Daytime radiative cooling presents an exciting new strategy for combating global warming, because it can passively cool buildings by reflecting sunlight and utilizing the infrared atmospheric window to eject heat into outer space. Recent progress with novel material designs showed promising subambient cooling performance under direct sunlight. However, large-scale implementation of radiative cooling technologies is still limited by the high-cost and complex fabrication. Here, we develop a nanoporous polymer matrix composite (PMC) to enable rapid production and cost reduction using commercially available polymer processing techniques, such as molding, extrusion, and 3D printing. With a high solar reflectance of 96.2% and infrared emissivity > 90%, the nanoporous PMC achieved a subambient temperature drop of 6.1 °C and cooling power of 85 W/m² under direct sunlight, which are comparable to the state-of-the-art. This work offers great promise to make radiative cooling technologies more viable for saving energy and reducing emissions in building cooling applications.

中文翻译：

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用于白天辐射冷却的三维可印刷纳米多孔聚合物基复合材料

白天的辐射制冷提出了一种令人激动的新战略，以应对全球变暖，因为它可以通过反射太阳光并利用红外大气窗口将热量散发到外层空间来被动地为建筑物降温。新型材料设计的最新进展表明，在直射阳光下具有良好的低温冷却性能。但是，辐射冷却技术的大规模实施仍然受到高成本和复杂制造的限制。在这里，我们开发了一种纳米多孔聚合物基质复合材料（PMC），可以使用市售的聚合物加工技术（例如模塑，挤出和3D打印）快速生产并降低成本。纳米多孔PMC具有96.2％的高太阳反射率和90％的红外发射率，实现了6.1°C的低温降温和85 W / m的冷却功率²在直射阳光下，可与最新技术媲美。这项工作为使辐射制冷技术在建筑物制冷应用中节省能源和减少排放提供了更大的希望。