Tunable smart mid infrared thermal control emitter based on phase change material VO2 thin film

• Published in: Applied thermal engineering Vol. 232; p. 121074
• Main Authors: Liang, Shiri, Xu, Feng, Li, Wenxin, Yang, Wenxing, Cheng, Shubo, Yang, Hua, Chen, Jing, Yi, Zao, Jiang, Peipei
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-09-2023
• Subjects: Mid-infrared; Phase change material; Temperature switchable; Thermal radiation; Thermal stability; Mid-infrared; Thermal radiation; Phase change material; Temperature switchable; Thermal stability
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2023.121074

Using phase change material VO2, we design intelligent thermal control emitter in mid-infrared band. The multilayer films composed of VO2-Ge-VO2-Ag have an emissivity of 0.78 at high temperature, an emissivity of 0.10 at low temperature, and a radiation regulation capacity of 0.68 at 5–13 μm. The structure has good thermal control emission performance. And it can be well used in aerospace, engineering insulation and other fields.
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•The thermal control emitter exhibits differential radiative capabilities due to its temperature switchable performance.•The thermal control emitter possesses tunability in peak wavelength.•The emitter demonstrates thermal stability both before and after the phase transition.•The performance of the emitter is essentially unaffected by variations in the incident angle and polarization angle.
Thermal radiation is one of the three ways of heat transfer, among which the mid-infrared thermal radiation has attracted much attention. At present, static control of thermal emissivity has been unable to meet the practical application, the device of dynamic control of thermal radiation is expected. In this paper, we study an intelligent thermal controlled radiation emitter based on a layered structure formed by phase change material Vanadium Dioxide. The transition denaturation of Vanadium Dioxide can realize the switching process from heat dissipation at high temperature to heat preservation at low temperature. In the mid-infrared wavelength range of 5–13 μm, significant differences in emission characteristics are observed due to variations in the imaginary part of the dielectric constant of Vanadium Dioxide. When it is in the high temperature metallic state, the optimal structural parameters, from top to bottom, are 10 nm, 350 nm, 320 nm, and 200 nm. With these parameters, the structure exhibits an emissivity of 0.78 and a full width at half maximum of 8.03 μm. This configuration achieves effective thermal radiation dissipation, as governed by the Stefan-Boltzmann’s law. On the other hand, when the structure is in the low temperature dielectric state, it exhibits a low absorption effect with an emissivity of 0.10, thus avoiding excessive heat loss. The radiative modulation capability and thermal stability were achieved through the use of thermochromic material Vanadium Dioxide which exhibits temperature switchable behavior. Additionally, the thermal control emitter, utilizing its resonant cavity, enables tunability of peak wavelength and demonstrates a certain degree of independence with respect to polarization and incident angle. The designed emitter structure is simple and easy to fabricate, holding significant prospects for applications in engineering insulation materials, infrared camouflage, and thermal management.