料的广泛使用已经造成了环境污染和资源浪费。此外，室外PDRC材料的有效性会因降雨而大大降低。在这项工作中,通过简单的物理共混和冷冻干燥，成功开发了由立体络合物型聚乳酸和超细玻璃纤维组成的超疏水复合气凝胶，具有低热导率（36.26mWm-1K-1）和超疏水性（水接触角高达150°）。此外,其高太阳反射率（91.68％）和强红外发射率（93.95％）使其能够有效降低白天的表面温度，在夏季中午高温期间，产生比环境温度低大约3.8°C的冷却效果，具有68W/m2的冷却功率。这种气凝胶为辐射制冷材料的利用提供了一种环保和可持续的方法，为环境保护和可持续发展铺平道路。
