A smart thermal-gated bilayer membrane for temperature-adaptive radiative cooling and solar heating

Xinzhe Min; Xueyang Wang; Jinlei Li; Ning Xu; Xiran Du; Mengyue Zeng; Wei Li; Bin Zhu; Jia Zhu

doi:10.1016/j.scib.2023.08.003

A smart thermal-gated bilayer membrane for temperature-adaptive radiative cooling and solar heating

Sci Bull (Beijing). 2023 Sep 30;68(18):2054-2062. doi: 10.1016/j.scib.2023.08.003. Epub 2023 Aug 4.

Authors

Xinzhe Min¹, Xueyang Wang¹, Jinlei Li¹, Ning Xu¹, Xiran Du¹, Mengyue Zeng¹, Wei Li², Bin Zhu³, Jia Zhu⁴

Affiliations

¹ National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
² GPL Photonics Laboratory, State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. Electronic address: weili1@ciomp.ac.cn.
³ National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China. Electronic address: binzhu@nju.edu.cn.
⁴ National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China. Electronic address: jiazhu@nju.edu.cn.

PMID: 37599177
DOI: 10.1016/j.scib.2023.08.003

Abstract

Due to the huge energy consumption of traditional cooling- and heating-based electricity, passive radiative cooling and solar heating with a minimum carbon footprint using the outer space and Sun as natural thermodynamic resources have attracted much attention. However, most passive devices are static and monofunctional, and cannot meet the practical requirements of dynamic cooling and heating under various conditions. Here, we demonstrate a smart thermal-gated (STG) bilayer membrane that enables fully automatic and temperature-adaptive radiative cooling and solar heating. Specifically, this device can switch from reflective to absorptive (white to black) in the solar wavelength with the reduction in optical scattering upon ambient temperature, corresponding to a sunlight reflectivity change from 0.962 to 0.059 when the temperature drops below ∼30 °C, whereas its mid-infrared emissivity remains at ∼0.95. Consequently, this STG membrane achieves a temperature of ∼5 °C below ambient (a key signature of radiative cooling) under direct sunlight (peak solar irradiance >900 W m^-2) in summer and a solar heating power of ∼550 W m^-2 in winter. Theoretical analysis reveals the substantial advantage of this switchable cooling/heating device in potential energy saving compared with cooling-only and heating-only strategies when widely used in different climates. It is expected that this work will pave a new pathway for designing temperature-adaptive devices with zero energy consumption and provide an innovative way to achieve sustainable energy.

Keywords: Al(2)O(3) nanoparticles; Radiative cooling; Solar heating; Switchable Al(2)O(3) NPs-composited PNIPAm hydrogel; Temperature control.