A facile method to improving the electromagnetic interference shielding of a free-standing and foldable carbon nanotube mat

RSC Advances ◽  
2016 ◽  
Vol 6 (67) ◽  
pp. 62485-62490 ◽  
Author(s):  
Zi Ping Wu ◽  
Ting Liu ◽  
De Ming Chen ◽  
Gao Wu ◽  
Qing Hui Wang ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Saturation Magnetization ◽  
Electromagnetic Interference ◽  
Electrical Resistance ◽  
High Saturation Magnetization ◽  
Electromagnetic Interference Shielding ◽  
Free Standing ◽  
High Saturation ◽  
Mat Thickness ◽  
Emi Se

Free-standing and foldable CNT mats with high saturation magnetization and low electrical resistance were prepared, and a high EMI SE of 40.4–60.3 dB can be achieved at frequency ranges of 1 GHz to 18 GHz with a low mat thickness of 1.0 μm.

Electrically conductive and electromagnetic interference shielding of polyethylene composites with devisable carbon nanotube networks

2015 ◽  
Vol 3 (36) ◽  
pp. 9369-9378 ◽  
Author(s):  
Li-Chuan Jia ◽  
Ding-Xiang Yan ◽  
Cheng-Hua Cui ◽  
Xin Jiang ◽  
Xu Ji ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Electromagnetic Interference ◽  
Electromagnetic Interference Shielding ◽  
Electrically Conductive ◽  
Carbon Nanotube Networks ◽  
Emi Se ◽  
Segregated Structure ◽  
Polyethylene Composites

A segregated structure results in an EMI SE up to 46.4 dB in CNT/polyethylene composites with only 5 wt% CNTs.

Free-standing, anti-corrosion, super flexible graphene oxide/silver nanowire thin films for ultra-wideband electromagnetic interference shielding

2021 ◽  
Author(s):  
Hui Jia ◽  
Xiao Yang ◽  
Qing-Qiang Kong ◽  
Li-Jing Xie ◽  
Quan-Gui Guo ◽  
...  
Keyword(s):  
Thin Films ◽  
Graphene Oxide ◽  
Self Assembly ◽  
Electromagnetic Interference ◽  
Silver Nanowire ◽  
Ultra Wideband ◽  
Electromagnetic Interference Shielding ◽  
Free Standing ◽  
Emi Se ◽  
Ag Nanowire

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.

A strong and tough polymer–carbon nanotube film for flexible and efficient electromagnetic interference shielding

2017 ◽  
Vol 5 (35) ◽  
pp. 8944-8951 ◽  
Author(s):  
Li-Chuan Jia ◽  
Meng-Zhu Li ◽  
Ding-Xiang Yan ◽  
Cheng-Hua Cui ◽  
Hong-Yuan Wu ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Electromagnetic Interference ◽  
Electromagnetic Interference Shielding ◽  
Carbon Nanotube Film ◽  
Emi Se

A strong and tough CNT-NR film with excellent EMI SE (44.7 dB@250 μm) is realized.

Electromagnetic Interference Shielding Performances of MWCNT in Concrete Composites

2017 ◽  
Vol 266 ◽  
pp. 283-286
Author(s):  
Mahadi Sharif ◽  
Chew Sue Ping ◽  
Kin Yuen Leong
Keyword(s):  
Carbon Nanotube ◽  
Electric Field ◽  
Incident Wave ◽  
Electromagnetic Interference ◽  
Network Analyzer ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Electromagnetic Interference Shielding ◽  
Emi Se ◽  
Shielding Material

Carbon nanotube (CNT) acts as electromagnetic interference shielding material in concrete composites was presented in this paper. Three concrete samples respectively with different CNT contents were casted and experimentally tested their shielding effectiveness (SE). The SE measurements which were obtained in function of frequency were taken using vector network analyzer (VNA) in the frequency range of 2.4 - 4.0 GHz. The experimental results showed that the CNT contributes to change in conductivity due to the positioning of the electric field of the incident wave and thus, produces different shielding performances. The EMI SE of concrete composites is improved up to 41dB with CNT concentration of 1.5-2.0 wt%.

scholarly journals Light-Weight Multi-Walled Carbon Nanotube Buckypaper/Glass Fiber-Epoxy Composites for Strong Electromagnetic Interference Shielding and Efficient Microwave Absorption

2021 ◽  
Author(s):  
Bruno Ribeiro ◽  
Newton Adriano Gomes ◽  
Mirabel Cerqueira Rezende
Keyword(s):  
Carbon Nanotube ◽  
Glass Fiber ◽  
Electromagnetic Interference ◽  
Emi Shielding ◽  
Electromagnetic Interference Shielding ◽  
Multi Walled Carbon Nanotube ◽  
X Band ◽  
Potential Applications ◽  
Emi Se ◽  
Minimum Reflection Loss

Abstract Multi-walled carbon nanotube buckypaper (BP) reinforced glass fiber-epoxy (GF/EP) composites were selected to fabricate electromagnetic interference (EMI) shielding and microwave absorbing composites. Six different composite configurations with 3.0 mm thick have been conceived and tested over the X-band (8.2-12.4 GHz). Flexible and low density (0.29 g/cm3) BP provided a high specific EMI SE of 55 dB with controlled electrical conductivity. GF/EP/BP111 and GF/EP/BP101 composites possess EMI SE as high as of 50-60 dB, which can be attributed to the number of BP inserted and variation in the wave-transmitting layer of the laminates. Furthermore, the shielding mechanism was discussed, and it suggested that the dominant contribution to EMI SE was absorption. GF/EP/BP110 laminate demonstrated suitable EMI performance (~20 dB) and excellent microwave performance, achieving an effective -10 dB bandwidth of 3.04 GHz and minimum reflection loss (RL) value of -21.16 dB at 10.37 GHz. On the basis of these results, GF/EP/BP composites prepared in this work have potential applications as both EMI shielding and microwave absorber materials given their facile preparation and lightweight use.

scholarly journals An advancement in the synthesis of unique soft magnetic CoCuFeNiZn high entropy alloy thin films

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chokkakula L. P. Pavithra ◽  
Reddy Kunda Siri Kiran Janardhana ◽  
Kolan Madhav Reddy ◽  
Chandrasekhar Murapaka ◽  
Joydip Joardar ◽  
...  
Keyword(s):  
Thin Films ◽  
Saturation Magnetization ◽  
Functional Materials ◽  
Single Step ◽  
High Entropy Alloy ◽  
High Saturation Magnetization ◽  
Soft Magnetic ◽  
High Entropy ◽  
High Saturation ◽  
Electrochemical Approach

AbstractDiscovery of advanced soft-magnetic high entropy alloy (HEA) thin films are highly pursued to obtain unidentified functional materials. The figure of merit in current nanocrystalline HEA thin films relies in integration of a simple single-step electrochemical approach with a complex HEA system containing multiple elements with dissimilar crystal structures and large variation of melting points. A new family of Cobalt–Copper–Iron–Nickel–Zinc (Co–Cu–Fe–Ni–Zn) HEA thin films are prepared through pulse electrodeposition in aqueous medium, hosts nanocrystalline features in the range of ~ 5–20 nm having FCC and BCC dual phases. The fabricated Co–Cu–Fe–Ni–Zn HEA thin films exhibited high saturation magnetization value of ~ 82 emu/g, relatively low coercivity value of 19.5 Oe and remanent magnetization of 1.17%. Irrespective of the alloying of diamagnetic Zn and Cu with ferromagnetic Fe, Co, Ni elements, the HEA thin film has resulted in relatively high saturation magnetization which can provide useful insights for its potential unexplored applications.

scholarly journals Interface Engineered Microcellular Magnetic Conductive Polyurethane Nanocomposite Foams for Electromagnetic Interference Shielding

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Guolong Sang ◽  
Pei Xu ◽  
Tong Yan ◽  
Vignesh Murugadoss ◽  
Nithesh Naik ◽  
...  
Keyword(s):  
Electromagnetic Interference ◽  
Magnetic Loss ◽  
Interfacial Polarization ◽  
Conductive Network ◽  
Shielding Effectiveness ◽  
Electromagnetic Interference Shielding ◽  
Multiple Reflections ◽  
Conduction Loss ◽  
Composite Foams ◽  
Emi Se

Abstract Lightweight microcellular polyurethane (TPU)/carbon nanotubes (CNTs)/ nickel-coated CNTs (Ni@CNTs)/polymerizable ionic liquid copolymer (PIL) composite foams are prepared by non-solvent induced phase separation (NIPS). CNTs and Ni@CNTs modified by PIL provide more heterogeneous nucleation sites and inhibit the aggregation and combination of microcellular structure. Compared with TPU/CNTs, the TPU/CNTs/PIL and TPU/CNTs/Ni@CNTs/PIL composite foams with smaller microcellular structures have a high electromagnetic interference shielding effectiveness (EMI SE). The evaporate time regulates the microcellular structure, improves the conductive network of composite foams and reduces the microcellular size, which strengthens the multiple reflections of electromagnetic wave. The TPU/10CNTs/10Ni@CNTs/PIL foam exhibits slightly higher SE values (69.9 dB) compared with TPU/20CNTs/PIL foam (53.3 dB). The highest specific EMI SE of TPU/20CNTs/PIL and TPU/10CNTs/10Ni@CNTs/PIL reaches up to 187.2 and 211.5 dB/(g cm−3), respectively. The polarization losses caused by interfacial polarization between TPU substrates and conductive fillers, conduction loss caused by conductive network of fillers and magnetic loss caused by Ni@CNT synergistically attenuate the microwave energy.

scholarly journals A Healable and Mechanically Enhanced Composite with Segregated Conductive Network Structure for High-Efficient Electromagnetic Interference Shielding

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Ting Wang ◽  
Wei-Wei Kong ◽  
Wan-Cheng Yu ◽  
Jie-Feng Gao ◽  
Kun Dai ◽  
...  
Keyword(s):  
Electromagnetic Interference ◽  
Diels Alder ◽  
Electrostatic Attraction ◽  
List Type ◽  
Shielding Effectiveness ◽  
Emi Shielding ◽  
Electromagnetic Interference Shielding ◽  
Elongation At Break ◽  
High Efficient ◽  
Emi Se

Highlights The cationic waterborne polyurethanes microspheres with Diels-Alder bonds were synthesized for the first time. The electrostatic attraction not only endows the composite with segregated structure to gain high electromagnetic-interference shielding effectiveness, but also greatly enhances mechanical properties. Efficient healing property was realized under heating environment. Abstract It is still challenging for conductive polymer composite-based electromagnetic interference (EMI) shielding materials to achieve long-term stability while maintaining high EMI shielding effectiveness (EMI SE), especially undergoing external mechanical stimuli, such as scratches or large deformations. Herein, an electrostatic assembly strategy is adopted to design a healable and segregated carbon nanotube (CNT)/graphene oxide (GO)/polyurethane (PU) composite with excellent and reliable EMI SE, even bearing complex mechanical condition. The negatively charged CNT/GO hybrid is facilely adsorbed on the surface of positively charged PU microsphere to motivate formation of segregated conductive networks in CNT/GO/PU composite, establishing a high EMI SE of 52.7 dB at only 10 wt% CNT/GO loading. The Diels–Alder bonds in PU microsphere endow the CNT/GO/PU composite suffering three cutting/healing cycles with EMI SE retention up to 90%. Additionally, the electrostatic attraction between CNT/GO hybrid and PU microsphere helps to strong interfacial bonding in the composite, resulting in high tensile strength of 43.1 MPa and elongation at break of 626%. The healing efficiency of elongation at break achieves 95% when the composite endured three cutting/healing cycles. This work demonstrates a novel strategy for developing segregated EMI shielding composite with healable features and excellent mechanical performance and shows great potential in the durable and high precision electrical instruments.

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