Daytime Radiative Cooling Using Near-Black Infrared Emitters
Daytime Radiative Cooling Using Near-Black Infrared Emitters
复制标题
DOI：
10.1021/acsphotonics.6b00991
复制
发表时间：
2017-03-01
期刊：
影响因子：
7
通讯作者：
Minnich, Austin J.
中科院分区：
文献类型：
--
作者：
Kou, Jun-Long;Jurado, Zoila;Minnich, Austin J.
最近的研究表明，利用设计成在红外大气透明窗口发射的多层薄膜，在反射可见光的同时，可以实现日间直射阳光下的辐射冷却。在这里，我们证明了聚合物镀膜熔融二氧化硅反射镜作为中红外和太阳光谱中近理想反射器的近理想黑体，在阳光直射(8.2摄氏度)和夜间(8.4摄氏度)下实现了低于环境空气温度的辐射制冷。此外，我们估计，即使考虑外部传导和对流的显著影响，该制冷器在环境温度下的白天平均净制冷功率约为127W m(-2)，是以前报道的两倍多。我们的工作表明，丰富的材料和直接的制造可以用来实现白天的辐射冷却，促进了诸如火力发电厂的干冷却等应用。
Recent works have demonstrated that daytime radiative cooling under direct sunlight can be achieved using multilayer thin films designed to emit in the infrared atmospheric transparency window while reflecting visible light. Here, we demonstrate that a polymer-coated fused silica mirror, as a near-ideal blackbody in the mid-infrared and near-ideal reflector in the solar spectrum, achieves radiative cooling below ambient air temperature under direct sunlight (8.2 degrees C) and at night (8.4 degrees C). Its performance exceeds that of a multilayer thin film stack fabricated using vacuum deposition methods by nearly 3 degrees C. Furthermore, we estimate the cooler has an average net cooling power of about 127 W m(-2) during daytime at ambient temperature even considering the significant influence of external conduction and convection, more than twice that reported previously. Our work demonstrates that abundant materials and straightforward fabrication can be used to achieve daytime radiative cooling, advancing applications such as dry cooling of thermal power plants.