Bioinspired radiative cooling coating with high emittance and robust self-cleaning for sustainably efficient heat dissipation

Abstract

To overcome the overheating phenomena of electronic devices and energy components, developing advanced energy-free cooling coatings with promising radiative property seem an effective and energy-saving way. However, the further application of these coatings is greatly limited by their sustainability because of their fragile and easy contamination. Herein, it is reported that a bioinspired radiative cooling coating (BRCC) displayed sustainably efficient heat dissipation by the combination of high emittance and robust self-cleaning property. With the hierarchical porous structure constructed by multiwalled carbon nanotubes (MWCNTs), modified SiO₂ and fluorosilicone (FSi) resin, the involvement of the BRCC improves the cooling performance by increasing ≈25% total heat transfer coefficient. During the abrasion and soiling tests, the BRCCcoated Al alloy heat sink always displays stable radiative cooling performance.Moreover, the simulation and experimental results both revealed that reducing surface coverage of BRCC (≈80.9%) can still keep highly cooling efficiency, leading to a cost-effective avenue. Therefore, this study may guide the design and fabrication of advanced radiative cooling coating.

Keywords

Al alloy heat sink / cooling efficiency / heat dissipation / self-cleaning / superhydrophobic

RIGHTS & PERMISSIONS

2023 The Authors. Exploration published by Henan University and John Wiley & Sons Australia, Ltd.