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arXiv · 2207.10957

Scalable colored sub-ambient radiative coolers based on a polymer-Tamm photonic structure

Tianzhe Huang·Qixiang Chen·Jinhua Huang·Yuehui Lu·Hua Xu·Meng Zhao·Yao Xu·Weijie Song
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Abstract

Daytime radiative coolers cool objects below the air temperature without any electricity input, while most of them are limited by a silvery or whitish appearance. Colored daytime radiative coolers (CDRCs) with diverse colors, scalable manufacture, and sub-ambient cooling have not been achieved. We introduce a polymer-Tamm photonic structure to enable a high infrared emittance and an engineered absorbed solar irradiance, governed by the quality factor (Q-factor). We theoretically determine the theoretical thresholds for sub-ambient cooling through yellow, magenta, and cyan CDRCs. We experimentally fabricate and observe a temperature drop of 2.6-8.8 degrees Celsius on average during daytime and 4.0-4.4degrees Celsius during nighttime. Furthermore, we demonstrate a scalable-manufactured magenta CDRC with a width of 60 cm and a length of 500 cm by a roll-to-roll deposition technique. This work provides guidelines for large-scale CDRCs and offers unprecedented opportunities for potential applications with energy-saving, aesthetic, and visual comfort demands.

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Tianzhe Huang, Qixiang Chen, Jinhua Huang, Yuehui Lu, Hua Xu, Meng Zhao, Yao Xu, Weijie Song. 2022-07-22. Scalable colored sub-ambient radiative coolers based on a polymer-Tamm photonic structure. https://doi.org/10.1021/acsami.2c23270

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