Abstract Passive daytime radiative cooling plays a significant role in various cooling operations, which helps reducing electricity consumption and decreasing electricity demand. This work presents a new double-layered radiative cooling structure composed of a transparent dipentaerythritol penta-hexa-acrylate (DPHA) top layer, modified using Al2O3 nanoparticles (NPs) as resonators, and a metallic Ag bottom layer (DPHA@Al2O3 NPs/Ag). The DPHA@Al2O3 NPs layer is prepared through a fast photopolymerization process. The prepared DPHA@Al2O3 NPs/Ag system exhibits a solar reflectivity of 0.9465 and long-wave infrared (the so-called atmospheric transparency window) emissivity of 0.9163. The computed radiative cooling power at 27 °C can reach up to 106.43 W m−2. A subambient temperature drop of 10.35 °C is measured from 13:00 to 16:00 p.m. in Seoul, Korea, when using the proposed material as radiative cooler. Since this structure can be applied on flexible substrate, this has far-reaching implications for future applications in wearable devices.

中文翻译：

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丙烯酸膜掺杂 Al2O3 纳米粒子谐振器，用于零能耗辐射冷却

摘要 白天被动辐射冷却在各种冷却操作中发挥着重要作用，有助于减少电力消耗和减少电力需求。这项工作提出了一种新的双层辐射冷却结构，由透明的二季戊四醇五六丙烯酸酯 (DPHA) 顶层和金属 Ag 底层 (DPHA@Al2O3 NPs/Ag ）。DPHA@Al2O3 NPs 层是通过快速光聚合过程制备的。制备的 DPHA@Al2O3 NPs/Ag 系统的太阳反射率为 0.9465，长波红外（所谓的大气透明窗口）发射率为 0.9163。计算得出的 27 °C 辐射冷却功率可达 106.43 W m-2。在韩国首尔，从下午 13:00 到下午 16:00 测得的低于环境温度下降了 10.35 °C，当使用建议的材料作为辐射冷却器时。由于这种结构可以应用于柔性基板，这对未来可穿戴设备的应用具有深远的影响。