Tunable electromagnetic interference shielding ability of MXene/chitosan/silver nanowire sandwich films

2021 ◽  
pp. 2151041
Author(s):  
Wei Wang ◽  
Xiaoyu Bing ◽  
Yutong Zhou ◽  
Miaomiao Geng ◽  
Yanhu Zhan ◽  
...  

The structural design of thin films is attracting attention in academia and industry in attempts to improve electromagnetic interference shielding effectiveness (EMI SE). In this study, MXene/chitosan/silver nanowire (AgNW) sandwich films, in which the AgNW core layer was bordered by two MXene/chitosan layers, were fabricated by vacuum-assisted filtration. Because of the interconnected AgNWs in the core layer and the aligned MXene sheets in the MXene/chitosan layers, the electrical conductivity of the sandwich film reached 11,459.1 S/m. Consequently, the sandwich film exhibited an SE value of 82.3 dB. What is more, when both the AgNW and MXene contents were 33.3%, the sandwich film’s EMI SE divided by its thickness was 26,167 dB/cm, which was much superior to the values reported for inorganic hybrid composites and polymer composites filled with hybrid fillers. Such a simple approach was proved to be an effective way for further structure design of thin films in EMI shielding field.

2021 ◽  
pp. 095400832110645
Author(s):  
Karim Benzaoui ◽  
Achour Ales ◽  
Ahmed Mekki ◽  
Abdelhalim Zaoui ◽  
Boudjemaa Bouaouina ◽  
...  

The conventional electromagnetic interference (EMI) shielding materials are being gradually replaced by a new generation of supported conducting polymer composites (CPC) films due to their many advantages. This work presents a contribution on the effects of silane surface–modified flexible polypyrrole-silver nanocomposite films on the electromagnetic interference shielding effectiveness (EMI-SE). Thus, the UV-polymerization was used to in-situ deposit the PPy-Ag on the biaxial oriented polyethylene terephthalate (BOPET) flexible substrates whose surfaces were treated by 3-aminopropyltrimethoxysilane (APTMS). X-ray Photoelectron Spectroscopy (XPS) analyzes confirmed the APTMS grafting procedure. Structural, morphological, thermal, and electrical characteristics of the prepared films were correlated to the effect of substrate surface treatment. Thereafter, EMI-SE measurements of the elaborated films were carried out as per ASTM D4935 standard for a wide frequency band extending from 50 MHz to 18 GHz. The obtained results confirmed that the APTMS-treated BOPET film exhibit higher EMI shielding performance and better electrical characteristics compared to the untreated film. In fact, a 32% enhancement of EMI-SE was noted for the treated films compared to the untreated ones. Overall, these results put forward the role played by the surface treatment in strengthening the position of flexible PPy-Ag supported films as high-performance materials in electronic devices and electromagnetic interference shielding applications.


NANO ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. 2050143
Author(s):  
Bowen Feng ◽  
Wei Li ◽  
Fei Xue ◽  
Xingyu Tong ◽  
Jiaying Li ◽  
...  

In this work, graphene aerogels (GAs) with three-dimensional interconnected networks were prepared by chemical reduction and self-assembly of graphene oxide sheets. After microwave treatment, obtained microwave reduced graphene aerogels (MRGAs) were used in the preparation of bismaleimide (BMI) composites. The results show that the microwave treatment significantly enhanced the quality of GAs, and the three-dimensional networks in the GAs were well retained. Moreover, the MRGAs were highly efficient in endowing BMI with high electrical conductivity and excellent electromagnetic interference shielding effectiveness (EMI SE). The conductivity of MRGA/BMI composites was 42–68% higher than that of GA/BMI composites. When the filler content is 1.6 wt.%, the EMI SE of MRGA/BMI composite was 32.3% higher than that of GA/BMI composite in the X band.


Author(s):  
Hui Jia ◽  
Xiao Yang ◽  
Qing-Qiang Kong ◽  
Li-Jing Xie ◽  
Quan-Gui Guo ◽  
...  

A free-standing graphene oxide/Ag nanowire film with a dense sandwich-like structure was fabricated via vacuum-assisted self-assembly. The EMI SE is up to 62 dB when the thickness is merely 8 μm in 8–40 GHz. The corresponding specific SE (EMI SE/t) is up to 77 500 dB cm−1.


2019 ◽  
Vol 33 (10) ◽  
pp. 1950082 ◽  
Author(s):  
Wahyu Solafide ◽  
Ri-Ichi Murakami

The aim of this study is to discuss the effect of moisture absorption on electrical conductivity and electromagnetic interference of the carbon fiber (CF) reinforced bioplastic composite. The composites were prepared by the hot press machine, and immersed in water for 20 and 40 days. The electrical conductivity measurements were carried out as a function immersed time. The electrical conductivity of CF with two layers is greater than that of one layer, because the electrical conductivity increases with increasing the volume filler of CF. The electrical conductivity slightly increases with increasing the immersion time. The EMI SE (electromagnetic interference shielding effectiveness) of the composite was examined with the frequency from 500 MHz to 2000 MHz. The EMI SE of the CF increases with increasing the content of the CF, and the EMI SE result of composite is around 50 dB to 60 dB. There is scarcely significant effect of orientation on composite on the EMI SE.


Sign in / Sign up

Export Citation Format

Share Document