In-Situ Growth and Graphitization Synthesis of Porous Fe₃O₄/Carbon Fiber Composites Derived from Biomass as Lightweight Microwave Absorber

Abstract

Biomass waste has emerged as a novel sustainable and renewable material for fabricating functional materials because of the lightweight and easy manufacturing. Herein, we synthesize a porous Fe 3 O 4 /carbon fiber (Fe 3 O 4 /CF) composites derived from bagasse waste by in-situ growth and a graphitization process. The Fe 3 O 4 nanocrystals uniformly embedded in porous CF significantly construct the multiple interfaces and hierarchical microstructure of Fe 3 O 4 /CF composites. Fe 3 O 4 /CF composites exhibit a maximum reflection loss value of −48.2 dB at 15.6 GHz with a thin thickness of only 1.9 mm. Meanwhile, a broad effective absorption bandwidth of 5.1 GHz covering the frequency range of 12.9−18.0 GHz is achieved. The rough surface, porous structure, and proper component contribute to the improved impedance matching. Meanwhile, the Debye relaxation and interfacial polarization dominantly promote the attenuation ability of the microwave. The enhancement of attenuation ability and impedance matching together account for the superior microwave absorption performance.

Facile synthesis of tubular magnetic carbon nanofibers by hypercrosslinked polymer design for microwave adsorption

“…The high‐resolution C1s spectra and deconvoluted curves of TMCF prepared at different temperature were present in Figure . The peaks centered at 285.2 and 284.4 eV, respectively, corresponded to C‐C bond and C=C bond 24 . Obviously, the content of C‐C bond decreased with carbonization temperature, but the C=C bond content increased gradually.…”

“…The peaks centered at 285.2 and 284.4 eV, respectively, corresponded to C-C bond and C=C bond. 24 Obviously, the content of C-C bond decreased with carbonization temperature, but the C=C bond content increased gradually. These results implied that with the increase in carbonization temperature, the carbon component in TMCF transformed from amorphous to graphite, and the carbonization degree was deepened.…”

Enhanced Microwave Absorption and Electromagnetic Properties of Si-Modified rGO@Fe3O4/PVDF-co-HFP Composites

“…The reason is that the negative µ" is attributed to the radiation of the magnetic energy [43]. According to the Maxwell equations [44], the charges transferred in variable electric field is easy to produce the induced magnetic field, which may result in the formation of the magnetic energy [45].…”

Enhanced electromagnetic wave absorption property of binary ZnO/NiCo2O4 composites

“…In recent years, due to the rapid applications of electronic devices, electromagnetic wave pollution, considered as the fourth pollution source, has aroused widely attentions in the scientific community [1][2][3][4][5][6]. This is because electromagnetic wave not only threats information security but also the health of human beings [7][8][9]. In the past few years, numerous effects have been conducted to weaken or eliminate this pollution [10][11][12][13][14][15].…”