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Page 14 of 28 Wang et al. Soft Sci. 2026, 6, 8

Figure 5. The construction and microwave absorption properties of (A) Ni/MXene/RGO aerogel [116] and (B) WCC foams [117] with different
pore orientations. Reproduced with permission [116] . Copyright 2021, American Chemical Society. Reproduced with permission [117] . Copyright
2025, Springer Nature. WCC: Tungsten carbide carbon foam; GO: graphene oxide; RL: reflection loss; EAB: effective absorption bandwidth.

parameters from the surface to the interior, thereby enabling efficient dissipation of incident microwaves
across a broad frequency range at distinct depths.

Specifically, the outermost layer of the aerogel typically exhibits a highly macroporous microstructure with
an effective impedance closely matched to that of free space, which minimizes surface reflection and
facilitates deeper penetration of incident microwaves into the aerogel. As the pore structure and conductive
network density progressively vary across successive layers, the gradual increase in effective permittivity and
permeability within the intermediate region promotes propagation and dissipation of incident microwaves
via dielectric and magnetic loss. Subsequently, the microwaves reflect from the bottom of the aerogel to the
middle layer, where they interfere with incoming waves of opposite phase, thereby consuming microwave
energy through repeated interactions with the carbon-based framework. By constructing an
“absorption-reflection-reabsorption” transmission path, the microwaves are dissipated and converted to
thermal energy over an exceptionally wide frequency range, resulting in a significant enhancement of EAB
compared to conventional homogeneous aerogels. In addition, computer simulation technology (CST)
simulations of the electric field, magnetic field, and power loss distribution were conducted to highlight the
role of the gradient structure in optimizing impedance matching and enhancing the multi-reflection effect
within the aerogel [118-121] .

The orientation and alignment of the porous structure also play a critical role in tailoring microwave
response . Conventional isotropic freeze-drying or chemical foaming methods typically produce aerogels
[122]
with disordered, randomly oriented pores, which lead to limited control over microwave propagation
pathways and only modest improvement in attenuation. In contrast, aerogels with vertically aligned,
anisotropic pore channels offer advantages through directional templating strategies. Specifically, the aligned
channels allow microwaves to penetrate the aerogel along the pore axis with minimal interfacial reflection.
Moreover, the aligned pore walls promote directional reflection and scattering of microwaves within the
aerogel, facilitating repeated interactions with the conductive carbon framework and thereby enhancing
energy dissipation over an ultrabroad frequency range.

Other soft-templates
In addition to obtaining 3D porous structures through freeze-drying technology using ice templates,
templates such as silicon dioxide (SiO ) microspheres, polystyrene (PS) microspheres, polymethyl
2