Radiative cooling by tailoring surfaces with microstructures: Association of a grating and a multi-layer structure

Armande Hervé (1) , Jérémie Drevillon (1) , Younes Ezzahri (1) , Karl Joulain (1)

1 TNR - Thermique aux Nano échelles et Rayonnement [Institut Pprime]

We propose in this article a method to generate radiative coolers which are reflective in the solar spectrum and emissive in the transparency window of the atmosphere (8-13 µm). We choose an approach combining thermal control capacity of gratings and multi-layers. We use optimized BN, SiC and SiO 2 gratings, which have emissivity peak in the transparency window. We place under these gratings a metal/dielectric multi-layer structure to obtain a near perfect reflectivity in the solar spectrum and to enhance the emissivity in the transparency window. The optimized structures produce a good radiative cooling power density up to 80 W.m −2 .

Mots clés: Thermal emission; Solar energy; Subwavelength structures and nanostructures; Thermo-optical materials; Diffraction gratings; Multilayer design

Domaines: Thermique [physics.class-ph]; Optique [physics.optics]; Electromagnétisme; Micro et nanotechnologies/Microélectronique; Optique / photonique

Armande Hervé, Jérémie Drevillon, Younes Ezzahri, Karl Joulain. Radiative cooling by tailoring surfaces with microstructures: Association of a grating and a multi-layer structure. Journal of Quantitative Spectroscopy and Radiative Transfer, 2018, 221, pp.155-163. ⟨10.1016/j.jqsrt.2018.09.015⟩. ⟨hal-01680256⟩