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Hao et al. Soft Sci. 2025, 5, 39 https://dx.doi.org/10.20517/ss.2025.48 Page 5 of 25

[51]
electromagnetic waves . Molybdenum disulfide (MoS ) is a remarkable two-dimensional transition metal
2
disulfide compound that is gaining recognition as a significant material for microwave absorption due to its
dielectric loss absorption properties . The thin layer of MoS enables effective microwave penetration and
[52]
2
attenuation. Moreover, its plate-like structure minimizes eddy currents to the greatest extent, facilitating
resonance transfer to higher frequencies and broadening the absorption bandwidth . The floral layered
[53]
configuration of MoS is anticipated to exhibit superior microwave absorption performance as its surface
2
area increases and its structure becomes more intricate . Ceramic materials are another important type of
[54]
dielectric material. In recent years, high-entropy materials, particularly high-entropy ceramics, have
garnered increasing research attention within the scientific community . High-entropy oxides exhibit
[55]
pronounced stress concentration and lattice distortion due to mismatches in ionic quantities, sizes, and
bonding states . These structural characteristics generate defect configurations that are particularly
[56]
conducive to electromagnetic wave dissipation. For example, in spinel/perovskite high-entropy oxides,
around the interface of spinel and perovskite planes, notable stress concentrations and lattice distortions are
directly observed, inducing numerous point defects and stacking faults . The two biphasic high-entropy
[57]
oxides achieve optimized synergistic effects via precisely engineered phase composition control.

From the perspective of structural design, both dimensions and morphology play a pivotal role in tuning
microwave absorption characteristics. Currently, the functional units of MSMCs are predominantly
classified into microspheres and lamellar films. Microspheres exhibit outstanding advantages in terms of
flowability, close packing, dispersibility, and wear resistance. More importantly, the structural size can be
easily controlled, offering significant application potential in the preparation of MSMCs [58,59] . Zhao et al.
prepared graphene aerogel microspheres with outstanding elasticity and specific strength via a wet-spinning
[60]
technique [Figure 1A] . Notably, both horizontally and vertically grouped spheres manifested
superelasticity comparable to individual spheres, maintaining excellent shape recoverability even after 1,000
[60]
compression cycles at 70% strain . With the continuous exploration and application of microsphere-based
materials, various microsphere architectures have been developed, including core-shell microspheres,
hollow microspheres, and porous microspheres [61,62] . For instance, Tian et al. developed reduced graphene
aerogel microspheres with ring-like structure and regular layer spacing via wet spinning combined with
[63]
chemical reduction method . As shown in Figure 1B, the graphene microspheres displayed a unique chiral
helical structure and electromagnetic cross-polarization, as opposed to the disordered porous structure of
conventional aerogels. Such structural peculiarities are responsible for the improved impedance matching
and electromagnetic wave attenuation.

Apart from the influence of shape, the unit size affects the distribution of functional units in the matrix and
[64]
the content of fillers, which is very important for the regulation of microwave absorption performance .
Cai et al. designed polyimide-derived carbon/graphene hybrid aerogel microspheres via a process involving
high-pressure spraying, freeze-shaping, freeze-drying, in-situ thermal reduction, imidization, and high-
[65]
temperature thermal decomposition . The as-prepared microspheres exhibited a diameter of only ten
micrometers [Figure 1C]. Microspheres exhibited outstanding mechanical properties and could maintain a
complete structure in the matrix. Composite materials exhibited strong absorption amplitude and wide
absorption frequency range at low filler content and thin thickness, indicating that they are effective
candidate materials for ultra-light and high-efficiency electromagnetic wave absorbers . Dielectric ceramic
[65]
materials exhibit broad application prospects in the field of electromagnetic wave absorption, particularly
due to their unique corrosion resistance and high-temperature stability, which ensure reliable performance
[66]
under complex working conditions . Yang et al. synthesized composite TiAlCo ceramic microspheres
(composed of TiO , Co O , and Al O ) using spray drying technology . As illustrated in Figure 1D, the
[67]
4
2
3
2
3
microspheres measured approximately 50 μm, with each component maintaining a stable structure.