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

Nanomaterials ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3438
Author(s):  
Liqun Duan ◽  
Xiaoqing Dai ◽  
Fan Wu ◽  
Aming Xie ◽  
Jian-An Wu ◽  
...  

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 SiCnw 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.

2016 ◽  
Vol 4 (38) ◽  
pp. 8897-8902 ◽  
Author(s):  
Mengxiao Sun ◽  
Xuliang Lv ◽  
Aming Xie ◽  
Wanchun Jiang ◽  
Fan Wu

Nowadays, only by balancing the relationship of electromagnetic applications and electromagnetic pollution management can human health and quality of life be guaranteed.


2016 ◽  
Vol 31 (6) ◽  
pp. 567 ◽  
Author(s):  
XU Shuang-Shuang ◽  
CHEN Gong ◽  
ZHANG Hai-Qin ◽  
CHEN Yuan ◽  
ZHAO Yan

2021 ◽  
Vol 31 (4) ◽  
pp. 249-255
Author(s):  
Zuoqun Zhang ◽  
Chaoshan Yang ◽  
Hua Cheng ◽  
Xiaohan Huang ◽  
Yuhao Zhu

Now there’re many researches on the electromagnetic radiation protection function of the cement-based electromagnetic wave absorbing materials, such materials have been widely used in various types of buildings. This paper proposed an idea for preparing a cement-based composite material by mixing functional aggregates with high content of Fe2O3 and SiC, that is, adding Fe3O4 powder and nano-SiC of different contents in the clay, and then sintering at 1190℃; the prepared aggregates showed obvious magnetic loss and dielectric loss to electromagnetic waves, and the numerical tube pressure could reach 16.83MPa. The double-layer reflectivity test board made of functional aggregates showed excellent electromagnetic wave absorption performance, its reflection loss was less than -10dB in the frequency range of 8~18GHz (corresponding to energy absorption greater than 90% EM), and its maximum RL reached -12.13dB. In addition, the compressive strength of the cement-based composite material at the age of 28 days reached 50.1 MPa, which can meet the strength requirements of building materials.


2019 ◽  
Vol 32 (2) ◽  
pp. 385-390
Author(s):  
H.K. AbdulKadir

The conductive polymers such as polyaniline (PANI) exhibit considerable electrical conductive properties. The coating of PANI with magnetic (Fe3O4) nanoparticles formed composites (PANI/Fe3O4) with required dielectric properties. The morphology result study of PANI/Fe3O4 by field emission scanning electron microscope (FESEM) indicate the presence of PANI with tubes like structure containing different wt % of Fe3O4 nanoparticles (5, 15, 25 wt %). The structural pattern investigated by XRD revealed the presence of Fe3O4 nanoparticles at 2θ = 35.58º, while the amorphous structure indicates the presence of PANI matrix. However, the chemical bonding analysis using FTIR shows chemical conjugation of bonds at 3336, 3300 and 3277 cm-1 due to presence of NH group in PANI and OH group in Fe3O4 nanoparticles, while presence of 504 and 526 cm-1 suggesting that Fe3O4 nanoparticles are present in the composites materials. The dielectric properties study by 4-point probe and VSM shows that PANI and PANI/Fe3O4 nanocomposites exhibit good electrical properties (1.55 to 1.35 S/cm) which are decreasing with increase of Fe3O4 nanoparticles, may be resulting due to insulating behaviour of the magnetic nanoparticles, while the magnetic properties of PANI/Fe3O4 nanocomposites indicate super paramagnetic properties with saturation magnetization of (59.4, 5.96, 11.94 and 15.43 emus/g).


2020 ◽  
Vol 262 ◽  
pp. 116349
Author(s):  
Zhaohui Qin ◽  
Chunyu Wang ◽  
Peng Zhang ◽  
Xingji Li ◽  
Hong Xu ◽  
...  

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