Lightweight, robust, and thin aerogel films with multifunctionality
are highly desirable to meet the technological demands of current
society. However, fabrication and application of these multifunctional
aerogel films are still significantly underdeveloped. Herein, we demonstrate
a multifunctional aerogel film composed of strong aramid nanofibers
(ANFs), conductive carbon nanotubes (CNTs), and hydrophobic fluorocarbon
(FC) resin. The obtained hybrid aerogel film exhibits large specific
surface area (232.8 m2·g–1), high
electrical conductivity (230 S·m–1), and excellent
hydrophobicity (contact angle of up to 137.0°) with exceptional
Joule heating performance and supreme electromagnetic interference
(EMI) shielding efficiency. The FC coating renders the hydrophilic
ANF/CNT aerogel films hydrophobic, resulting in an excellent self-cleaning
performance. The high electrical conductivity enables a low-voltage-driven
Joule heating property and an EMI shielding effectiveness (SE) of
54.4 dB in the X-band at a thickness of 568 μm. The specific
EMI SE is up to 33528.3 dB·cm2·g–1, which is among the highest values of typical metal-, conducting-polymer-,
or carbon-based composites. This multifunctional aerogel film holds
great promise for smart garments, electromagnetic wave shielding,
and personal thermal management systems.