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Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
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Highly tunable thermal emitter with vanadium dioxide metamaterials for radiative cooling
Applied Optics
|July 15, 2021
Summary
Vanadium dioxide metamaterials enable efficient selective radiative cooling. This novel tunable emitter achieves high emissivity and cooling power, benefiting dynamic cooling systems and intelligent windows.
Area of Science:
- Materials Science
- Nanotechnology
- Optics
Background:
- Radiative cooling offers a passive method for heat dissipation.
- Vanadium dioxide (VO2) exhibits a phase transition with tunable optical properties.
- Metamaterials provide a platform for manipulating electromagnetic waves.
Purpose of the Study:
- To develop an efficient thermal emitter for selective radiative cooling.
- To optimize VO2 metamaterials for enhanced emissivity within the atmospheric window.
- To investigate the performance of the emitter for practical cooling applications.
Main Methods:
- Fabrication of patterned VO2 metamaterials on a multilayer substrate.
- Integration of a top composite layer to enhance emissivity.
- Optimization of the composite layer and thermal stimuli.
- Investigation of angular and geometric parameter effects on emissivity.
- Calculation of cooling power.
Main Results:
- Achieved a maximum emissivity of 0.952 in the metallic phase of VO2 within the atmospheric window.
- Demonstrated strong electric field localization within the metamaterial cavity.
- Calculated a high cooling power of 710 W/m² at 383 K.
- Investigated the influence of incident angles and geometric parameters.
Conclusions:
- The proposed tunable emitter exhibits high performance for selective radiative cooling.
- The design is beneficial for dynamic radiative cooling systems.
- Potential applications include building cooling and intelligent windows.
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