Realizing ultra-wideband absorption, desirable attenuation capability at high temperature and mechanical requirements for real-life applications remains a great challenge for microwave absorbing materials. Herein, we have constructed a porous carbon fiber/polymethacrylimide (CP) structure for acquiring promising microwave absorption performance and withstanding both elevated temperature and high strength in a low density. Given the ability of porous structure to induce desirable impedance matching and multiple reflection, the absorption bandwidth of CP composite can reach ultra-wideband absorption of 14 GHz at room temperature and even cover the whole X-band at 473 K. Additionally, the presence of imide ring group in polymethacrylimide and hard bubble wall endows the composite with excellent heat and compressive behaviors. Besides, the lightweight of the CP composite with a density of only 110 mg cm⁻³ coupled with high compressive strength of 1.05 MPa even at 453 K also satisfies the requirements in engineering applications. Compared with soft and compressible aerogel materials, we envision that the rigid porous foam absorbing material is particularly suitable for environmental extremes.

High-entropy doping (HED) engineering surpasses conventional methods for optimizing atomic configurations and electronic structures, opening new paths for developing advanced electromagnetic wave absorbing (EWA) materials. However, the application of anionic HED engineering to tailor EWA mechanisms remains unexplored. Herein, we employ in situ pyrolysis combined with a three-stage solvent thermal doping procedure to systematically induce anion multibody interactions, thereby facilitating the inheritance and accumulation of beneficial EWA properties. The research shows that anions with various electronegativities precisely balance free charges and create a significant localized charge imbalance, triggering the ‘directional cocktail effect’. This effect induces an optimal dielectric loss mechanism and enhances the EWA performance. With only 7.5 wt% filling, the effective absorption bandwidth and minimum reflection loss are 7.05 GHz and −60 dB, respectively. Overall, we report an anionic HED engineering within thin a graphite framework, which may be conceptually extendable for electromagnetic modulation of other two-dimensional van der Waals EWA materials.

3D conductive networks constructed by decorating petal-like Ni-based MOFs on the surface of graphene nanosheets exhibit superior microwave absorption properties.

With the development of nanotechnology, nano-functional units of different dimensions, morphologies, and sizes exhibit the potential for efficient microwave absorption (MA) performance. However, the multi-unit coupling enhancement mechanism triggered by the alignment and orientation of nano-functional units has been neglected, hindering the further development of microwave absorbing materials (MAMs). In this paper, two typical ZIF-derived nanomaterials are self-assembled into two-dimensional ordered polyhedral superstructures by the simple ice template method. The nano-functional units exhibit distinctive dielectric-sensitive behaviors after self-assembling into two-dimensional ordered arrays. The modified 2D ordered polyhedral superstructures not only inherit the atomic-level doping and well-designed shell structure, but also further amplify the loss properties to realize the multi-scale modulated MA response. Satisfactory MA performance in C, X and Ku bands is finally achieved. In particular, the ultra-broadband microwave absorption bandwidth (EAB) of 6.41 GHz is realized at 1.82 mm thickness. Our work demonstrates the two-dimensional ordered array-induced multiscale polarization behavior, providing a direction to fully utilize the potential of wave-absorbing functional units.