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A Janus emitter for passive heat release from enclosures
Se-Yeon Heo1, Gil Ju Lee1, Do Hyeon Kim1
1School of Electrical Engineering and Computer Science (EECS), Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea.
Science Advances
|September 12, 2020
Summary
Researchers developed a Janus emitter (JET) for passive radiative cooling. This technology cools surfaces and enclosed spaces by reflecting solar heat and emitting infrared radiation, mitigating the greenhouse effect.
Area of Science:
- Materials Science
- Nanotechnology
- Thermodynamics
Background:
- Passive radiative cooling reflects solar radiation and emits thermal infrared radiation for cooling.
- Cooling enclosed spaces, which trap heat via the greenhouse effect, remains a significant challenge.
- Existing radiative cooling technologies struggle with efficiency in enclosed environments.
Purpose of the Study:
- To present a novel Janus emitter (JET) capable of both surface and space cooling.
- To overcome the limitations of conventional radiative cooling in enclosed spaces.
- To demonstrate passive mitigation of the greenhouse effect using advanced materials.
Main Methods:
- Fabrication of a Janus emitter (JET) using an Ag-polydimethylsiloxane layer on a micropatterned quartz substrate.
- Utilizing induced spoof surface plasmon polaritons to enhance emissivity.
- Characterizing selective and broadband emission properties on separate sides of the emitter.
Main Results:
- The JET exhibits remarkable surface cooling performance, comparable to conventional radiative coolers.
- The JET effectively cools enclosed spaces when used as an enclosure wall, mitigating the greenhouse effect.
- The design overcomes inherent emissivity losses in polymers through plasmonic effects.
Conclusions:
- The Janus emitter (JET) offers a dual-functionality solution for passive cooling.
- This technology presents a viable method for passively reducing the greenhouse effect in enclosed environments.
- The JET demonstrates significant advancements in radiative cooling materials and applications.
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