In:
Nanophotonics, Walter de Gruyter GmbH, Vol. 13, No. 5 ( 2024-03-12), p. 669-677
Abstract:
This study explores the optical design of a daytime radiative cooler with near-ideal solar reflectance and longwave infrared (LWIR) emittance through materials selection and nanostructuring. Focusing on polymers as a materials platform, we introduce a bilayer architecture, comprising a porous poly(vinylidene fluoride-co-hexafluoropropene) (P(VdF-HFP)) topcoat that serves as a low-index LWIR emissive effective medium, over a nanofibrous, solar scattering polytetrafluoroethene underlayer. This novel configuration yields a superwhite coating with a near-ideal solar reflectance of 〉 0.99, and a blackbody-like near-normal and hemispherical LWIR emittances of ∼0.98 and ∼0.96 respectively. Under humid and partially cloudy sky conditions unfavorable for radiative heat loss, these values enable the bilayer radiative cooler to achieve a sub-ambient of 2.3 °C. Given that the porous polymer bilayer uses scalable fabrication processes and commercially available materials, it holds significant promise for device-scale, as well as building thermoregulation applications.
Type of Medium:
Online Resource
ISSN:
2192-8614
DOI:
10.1515/nanoph-2023-0707
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2024
detail.hit.zdb_id:
2674162-3
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