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Page 22 of 34 Yan et al. Soft Sci. 2025, 5, 8 https://dx.doi.org/10.20517/ss.2024.66

Figure 8. Construction of lightweight EMI PCCs based on carbon material realization. (A) Preparation of PCNF films, multifunctional
integration schematic, thermal storage capacity, and EMI shielding mechanism. Reproduced with permission from ref [142] . Copyright
2022, American Chemical Society; (B) Preparation of SPP composites, digital images of mechanical properties, thermal conductivity,
chip thermal management performance, and EMI shielding schematics. Reproduced with permission from ref [143] . Copyright 2023,
Elsevier; (C) Preparation of PP/CNTs/Fe O /PW composites, material flexibility display schematic, thermal storage capacity and
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thermal conductivity, cell phone thermal management performance display, and EMI shielding mechanism. Reproduced with
permission from ref [144] . Copyright 2022, Elsevier. EMI: Electromagnetic interference; PCCs: phase change composites; PCNF: phase-
change nonwoven fabric; SPP: SWCNT/PEG/PDMS; PP: polypropylene; CNTs: carbon nanotubes; PW: paraffin wax.
graphene-based framework in addition to absorbing and holding significant amounts of PW, thereby
ensuring excellent shape stabilization of the prepared composite phase change material (CPCM).
Additionally, the synergistic effect of the high porosity and high electrical conductivity of the graphene-
based framework ensures that when incident EMWs enter the prepared CPCM, the high conductivity of the
graphene skeleton and numerous graphene interfaces cause repeated reflections within the micropores,
leading to significant attenuation of the EMWs. Meanwhile, the thermal conductivity path formed by the
porous graphene-based framework leads to a dramatic increase in thermal conductivity with the increasing
density of graphene. This, combined with the high energy storage density (189.10 J/g) provided by PW, was
used to evaluate the temperature-regulating capability of the thermal management components for
electronic cooling, and it was found that the temperature of the electronic products simulated to be almost
unchanged due to the latent heat of the phase change storage during the simulated operation, and the
maximum temperature is 8.9 °C lower than that of the electronic products without CPCM. This indicates
that it is a strong candidate for thermal management and efficient EMI shielding in electronic devices due to
its exceptional temperature control capability, quick thermal response, and great EMI shielding
performance. The combination of graphene and MXene to prepare thermal management materials with
EMI shielding performance may result in a synergistic effect, where the combined performance exceeds the
sum of their contributions. Hu et al. designed a dual-encapsulated multifunctional composite material by
constructing a graphene aerogel in a vertical MXene, and then thermal annealing treatment to construct a
highly hybridized semi-interpenetrating framework MXene-graphene foam (MGGF) with thermal/electrical
behavior [Figure 9B] . The framework composed of graphene and MXene demonstrates superior EMI
[146]
shielding performance due to its higher conductivity and more densely packed continuous network
compared to a single graphene framework. On the one hand, due to the large impedance mismatch
triggered by free electrons, the incident EMW interacts with the high density of electrons in the continuous
MGGF framework, which increases the conduction ohmic loss and leads to energy dissipation of
electromagnetic radiation. On the other hand, the hierarchical porous MGGF framework provides a large
number of interfaces and channels for multiple interlayer reflections of EMWs, increasing wave interactions
at multi-conducting interfaces and their propagation routes. This helps dissipate most of the residual
electromagnetic radiation and leads to additional attenuation through absorption, ultimately allowing only a
small fraction of EMWs to be transmitted. The dual-encapsulated composite also exhibits high thermal
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conductivity (11.39 W·m ·K ) and an optimal energy storage density (160.3 J/g), which is used to cool high-
power semiconductor devices. After 960 s of chip operation, the heatsink with MGGF not only reaches a
stable state more rapidly but also exhibits the lowest saturation temperature, allowing the chip to operate at
a lower temperature (6.8 °C) and extending its service life. This demonstrates the composite material’s
exceptional ability to reduce temperatures and achieve efficient thermal management. This dual-
encapsulation approach has far-reaching significance and guiding strategies for designing multifunctional
composites with excellent EMI shielding performance and ultra-efficient thermal management, and for
broadening their use in high-power electronics, artificial intelligence, and other fields.