Bioinspired radiative cooling coating with high emittance and robust
self-cleaning for sustainably efficient heat dissipation
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, we report that a bioinspired radiative cooling coating (BRCC)
displayed sustainably efficient heat dissipation by the combination of
high emittance and robust self-cleaning property. With hierarchical
porous structure constructed by multiwalled carbon nanotubes (MWCNTs),
modified SiO2 and FSi resin, the involvement of the BRCC improves the
cooling performance by increasing ca. 25% total heat transfer
coefficient. During the abrasion and soiling tests, the robust
self-cleaning capability endows BRCC-coated Al alloy heat sink with
stable radiative cooling performance. Moreover, the simulation and
experimental results both revealed that reducing surface coverage of
BRCC (ca. 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.