Wentao Yu,Jiahui Lin,Yan Cao,Jiyong Fang,Ziqing Wang,Jintao Huang,Yonggang Min
This study successfully utilized a straightforward approach, choosing liquid–liquid phase separation to build a porous structure and synthesize composite absorbers based on polyimide-based porous carbon/Fe3C (PIC/Fe3C-1, PIC/Fe3C-2) nanoparticles and porous carbon/FeCo alloy nanoparticles (PIC/FeCo). The specially designed network structure pore structures contributed multiple reflection, conduction loss and strong interfacial polarization. After characterization, PIC/Fe3C-2 obtained minimum RL of −35.37 dB at 17.04 GHz with 1.55 mm thickness and effective absorption bandwidth of 4.95 GHz with 1.66 mm thickness. Furthermore, PIC/FeCo, with a thickness of 1.63 mm, exhibits the most robust electromagnetic wave loss ability at 15.6 GHz, with a minimum RL of −56.32 dB and an effective absorption bandwidth of 4.88 GHz. Thus, the design strategy presented in this study could serve as a model for synthesizing other high-performance absorbers, effectively mitigating electromagnetic wave-induced pollution.
Efficient electromagnetic wave absorption (EMA) materials are urgently needed to solve the increasingly serious electromagnetic pollution problems in both the modern military and civil fields. Multidimensional and multielement electromagnetic absorbing materials exhibit enormous potential in EMA applications owing to the combination of material and structure advantages. Herein, a three-dimensional (3D) reduced graphene oxide/Ti3C2Tx MXene/iron–cobalt alloy carbon (rGO/MXene/FeCoC) nanocomposite aerogel derived from FeCo-ZIF metal–organic frameworks (MOFs) was successfully fabricated by combining freeze-drying and pyrolysis methods. The minimum reflection loss (RLmin) of the optimized rGO/MXene/FeCoC-30% is −61.4 dB and the effective absorption band (EAB, <−10 dB) reaches up to 4.95 GHz with a matching thickness of 1.55 mm. The outstanding EMA performance benefits the excellent impedance matching, the rich multiple reflections and scattering in three-dimensional porous structures, and the favorable dielectric-magnetic synergistic losses endowed by graphene, MXene, and FeCoC nanoparticles. The successful construction of the multicomponent rGO/MXene/FeCoC nanocomposite aerogel provides a prospective direction for the development of high-efficient electromagnetic absorbing materials.
Tiantian Si,Shuai Xie,Zhijiang Ji,Zihao Wu,Chao Ma,Junyu Wu,Jing Wang
The development of practical and efficient electromagnetic wave (EMW) absorbing materials is a challenging research problem. A mussel-inspired molecular structure regulation strategy using polydopamine to increase the roughness and functional groups of basalt fiber (BF) surface, which can improve the fiber interfacial adhesion. Herein, a novel BF-Fe3O4/CNTs heterostructure is synthesized through a dip-coating adsorption process. The three-dimensional network structure of Fe3O4/CNTs hybrid in situ anchored on the surface of BF, which endows the composite to have good intrinsic magnetic and dielectric properties. Modulation of EMW absorption performance by controlling the addition of CNTs, the minimum RL of BF-Fe3O4/7C reaches to −40.57 dB at a thickness of 1.5 mm with CNTs addition of 7%. The enhanced EMW absorption performance of BF-Fe3O4/7C heterostructure may be attributed to the synergistic effects of interfacial polarization between the hollow magnetic Fe3O4 spheres and CNTs, conduction loss, magnetic resonance loss and multiple reflection/scattering inside the BF. This work provides a simple pathway to design EMW absorbing materials with good environmental stability.
危险品化学品经营许可证（带存储）