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Controllable Fabrication of SiC@C-Fe₃O₄ Hybrids and Their Excellent Electromagnetic Absorption Properties.

ABSTRACT: In this work, a batch of novel ternary hybrids (SiC@C-Fe₃O₄), characterized by SiC nanowires core, carbon shell, and adhered Fe₃O₄ nanoparticles were controllably synthesized via surface carbonization of SiC_nw followed by hydrothermal reaction. Carbon, which was derived from SiC with nanometer thickness, possesses an amorphous structure, while Fe₃O₄ nanoparticles are in a crystalline state. Simultaneously, the inducement of Fe₃O₄ nanoparticles can provide significant magnetic loss, which is well-tuned by changing the molar content of iron precursors (FeCl₃·6H₂O and FeCl₂·4H₂O). SiC@C-Fe₃O₄ hybrids show great electromagnetic absorption performance owing to the synergy effect of dielectric and magnetic losses. The minimum refection loss can reach to -63.71 dB at 11.20 GHz with a thickness of 3.10 mm, while the broad effective absorption bandwidth (EAB) can reach to 7.48 GHz in range of 10.52-18.00 GHz with a thickness of 2.63 mm. Moreover, the EAB can also cover the whole X band and Ku band. The outstanding performance of the obtained material implys that it is a promising candidate as an electromagnetic absorber.

SUBMITTER: Duan L

PROVIDER: S-EPMC8706827 | biostudies-literature |

REPOSITORIES: biostudies-literature

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