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Fan et al. Soft Sci 2024;4:43 https://dx.doi.org/10.20517/ss.2024.63 Page 3 of 10

Figure 1. Schematic of MAMs derived from MOF in different dimensions. Reprinted with permission [37-44] . MAMs: Microwave absorbing
materials; MOF: Metal-organic framework.

interfaces. Consequently, a RL of -52.66 dB is achieved, and the EAB achieves full coverage of the
min
Ku-band [Figure 2G].

One-dimensional MOF-derived materials are crucial in MAMs for their unique structure that facilitates
conductive network formation. Template strategies are often employed for their synthesis. Xue et al.
successfully prepared Co/MnO/carbon nanotube (CNT) composites by template method . ZIF-8@ZIF-67
[46]
was fabricated on MnO nanorods using the precipitation method. Then, after metal catalysis and
2
carbonation, a Co/MnO/CNT layered structure was formed [Figure 2H]. ZIF-8 is coated on the MnO 2
surface, forming a rough core-shell structure [Figure 2I]. Carbonization causes structural collapse,
eventually forming a layered structure resembling a caterpillar [Figure 2J]. The structure has good
impedance matching [Figure 2K]. Under the synergy of magnetic and dielectric loss, the composite material
achieves a strong MA of -58.0 dB and 4.5 GHz at an ultrathin matching thickness.

Two-dimensional MOF-derived MAMs are gaining attention for their high specific surface area and low
density, with the stripping method being a common preparation technique for 2D MOF derivatives. Yan et
al. first mixed Zn(NO ) with methylimidazole to produce Zn-ZIF-L. Subsequently, metal chloride was
3 2
added as a stripping agent and an etchant. The ZIF-L layer was exfoliated into N-doped porous graphene
[47]
carbon nanonets (N-GN) [Figure 2L] . Because of the evaporation of Zn, the nanosheets are porous
[Figure 2M and N]. The good structure, N heteroatoms, large pores, and abundant heterogeneous interfaces
all lay the foundation for excellent MA properties. The optimum RL of -54 dB is achieved with a
filler loading of 3 wt.%.