结构性多孔陶,用于有效的白天下环境辐射冷却
Jieyan Zhao1,2, Qing Meng1, Yong Li1
1Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
ACS applied materials & interfaces
|September 26, 2023
概括
一种新的多孔化-化陶提供被动建筑冷却. 这种材料达到显著的环境下温度和高机械强度,克服了以前基于纤维素的选项的局限性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 可持续能源 可持续能源
背景情况:
- 被动辐射冷却提供了无能源的建筑气候控制.
- 基于纤维素的复合材料看起来很有前途,但缺乏耐用性和耐火性.
- 需要先进的结构材料来实现高效可靠的辐射冷却.
研究的目的:
- 开发一种耐用,高性能的结构材料,用于被动辐射冷却.
- 解决现有的基于纤维素的辐射冷却材料的局限性.
- 研究化-化陶在建筑应用中的潜力.
主要方法:
- 一步燃烧合成多孔化-化 (Si3N4-BN) 陶.
- 光学属性的表征 (太阳反射率,大气窗口发射率).
- 评估机械强度 (柔性和压力) 和隔热.
主要成果:
- 实现了高太阳反射率 (~0.95) 和大气窗口辐射率 (~0.95).
- 在直接阳光下,其已证明的环境下辐射冷却性能为5.14°C.
- 具有出色的机械性能,屈曲强度为31.07MPa,压力强度为65.36MPa.
结论:
- 多孔Si3N4-BN陶是被动辐射冷却的一个有前途的材料.
- 该材料与基于纤维素的替代品相比,具有更高的耐用性和机械强度.
- 在热带沙漠和岛屿等苛刻环境中,它显示了建筑冷却的巨大潜力.
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