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arXiv · 2301.10338

Tuning Optical Properties of Metamaterials by Mie Scattering for Efficient Sub-ambient Daytime Radiative Cooling

Shiwen Wu·Ruda Jian·Lyu Zhou·Siyu Tian·Tengfei Luo·Shuang Cui·Bo Zhao·Guoping Xiong
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Abstract

The management of the abundant eggshell biowaste produced worldwide has become a problematic issue due to the generated odor and microorganisms after directly disposing eggshell biowaste in landfills. Herein, we propose a novel method to convert the hazardous eggshell biowaste to valuable resources for energy management applications. Eggshell-based films are fabricated by embedding eggshell powders into polymer matrix to achieve highly efficient sub-ambient daytime radiative cooling. Benefiting from the Mie scattering of eggshell particles/air pores in the solar spectrum and strong emission of eggshell in the mid-infrared (mid-IR) range, the eggshell-based films present high reflection of 0.96 in the solar spectrum and high emission of 0.95 in the mid-IR range, resulting in significant average temperature drop of 5{\deg}C and 12{\deg}C below the ambient temperature during daytime and nighttime, respectively. Moreover, the eggshell-based films exhibit excellent flexibility and self-cleaning properties, which are beneficial for practical long-term outdoor applications. Our proposed design provides a novel means for an environmentally friendly and sustainable management of the eggshell biowaste.

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Shiwen Wu, Ruda Jian, Lyu Zhou, Siyu Tian, Tengfei Luo, Shuang Cui, Bo Zhao, Guoping Xiong. 2023-01-24. Tuning Optical Properties of Metamaterials by Mie Scattering for Efficient Sub-ambient Daytime Radiative Cooling. https://arxiv.org/abs/2301.10338

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