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Passive Smart Thermal Control Coatings Incorporating CaF2/VO2 Core-Shell Microsphere Structures
Xueyu Wu1, Le Yuan2, Xiaolong Weng1
1National Engineering Research Center of Electromagnetic Radiation Control Materials, School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China.
Nano Letters
|April 29, 2021
Summary
Researchers developed a new smart thermal control coating using calcium fluoride/vanadium dioxide (CaF2@VO2) microspheres. This coating exhibits a reversible increase in emissivity with temperature, offering a power-free solution for thermal management.
Area of Science:
- Materials Science
- Nanotechnology
- Thermal Engineering
Background:
- Existing smart radiation devices have limitations like bulkiness and power demands.
- Need for advanced materials for efficient thermal management.
Purpose of the Study:
- To develop a smart thermal control coating overcoming limitations of current devices.
- To utilize the temperature-dependent properties of VO2 for tunable emissivity.
Main Methods:
- Fabrication of CaF2/VO2 core-shell microspheres using a solvent/hydrothermal-calcination method.
- Incorporation of microspheres into a polymer matrix for easy application.
- Investigation of optical and thermal properties through experimental analysis and simulations.
Main Results:
- Achieved a significant, reversible increase in emissivity from 0.47 at 30°C to 0.83 at 90°C.
- Demonstrated the tunable optical scattering and absorption properties of CaF2@VO2 microspheres.
- Validated the underlying mechanisms through theoretical analysis and numerical simulations.
Conclusions:
- The CaF2@VO2 core-shell microsphere coating offers a promising, power-free solution for smart thermal control.
- This technology can advance the development of novel coating materials for dynamic thermal management applications.
- The study provides a foundation for further research into advanced radiative cooling and heating materials.
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