Recent Advances in Structural Design of Carbon/Magnetic Composites and their Electromagnetic Wave Absorption Applications

Electromagnetic pollution protection and military stealth technologies underscore the urgent need to develop efficient electromagnetic wave-absorbing materials (EWAMs). Traditional EWAMs suffer from single absorption loss mechanisms, poor impedance matching, and weak reflection loss. To date, combining dielectric loss with magnetic loss in EWAMs have proven to be an effective approach to enhancing electromagnetic absorption performance. The structural design of composites plays a pivotal role in improving impedance matching and enhancing the attenuation of electromagnetic waves. It is widely regarded as one of the principal methods for fine-tuning electromagnetic parameters and response mechanisms. Among these, composites of carbon and magnetic materials have become a research hotspot due to their magnetoelectric synergistic effects and versatile microstructure design. Herein, the principles of electromagnetic wave absorption in terms of both the loss mechanism and impedance matching are outlined. The research progress on core-shell, skeleton, and hollow structure of carbon/magnetic composite EWAMs are summarized. The synthesis methods, absorption properties, and attenuation mechanisms of composites with these structures are described in detail. Finally, the limitations of carbon/magnetic composites in electromagnetic wave absorption are discussed, possible solutions are proposed, and future development directions for carbon/magnetic composite EWAMs are envisioned.