Creating an Eco-Friendly Building Coating with Smart Subambient Radiative Cooling

Xiao Xue, Meng Qiu, Yanwen Li, Q. M. Zhang, Siqi Li, Zhuo Yang, Chi Feng, Weidong Zhang, Jian Guo Dai, Dangyuan Lei, Wei Jin, Lijin Xu, Tao Zhang, Jie Qin, Huiqun Wang, Shanhui Fan

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

Subambient daytime radiative cooling (SDRC) provides a promising electricity- and cryogen-free pathway for global energy-efficiency. However, current SDRC systems require stringent surface designs, which are neither cost-effective nor eco-friendly, to selectively emit thermal radiation to outer space and simultaneously maximize solar reflectance. Here, a generic method is developed to upgrade the conventional building-coating materials with a peculiar self-adaptive SDRC effect through combining particle scattering, sunlight-excited fluorescence, and mid-infrared broadband radiation. It is also theoretically proved that heat exchange with the sky can eliminate the use of resonant microstructures and noble metal mirrors in conventional SDRC, and also leads to enhanced daytime cooling yet suppressed nighttime overcooling. When exposed to direct sunlight, the upgraded coating over an aluminum plate can achieve 6 °C (7 °C on a scale-model building) below the ambient temperature under a solar intensity of 744 W m−2 (850 W m−2), yielding a cooling power of 84.2 W m−2. The results pave the way for practical large-scale applications of high-performance SDRC for human thermal comfort in buildings.

Original languageEnglish
Article number1906751
JournalAdvanced Materials
Volume32
Issue number42
DOIs
Publication statusPublished - 1 Oct 2020

Keywords

  • broadband infrared emissivity
  • building coatings
  • fluorescent emissions
  • particle scatterings
  • smart subambient radiative cooling

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

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