Phase-change materials reinforced intelligent paint for efficient daytime radiative cooling
Mulin Qin1, Feng Xiong1, Waseem Aftab1
1Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, School of Materials Science and Engineering, Peking University, Beijing 100871, P. R. China.
Iscience
|July 5, 2022
Summary
This study introduces a new radiative paint that stores heat using phase-change materials (PCMs). This innovation enhances passive cooling performance for buildings, contributing to energy savings.
Area of Science:
- Materials Science
- Sustainable Energy
- Building Physics
Background:
- Passive cooling is crucial for green building development.
- Daytime radiative cooling technology (DRCT) shows promise but is limited by heat absorption.
- Existing DRCT faces challenges with heat gain from sunlight and surroundings, reducing cooling efficiency.
Purpose of the Study:
- To develop an enhanced passive cooling solution for buildings.
- To improve the performance of daytime radiative cooling technology (DRCT).
- To create a bifunctional radiative paint with latent heat storage capacity.
Main Methods:
- Developed a novel radiative paint by integrating phase-change material (PCM) microcapsules within an acrylic resin matrix.
- Engineered the paint for high reflectivity in the solar spectrum and strong emissivity in the atmospheric window.
- Investigated the paint's thermal properties, including phase transition temperature and enthalpy.
- Conducted temperature measurements to evaluate cooling performance and time-buffering effects.
Main Results:
- The bifunctional paint demonstrated effective latent heat storage through its integrated PCMs.
- The paint exhibited high reflectivity and emissivity, crucial for radiative cooling.
- Temperature measurements confirmed enhanced cooling performance, including a greater temperature drop and a time-buffering effect compared to pure radiative paint.
- The material showed a suitable phase transition temperature and high enthalpy for effective heat management.
Conclusions:
- The developed radiative paint with latent heat storage significantly enhances passive cooling efficiency.
- This technology offers a promising approach to overcome limitations of traditional DRCT.
- The findings suggest broad potential for integrating PCMs and DRCT in buildings for energy conservation and environmental protection.
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