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Updated: Jun 13, 2025

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通过结晶性改变等级化微型和纳米结构聚合物,以实现可持续的环境冷却

Changmin Shi¹, Seung-Hyun Kim¹, Natalie Warren²

¹School of Engineering, Brown University, Providence, Rhode Island 02912, United States of America.

Langmuir : the ACS journal of surfaces and colloids

|September 9, 2024

概括

这项研究介绍了一种新型,薄型的被动日间辐射冷却器 (PDRC),由聚乙烯化物-三乙烯制成. 这种经济的材料提供了显著的冷却潜力和节能,减少了对传统空调的依赖.

科学领域:

材料科学材料科学材料科学
可持续能源可持续能源
纳米技术纳米技术

背景情况:

传统的空调消耗大量的电力,并使用有害化学物质,如,有助于臭氧层的消耗和温室气体的影响.
无源日间辐射冷却器 (PDRC) 通过反射阳光和在没有电的情况下发出热量提供了一个替代方案,但通常需要厚厚的,昂贵的聚合物薄膜.
厚厚的PDRC薄膜增加了材料成本,并阻碍了高效的热传输,限制了它们的广泛采用.

研究的目的:

开发一种经济且可扩展的方法,用于制备薄型,高性能的被动日间辐射冷却器 (PDRC).
研究结晶性变化和孔隙形成对PDRC光学和热性质的影响.
为了证明开发的PDRC材料的实际冷却性能和潜在的节能.

主要方法:

基于溶剂蒸发的方法被用来制造层次的微型和纳米结构的聚乙烯化物-三乙烯薄膜.
诱导了结晶性改变以控制膜内的纳米孔的形成.
关键步骤包括在没有样本回火的情况下去除水残留物,以提高太阳光谱散射效率.

主要成果:

通过一种经济且可扩展的方法,成功制备了一个相对较薄的PDRC薄膜 (215μm).
优化后的PDRC显示出有效的户外冷却,实现了 Δ2.5 °C 的温度降低.
该材料的结构显著提高了整个太阳光谱的散射效率.

结论:

开发的薄型PDRC材料提供了一个可持续且具有成本效益的冷却解决方案.
预计在温暖的气候下,每年可能节省高达39%的能源,全国范围内节省715 GJ.
减少PDRC材料厚度对于实施可持续冷却和减轻碳足迹至关重要.

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