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Page 20 of 28 Wang et al. Soft Sci. 2026, 6, 8

Multi-functional integration of carbon-based aerogel
By utilizing the synergistic effects of heterogeneous components and porous network structures,
carbon-based microwave-absorbing aerogels demonstrate remarkable potential for integrating multiple
functionalities.

Specifically, due to the low thermal conductivity of air, aerogels with nano- and micro-scale pores can
effectively restrict heat conduction of gas molecules by forming a thermal insulation structure [141] .
Furthermore, oriented pore channels can not only suppress thermal convection but also promote the
propagation and dissipation of microwaves along the interconnected conductive networks, thereby enabling
both microwave absorption and thermal insulation simultaneously . For example, the anisotropic porous
[142]
structure of carbon-based aerogels with axial through-holes can be constructed via bidirectional freezing and
subsequent carbonization [143] . The interconnected conductive network with long-range ordered lamellar
layers and interlamellar bridges effectively promotes conduction loss along the parallel axis while impeding
heat flow in the vertical direction, achieving a high RL of -63.0 dB and broad EAB of 7.0 GHz with thermal
insulation properties. Additionally, incorporating non-conductive thermal insulating components such as
aramid nanofibers [144] or polyimide [145] to form an interpenetrating network with the conductive skeleton
enhances thermal management, thereby integrating infrared stealth performance into the
microwave-absorbing aerogel. Moreover, introducing MXene [146] components with both high electrical
conductivity and low infrared emissivity, combined with a multi-layered structure with gradient EM
response properties, results in an aerogel exhibiting an excellent RL of -60.1 dB at an ultrawide EAB of 14.1
GHz, along with compressibility. COMSOL Multiphysics® simulations were used to analyze the evolution of
power loss density in each layer, verifying the contribution of the gradient structures to the overall
performance.

Moreover, surface modifications can be regarded as effective strategies for multi-functionalization [147] . By
biomimicking the micro/nano roughness of lotus leaves, the hydrophobicity of carbon-based aerogels can be
enhanced through decoration with heterogeneous nanoparticles (Fe O /Fe/C , rare-earth oxide Nd O 3 [149] ),
[148]
3
4
2
which prevents water molecules from infiltrating the porous structure and affecting dielectric loss, thereby
endowing the aerogel with self-cleaning capabilities and stable microwave absorption performance under
humid conditions. Additionally, SiO and Al O can be used as corrosion-resistant coatings . For example,
[150]
2
3
2
Hou et al. prepared magnetic graphene-based aerogels through self-assembly, chemical reduction, and
freeze-drying, achieving a minimum RL of -51.3 dB and broad EAB of 6.64 GHz [151] . During chemical
reduction, the hydrophilic functional groups on the RGO surface were significantly reduced, resulting in
remarkable chemical inertness due to limited reactive groups, with enhanced corrosion resistance (low
corrosion potential of -0.45 V under a corrosion current density of 3.3 μA). This allowed the aerogel to
maintain stable microwave absorption performance after long-term immersion in NaCl solution,
demonstrating potential for critical marine applications. Zhang et al. doped highly electronegative fluorine
atoms onto graphene, synthesizing MXene/fluorinated graphene/cellulose nanofiber aerogels, which
significantly extended dipole relaxation times, achieving an ultrawide EAB of 9.08 GHz at a relatively low
thickness of 2.54 mm [152] . The hybrid aerogel exhibited multifunctionality: the parallel layered structure
decorated with MXene nanosheets enhanced the Joule heating effect and compressive strength, while the
aligned porous structure enabled infrared thermal camouflage.

Based on their high specific surface area and 3D interconnected pore structures, the multi-functionalization
of carbon-based aerogels can be achieved either by incorporating functional nanofillers or by tailoring
hetero-interfacial properties of the nanocomposites. This approach integrates microwave absorption with
thermal management, mechanical reinforcement, flame retardancy, and environmental stability, enabling
long-term practical applications under extreme conditions.