可扩展的超冷水泥
Guo Lu1, Fengyin Du1,2, Zhen Wang1
1State Key Laboratory of Engineering Materials for Major Infrastructure, School of Materials Science and Engineering, Southeast University, Nanjing 211189, China.
Science advances
|August 20, 2025
概括
研究人员开发了一种新的冷却水泥, 这种耐用,高性能材料可显著降低温度,并带来潜在的负碳足迹.
科学领域:
- 材料科学
- 土木工程
- 可持续技术
背景情况:
- 无源日间辐射冷却 (PDRC) 材料提供可持续的建筑冷却解决方案.
- 在开发耐用,可扩展的PDRC结构材料方面存在挑战.
研究的目的:
- 用于实际的土木工程应用, 合成一个超表面增强的冷却水泥.
- 解决当前PDRC材料在耐用性,部署和可扩展性方面的局限性.
主要方法:
- 在低碳水泥生产过程中采用了通用,可扩展的压力驱动制造策略.
- 通过反射性膜和层次性毛孔的自组装来实现元表面增强.
- 材料的特性包括太阳反射率,中红外辐射率,强度和对恶劣条件的抗性.
主要成果:
- 采用光子架构的水泥实现了高太阳反射率 (96.2%) 和中红外辐射率 (96.0%).
- 在中午条件下 (850 W/m2太阳强度) 记录了5.4°C的温度下降.
- 这种水泥在各种恶劣的暴露下表现出其固有的高强度,耐磨性和光学稳定性.
结论:
- 开发的冷却水泥是可持续建筑冷却的有希望,耐用和可扩展的解决方案.
- 这种材料具有出色的性能和弹性,适用于苛刻的土木工程应用.
- 一个以机器学习为指导的生命周期评估表明这种创新材料的潜在净负碳排放情况.
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