Design of multiple-layer microwave absorbing structure based on rice husk and carbon nanotubes

Lee, Yeng Seng; Wee, F. H.; Rahim, Hasliza A.; Abdulmalek, Mohamedfareq; You, Yan-bin; Liyana, Z.; Ezanuddin, A.A.M.

doi:10.1007/s00339-016-0618-2

Cited by 23 publications

(12 citation statements)

References 19 publications

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“…The impedance transition between the layers in such a material is typically gradual so that the reflection is reduced. This requires that the front interface with air must be of a low loss material and the material for the following layer must be lossier than the previous layer 3 . For a double-layer microwave absorber, the input impedance Z in can be calculated according to the following equation 51 : where d 1 , d 2 , ε 1 , ε 2 , µ 1 , and µ 2 are the thicknesses, relative complex permittivity, and complex permeability of Layers 1 and 2, respectively.…”

Section: Loss Tangent From the Complex Permeability And Permittivitymentioning

confidence: 99%

A Study on Microwave Absorption Properties of Carbon Black and Ni0.6Zn0.4Fe2O4 Nanocomposites by Tuning the Matching-Absorbing Layer Structures

Ibrahim

Матори

Ismail

et al. 2020

Sci Rep

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Microwave absorption properties were systematically studied for double-layer carbon black/epoxy resin (cB) and ni 0.6 Zn 0.4 fe 2 o 4 /epoxy resin (F) nanocomposites in the frequency range of 8 to 18 GHz. The ni 0.6 Zn 0.4 fe 2 o 4 nanoparticles were synthesized via high energy ball milling with subsequent sintering while carbon black was commercially purchased. The materials were later incorporated into epoxy resin to fabricate double-layer composite structures with total thicknesses of 2 and 3 mm. The CB1/F1, in which carbon black as matching and ferrite as absorbing layer with each thickness of 1 mm, showed the highest microwave absorption of more than 99.9%, with minimum reflection loss of −33.8 dB but with an absorption bandwidth of only 2.7 GHz. Double layer absorbers with F1/CB1(ferrite as matching and carbon black as absorbing layer with each thickness of 1 mm) structure showed the best microwave absorption performance in which more than 99% microwave energy were absorbed, with promising minimum reflection loss of −24.0 dB, along with a wider bandwidth of 4.8 GHz and yet with a reduced thickness of only 2 mm.In order to address issues induced by high proliferation of electromagnetic interferences in both civil and military applications, efficient microwave absorbers are becoming highly desirable and necessary. For that reason, such material is required to effectively reduce the reflection of electromagnetic (EM) signals over a broad absorption bandwidth. In order to improve the performance of microwave absorption properties, microwave absorbers are designed to meet the specific requirements of simultaneously having strong absorption, wide frequency band, lightweight and small thickness. Improvements can certainly be made to the designs by physical assembling of different types of absorbents 1-5 , chemical decorated absorbents 6,7 as well as by designing multi-layer structures [8][9][10][11] .Microwave absorbers are produced using different kinds of materials including one dimensional (1D) materials such as carbon nanotubes 12-15 , two dimensional (2D) materials such as graphene 16,17 and bulk three dimensional (3D) materials such as ferrites 9,18-21 . The difference in the dimensional structure of the materials would largely affect the microwave absorption performances since different kinds of structures contribute to different www.nature.com/scientificreports www.nature.com/scientificreports/ the F1/CB1 sample showed the best all round performance, in which more than 99% microwave energy was absorbed, with a reflection loss of −24.0 dB and a widest bandwidth of 4.8 GHz at −10 dB, yet it is the thinnest among the three designs, having a total thickness of only 2 mm.

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Section: Loss Tangent From the Complex Permeability And Permittivitymentioning

confidence: 99%

A Study on Microwave Absorption Properties of Carbon Black and Ni0.6Zn0.4Fe2O4 Nanocomposites by Tuning the Matching-Absorbing Layer Structures

Ibrahim

Матори

Ismail

et al. 2020

Sci Rep

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“…Moreover, agricultural waste is abundantly available and possesses good microwave absorption properties. EM absorbers based on agricultural waste includes the likes of rice husk [57], [58], sugar cane bagasse [59], dried banana leaves [60] and etc, have exhibited promising absorption rates.…”

Section: Green Material-based Composites Absorbersmentioning

confidence: 99%

“…Different percentages of rubber tire dust and rice husk were investigated and the result showed that the highest percentage of rubber tire dust had the best reflection loss. In addition to that, the performance of rice husk and carbon nanotubes were used to design multilayered flat microwave absorbers in [58]. Such structure resulted in a microwave absorption (or reflection loss) of more than −20 dB.…”

Section: Green Material-based Composites Absorbersmentioning

confidence: 99%

Green Nanocomposite-Based Metamaterial Electromagnetic Absorbers: Potential, Current Developments and Future Perspectives

et al. 2020

Self Cite

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The use of the natural materials instead of conventional materials as electromagnetic absorbers promotes environmental sustainability, cost-effectiveness, and ease of accessibility. Furthermore, these materials may also be designed as absorbers and as reinforcements in building materials in a lightweight form. The absorbing ability of composite materials can be customized based on the chosen fillers. Specifically, magnetic and dielectric fillers can be incorporated to improve the absorption of a composite material compared to traditional materials. This work aims to review recent developments of electromagnetic absorbers enabled by nanocomposites, metamaterial and metasurface-based, as well as green composite alternatives. First, the background concepts of electromagnetic wave absorption and reflection will be presented, followed by the assessment techniques in determining electromagnetic properties of absorbing materials. Next, the stateof-the-art absorbers utilizing different materials will be presented and their performances are compared. This review concludes with a special focus on the future perspective of the potential of metamaterial based nanocellulose composites as ultrathin and broadband electromagnetic absorbers. INDEX TERMS Electromagnetic, microwave absorber, nanocomposites, metamaterial, nanocellulose. I. INTRODUCTION In recent years, the development of wireless technologies with the particular aim at achieving higher communication throughput and wider bandwidths for high-speed communication have been developed rapidly to accommodate consumers' needs. However, the wide use of wireless communication systems has also resulted in an increasing electromagnetic interference (EMI) to the environment. The conducted or radiated electromagnetic signals interferes with The associate editor coordinating the review of this manuscript and approving it for publication was Kuang Zhang.

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“…For instance, CNTs offer favourable EM characteristics such as good microwave absorption and high-electrical conductivity [22][23][24]. The high amount of carbon content in CNTs increases its dielectric properties and radiation absorption, thus decreasing the reflectivity of the microwave absorbers [25]. Besides being a lightweight absorbing material, its effective dielectric constant and loss factor can be combined with RHs to form a composite (denoted as RH + CNT) and optimised with a suitable geometry to form such broadband microwave absorbers.…”

Section: Introductionmentioning

confidence: 99%

Enhanced microwave absorption of rice husk‐based pyramidal microwave absorber with different lossy base layer

Lee

Soh

You

et al. 2020

IET Microwaves, Antennas & Propagation

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The size of pyramidal microwave absorbers (PMA) is one of the main considerations for their selection for use in anechoic chambers. In this work, a new type of PMA is introduced, with rice husk (RH) as its filler. Meanwhile, a lossy base layer is also introduced in the PMA using a combined RH and carbon nanotube (CNT) composite. To do so, the dielectric properties of the RH‐CNT composite are first investigated from 2–18 GHz by using a dielectric probe. Next, the microwave absorption properties of the PMA were investigated in terms of different height of the pyramidal structure and base layer. The free‐space method was used to measure the microwave absorption of PMA at oblique incident angles of 0° to 60°, respectively. Results indicated good microwave absorption characteristics in the 2–6 GHz with a height of 11.5 cm the PMA structure, and 1 cm thickness of the base layer. The lossy base layer is found to increase the bandwidth of the absorber and improve the microwave absorption of PMA in the lower GHz frequencies. Further investigations concluded that the microwave absorption performance of the PMA is dependent on its dielectric properties, size and base layer.

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Design of multiple-layer microwave absorbing structure based on rice husk and carbon nanotubes

Cited by 23 publications

References 19 publications

A Study on Microwave Absorption Properties of Carbon Black and Ni0.6Zn0.4Fe2O4 Nanocomposites by Tuning the Matching-Absorbing Layer Structures

A Study on Microwave Absorption Properties of Carbon Black and Ni0.6Zn0.4Fe2O4 Nanocomposites by Tuning the Matching-Absorbing Layer Structures

Green Nanocomposite-Based Metamaterial Electromagnetic Absorbers: Potential, Current Developments and Future Perspectives

Enhanced microwave absorption of rice husk‐based pyramidal microwave absorber with different lossy base layer

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