Radiative cooling and evaporative cooling with low carbon footprint are regarded as promising passive cooling strategies. However, the intrinsic limits of continuous water supply with complex systems for evaporative cooling, and restricted cooling power as well as the strict requirement of weather conditions for radiative cooling, hinder the scale of their practical applications. Here, we propose a tandem passive cooler composed of bilayer polymer that enables dual-functional passive cooling of radiation and evaporation. Specifically, the high reflectivity to sunlight and mid-infrared emissivity of this polymer film allows excellent radiative cooling performance, and its good atmospheric water harvesting property of underlayer ensures self-supply of water and high evaporative cooling power. Consequently, this tandem passive cooler overcomes the fundamental difficulties of radiative cooling and evaporative cooling and shows the applicability under various conditions of weather/climate. It is expected that this design can expand the practical application domain of passive cooling.

中文翻译：

---

一种串联辐射/蒸发冷却器，适用于不受天气影响的高性能日间被动冷却

具有低碳足迹的辐射冷却和蒸发冷却被认为是有前途的被动冷却策略。然而，蒸发冷却系统复杂的连续供水的内在限制、冷却功率受限以及辐射冷却对天气条件的严格要求，阻碍了其实际应用的规模。在这里，我们提出了一种由双层聚合物组成的串联被动冷却器，可以实现辐射和蒸发的双重功能被动冷却。具体来说，这种聚合物薄膜对太阳光的高反射率和中红外发射率使其具有出色的辐射冷却性能，其底层良好的大气集水性能确保了水的自给和高蒸发冷却能力。最后，这种串联被动冷却器克服了辐射冷却和蒸发冷却的根本困难，并显示出在各种天气/气候条件下的适用性。预计这种设计可以扩大被动冷却的实际应用领域。