Liu Yanmei, Bu Xiaohai, Liu Runqi, Feng Minxing, Zhang Zewu, Yuming Zhou
Jiangsu Optoelectronic Functional Materials Engineering Research Center, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
Jiangsu Optoelectronic Functional Materials Engineering Research Center, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China; School of Materials Science and Engineering, Nanjing Institute of Technology, Nanjing 211167, China.
Int J Biol Macromol. 2025 Mar;292:139239. doi: 10.1016/j.ijbiomac.2024.139239. Epub 2024 Dec 27.
Passive radiative cooling (PRC) is an emerging sustainable technology that plays a key role for achieving the goal of carbon neutrality. However, several challenges remain for PRC materials in their practical application in building thermal management, including overcooling problems and unsatisfactory cooling efficiency caused by solar absorption and parasitic heat gains. In this work, fluorinated cellulose-based composite aerogels (FCCA) integrating thermal insulation and PRC were developed by a facile manufacturing strategy that combined phase separation and freeze-drying. P(VdF-HFP) was utilized to promote the formation of nano/micro porous architectures in FCCA, resulting in a decrease in the thermal conductivity of the aerogel to 0.034 W m K while simultaneously increasing its solar reflectance and infrared emissivity (8-13 μm) to 95.74 % and 97.15 %, respectively. The aerogel cooler achieved a sub-ambient cooling temperature of ∼9.68 °C during the daytime and maintained its cooling effectiveness even on cloudy days. The fluorinated aerogels demonstrated excellent hydrophobicity and chemical durability after outdoor exposure and heat aging tests. This work opens up a new pathway to design low-cost cellulose-based materials for efficient thermal management of energy-saving buildings around the world.
被动辐射冷却（PRC）是一种新兴的可持续技术，对实现碳中和目标起着关键作用。然而，PRC材料在建筑热管理中的实际应用仍面临一些挑战，包括过冷问题以及由太阳能吸收和寄生热增益导致的冷却效率不理想。在这项工作中，通过相分离和冷冻干燥相结合的简便制造策略，开发了兼具隔热和PRC功能的氟化纤维素基复合气凝胶（FCCA）。利用聚（偏氟乙烯-六氟丙烯）（P(VdF-HFP)）促进FCCA中纳米/微孔结构的形成，使气凝胶的热导率降至0.034 W m⁻¹ K⁻¹，同时将其太阳能反射率和红外发射率（8 - 13μm）分别提高到95.74%和97.15%。该气凝胶冷却器在白天实现了约9.68°C的低于环境温度的冷却温度，即使在阴天也能保持其冷却效果。经过户外暴露和热老化测试后，氟化气凝胶表现出优异的疏水性和化学耐久性。这项工作为设计低成本纤维素基材料以实现全球节能建筑的高效热管理开辟了一条新途径。
