Sage Journals: Discover world-class research

Abstract

The range and strength of Electromagnetic Wave loss are increasing with the development of electronic technology in intellectualization and diversification. Extensive research is focused on high-frequency microwave absorbersbut rarely on low-frequency ones. However, the shield of low-frequency microwave interference is bulky and complicated. It is necessary to adopt new structural composites with lightweight, porous, or multi-layer magneto-dielectric synergistic to obtain lighter, thinner, broader bandwidth, and strong absorption absorbers in the low-frequency range. The porous and multi-layer textiles would extend the Microwave (M. W.) transmitting pathway. The prepared M. W. textile-based composites possess broad bandwidth and strong absorption in the low-frequency range when magneto-dielectric synergistic functional particles have embedded in the textiles. This paper reviewed the modified graphene-based absorbers (GBAs), the hybrids combined GBAs with the low-frequency magnetic loss absorbers (LFMLAs), and the textile-based composites added by the complex combined GBAs with LFMLAs (GBAs/LFMLAs). The prepared GBAs/LFMLAs textile-based composites are broad bandwidth, lightweight, small thickness, and strong absorption materials in the low-frequency range. The prepared GBAs/LFMLAs textile-based microwave absorbers (MWAs) may expand the application scope of MWAs and promote their economic benefit. The GBAs/LFMLAs textile-based composites may propose a new strategy of broad bandwidth MWAs in the low-frequency range.

Keywords

low-frequency absorbing range broad bandwidth graphene-based absorbers low-frequency magnetic loss absorbers magneto-dielectric synergistic textile-based composites

Introduction

With the rapid development of information technology, electronics' high-speed calculation and transmitting rate are becoming increasingly important. The Electromagnetic Wave (EMW) interference and shielding frequency range expands constantly. With complicated modern battlefield conditions, radar detection systems are simultaneously exposed to EMW interference. Besides, the civilian and military applications suffer from the booming EMW interference as well, such as R.F.,¹ radar stealth technology,² national defense security,³ portable transmission,⁴ and electronic devices.⁵ Therefore, military and civilians suffer from the booming EMW interference due to upgrading continuous communication technology.

However, the absorbing frequency range appears to “blueshift” to the low-frequency range gradually, as shown in Figure 1.^6–8 Therefore, the nature of the microwave absorbers should be broad bandwidth, as well as lightweight, small thickness, strong absorption, excellent stability, appropriate flexibility, and physical compatibility in the low-frequency range.⁹

Figure 1.

(a) Common definition of electromagnetic spectrum ranges of the corresponding frequency bands. (b) Various microwave and terahertz devices are widely applied in modern society.⁸

The high-frequency (>8 GHz) absorbing technology has been relatively mature, while the low-frequency absorbing technology (<8 GHz) with long propagation distance, strong penetration ability, and poor shielding suffers from great difficulties and needs to be solved urgently.^6,7 The microwave absorbing textile-based composites are widely used because of their excellent absorption and characteristics, such as lightweight, remarkable plasticity, flexibility, and low cost.^8,9

Generally, the absorption of common textiles is not outstanding. Functional particles with magnetic loss and/or dielectric loss are introduced directly or through transparent materials to the textiles. The textile-based composites possess the function of magnetic loss and/or dielectric loss. When the hybrids that the magnetic loss particles are combined with the dielectric loss particles in optimized ratios, namely the magneto-dielectric synergistic composites, the electromagnetic wavelength absorption is remarkable.^10–12

The traditional MLAs include ferrite, magnetic metal particles, and their alloys. However, using a single absorber (MLA) has many limitations, such as its considerable thickness, heavyweight, narrow Effective Absorption bandwidth(EAB), and weak absorption. The traditional Dielectric Loss absorbers(DLAs) include conductive polymers, ceramic-based materials, Mxene, and chiral materials,carbon-based materials such as carbon nanotube (CNT), Graphene (G.N.), ppy and polythiophene (PTh).^13–16

Graphene (G.N.), an excellent dielectric loss material, has attracted much attention due to its high strength, good toughness, lightweight, medium dielectric constant, and electrical tunability with frequency.^17–19 There are interactive phenomena between the reduced Graphene Oxide (rGO) and wool/nylon (W/N) fabric, as shown in Figure 2. In textile-based composites, the depositing of rGO can construct a three-dimensional electronic transmitting channel network within the W/N textile. Therefore, they can be excellent E. M. textile-based composites.¹⁸

Figure 2.

The preparation process of the GBAs-based wool/nylon (W/N) composite.¹⁸

In MWA textile-based composites, textiles often have two roles. One of them is to be a reinforcement providing all the mechanical properties of the composite. The reinforcement textile is then coated²⁰ or printed²¹ by MLAs or/and DLAs function particles that are diffused in the transparent resin^22,23 in the formation process. In this role, the textile can not attenuate any EMW energy. The second role of the textile is to promote the absorption of the MWAM.^24,25 For example, carbon fiber,²⁶ glass fiber,²⁷ and metal and metal alloy fiber, such as Ni,²⁸ can consume the electronic or magnetic component of the MWAM. The functional fiber of textiles would prolong the pathway of the M.W. Therefore, textiles can promote the absorption of the absorber.^29,30

The absorbing mechanism of the Microwave Absorbing Materials (MWAMs)

The absorbing mechanism of MWAMs is not only related to their intrinsic performance, but also their structure, such as the electric resonance,³¹ ferro-resonance,³² and mono-layered,³³ double-layered,³⁴ multi-layered,³⁵ and meta-material.^36,37

In the propagation process, the Microwave (M.W.) penetrates the front surface of the MWAMs, as shown in Figure 3.⁷ The incident microwave can be divided into three parts: the absorption wave, the reflection wave, and the transmitting wave. When the absorption of MWAMs enhances, the reflection of M.W. and the transmitting M.W. to the spatial will be reduced, which may be an effective shielding method for EMW.³⁸

Figure 3.

The propagation process of EMW.⁶

Two points should be achieved to promote the absorption of the MWAM. Firstly, it is necessary to make an excellent impedance match between MWAM and M.W. When the M.W. propagates in the MWAM, creating a pathway long enough to transfer the M.W.’s energy is essential. Secondly, there should be an ability to dampen the M.W. and convert the energy of M.W. into thermal energy or other forms of energy.^39,40

According to the propagation process of EMW, the possible schemes to achieve excellent absorption can be discussed as follows: (1) improving the impedance match between MWAM and M.W. so that M.W. enter the MWAM smoothly, (2) the porous or multi-layered structures are formed inside the MWAM, which make the transmitting pathway of M.W. curve and long, (3) the MWAM have powerful M.W. attenuation ability to consume the M.W. Thereby, the absorption of MWAM may be promoted.^40–43

Two conditions must be met simultaneously to implement both broad bandwidth and strong absorption of the MWAM in the low-frequency range. The two conditions are the remarkable impedance match ability and the exceptional M.W. absorbing ability.⁴⁴

To meet the two conditions above, the constituent component of MWAM must have the capability of magnetic loss or/and dielectric loss in the low-frequency range. Among the MWAMs, the electrical loss material consumes the electric component of M.W., and the magnetic loss material consumes the magnetic component of M.W. in the low-frequency range. When the GBAs/MLAs hybrids have the magneto-dielectric synergistic resonance in some overlap frequency range, the absorbing ability of MWAMs should be enhanced in the corresponding frequency range. The combination of the magneto-dielectric synergistic hybrids with porous or multi-layered textiles will expand the application scope of textile-based MWAMs.^45–48

Graphene-based absorbers (GBAs) with dielectric loss

Carbon-based materials have the advantage of low cost compared with other dielectric loss materials, as shown in Table 1. Besides, the carbon-based materials have other excellent performances, such as the large specific surface area, high strength/weight ratio, lightweight, high mechanical strength, thermal stability, electrical loss frequency-tunable, and excellent corrosion resistance. They can be prepared as perfect porous absorbers, such as porous carbon nanowire, porous carbon nanofiber, carbon nanotube, and graphene networks.^49,50 Graphene (G.N.), a high-quality carbon-based material, has excellent compatibility with other polymers, which can be acted as an M.W. absorber or M.W. isolation material.^51,52

Table 1.

The characteristics and classification of the absorbers.^49–52

Categories	Low density	Broad bandwidth	Strong absorption	High mechanical performance	Low cost	Thermal and chemicalstabilities
Dielectric
Conductive polymers	√	×	×	√	×	×
Carbon-based	√	×	×	√	√	√
Ceramics	√	×	×	√	×	√
Chiral materials	√	√	√	√	×	×
Mxene	√	√	√	×	×	×
Magnetic
Ferrite	×	×	√	×	√	×
Metal power	×	√	√	×	×	×
Metal oxide	×	√	√	×	√	×
Metal alloy powder	×	×	√	×	×	×
Micro-nano metal particles	×	√	√	×	×	√

Cao and co-workers⁵³ demonstrated that the M.W. reflection loss value(RLV) of rGO is −6.9 dB at 7 GHz, which was higher than that of carbon nanotube and graphite.

Rubric and co-workers⁵⁴ added G.N. to the epoxy resin to study their dielectric loss performance and absorption of their hybrid. The effects of particle size (3 μm, 6–8 μm, 15 μm) and mass ratio (5%–25%) were studied and discussed. The results demonstrated that the sample with the smallest G.N. particle size (3 μm) and the highest weight ratio (25 wt%) exhibited high loss tangent (tan δ = 0.36) and medium dielectric constant (ε' = 12–14) in the frequency range of 8–10 GHz.

In summary, pure graphene (G.N.), acting as an absorber, has a medium dielectric constant, which is suitable for the medium and/or high-frequency MWAM. Although the absorbing strength of G.N. is higher than that of carbon nanotube and graphite, the optimal RLV was just −6.9 dB. The RLV of pure G.N. is greater than −10 dB, which indicates that the pure G.N. fails to implement effective absorption(generally, the effective absorption reflection loss value is less than −10 dB). The reason may be that the G.N. molecule is a 2D crystal macro-molecule composed of a tightly packed carbon layer, as shown in Figure 4(a). There is almost no gap among G.N. molecules and small gaps between their valence and conduction bands in the molecule. In this way, it is easy to cause the pure G.N. to accumulate and poor impedance match with spatial. Thereby, the absorption of the pure G.N. is limited.^55,56

Figure 4.

(a).The 2D crystal macro-molecule structure of G.N.³⁶ (b). Four types of N atoms exist in NGN,⁴⁵ (c).The morphology structure of 3D GBAs.⁵⁶

To improve the absorption of G.N., researchers modified it to improve its natural resonance, heterogeneous structure interface, and electromagnetic coupling, which may improve the impedance match and enhance the absorption. The modification of pure G.N. is inevitable. The modified G.N. will represent for GBAs with lightweight, small thickness, and strong absorption.⁵⁷

Modification of the molecular structure of G.N

Introducing heteroatoms (such as N, B, F, S, P, I), transition metal ions and rare-earth atoms to the surface or the edge of G.N. molecules induces gaps between or among G.N. molecules. The process of introducing atoms to G.N. was named doping, which results in the gaps between the valence and conduction bands opening and the molecular structure flattening. The doping of G.N. reduces the constant effectively. Among the doping atoms, the N atom is the most appropriate dopant for the G.N. molecule. The doped product was named as nitrogen-doping graphene(NGN).^58–61

The introduction of the N atom to the G.N. makes the C atom polarize and brings about the lattice changes, which prompts energy transition from the contiguous state to the Fermi level,^62,63 and the electrons' transporting speeds up. Furthermore, the molecules are not accessible to self-agglomerate. In addition, introducing the N atom causes more structural defects and additional polarization relaxation in the G.N. molecule, which improves the impedance match between the MWAM and the spatial. Therefore, the nitrogen-doping Graphene (NGN) is more suitable as a dielectric loss absorber than pure G.N., as shown in Figure 4(b). There are four types of N atom existing in the NGN molecule: pyridinic N atom, amino N atom, pyrrolic N atom, and graphite N atom.^64–69

Quan and co-workers⁷⁰ synthesized the NGN with precursors graphene oxide (G.O.) and urea by a facile hydrothermal method. The pyrrolic-N of NGN has been found to dominate the induced magnetic performance, which cooperates with the dielectric loss, and the NGN was conducive to absorption. The optimized RLV of NGN achieved −11.3 dB at 12.7 GHz, and the Effective Absorption Bandwidth (EAB) is 12.2–14.3 GHz with a thickness of 3 mm. Furthermore, the density of NGN is proved more favorable than other existing GBAs.

Zhou and co-workers⁷¹ synthesized NGN nanosheets through the in-situ strategy. The NGN reduced the dielectric constant and solved the interface impedance mismatch problem. The results demonstrated that the NGN nanosheet with 4.6% nitrogen-doping showed an excellent absorption compared to the pure G.N. nanosheet. More than 99% of the M. W. could be quantitatively attenuated in 5–18 GHz by the NGN.

Chamoli and co-workers⁷² synthesized the NGN sheet by solvothermal. The results demonstrated that the presence of the N atom generates defects in G.N. molecular, which enhance the overall electrical properties of NGN. The prepared nano-NGN/epoxy resin composites were used to study the M. W. response. The results proved that the minimal RLV is −40.8 dB when the mass fraction of NGN is 2%, and the EAB (R.L. <−10 dB) is 1.5 GHz.

In summary, the RLV of NGN is 5 times that of pure G.N., and both the EAB and impedance match are improved. It may benefit from the introduction of the N atom to the G.N. lattice. The N atom induces the G. N. lattice defects, which prompt the polarizations of the G. N. system, such as dipole polarization, dielectric polarization, interface polarization, and defect polarization. Furthermore, the crystallinity is reduced automatically. The parameter optimization of the lattice resulted in a decrease in conductivity and the reduction of the dielectric constant. A better balance between attenuation loss and impedance match is implemented with the N atom doping in the G. N. molecular. It can be seen that the nitrogen-doping in the G. N. may improve the absorption and the impedance match.

Modification of the morphology structure of G.N

Graphene can be used as a dielectric absorber due to its unique intrinsic properties, such as specific surface area conductivity, dielectric loss, and low density and molecular morphology, which significantly influence the absorption of G.N.⁷³ The flexible 2D structure of G.N. can be assembled among nanosheets to form a multi-level sandwich-like structure or a 3D porous network structure. The huge cross-linking network makes the M.W. interaction inside the G.N., such as multiple reflections and scattering capacitor, and the long and complicated M.W. transmitting pathway contribute to the attenuation of the incident M.W.⁷⁴ Besides, the 3D porous G.N. has low density, large specific surface area, high conductivity, and high intensity, as shown in Figure 4(c).⁷⁵

Chen and co-workers⁷⁶ prepared potent M.W. absorbing hybrids constituted by the multi-walled carbon nanotube (MWCNT) and porous graphene foam (G.F.). They analyzed the properties of the composites with C atom G.F.s (CGFs) and without C atom (C@GFs) under different conditions, such as different mass ratios and annealing temperatures. The results demonstrated that the EAB of C@GFs is narrower than that of CGFs in the low-frequency microwave range. When the annealing temperature is 200°C, the absorption of GCF-200 is better than that of other members. The minimal RLV of GCF-200 is −32.5 dB at 4.5 GHz with a thickness of 2 mm, and the EAB is 2–18 GHz.

Shu and co-workers⁷⁷ prepared a 3D network graphene (3DNG) by hydrothermal self-assembly and high-temperature calcination. The 3DNG was synthesized by precursors nitrogen-doping rGO and MWCNT. The results demonstrated that the absorption of 3DNG improved significantly with the increase in calcination temperature. When the calcination temperature was 600°C, and the mass content was 8 wt%, the minimal RLV of 3DNG₆₀₀ was −69.6 dB at 12.5 GHz with a thickness of 1.5 mm, and the EAB was 4.3 GHz (13.2–17.5 GHz).

Zhang and co-workers⁷⁸ prepared a series of graphene foams (G.F.s) through solvothermal and annealing. In the analysis of the G.F.s, it appeared that with the increase of annealing temperature, the number of porous was up at first, then down, and the penetrating M.W. propagated along the porous wall, then the E.M. energy dissipated significantly. Among the G.F.s, the minimal RLV of the GF-T₆₀₀ (the annealing temperature was 600°C) or C_0.6(the initial concentration of G.N. was 0.6 mg/mL) was −34.0 dB, and the EAB was 14.3 GHz. Besides, the bulk density of GF-T₆₀₀ was an ultralow value of 1.6 mg/cm³, close to ambient air density (1.2 mg/cm³).

In summary, the 3D networked structure improves the RLV and the EAB of G. N., which is conducive to both the absorption strength and bandwidth. The reason may be as follows:① the networked structure of 3DNG increases the specific surface area, which increases the absorbing capacity of M.W.; ② a long and complicated electronic transmitting pathway of M.W. is formed, which makes the M.W. penetrate the inside of the MWAM and transmit along the porous wall. Thereby, the porous 3DNG could prolong the transmitting distance of M.W. and enhance its attenuation; ③ the attenuation ability of M.W. is promoted by the characteristic multi-level structure. And there are a series of attenuation mechanisms inside the 3DNG, such as magnetic resonance, interface polarization, relaxation polarization, and dipole polarization. Therefore, modified 3D networked structures of G.N. are conducive to the high-quality and lightweight absorber.

Modification of the supramolecular structure of G.N.

The researchers developed two-layer G.N.s by tearing and stacking. A two-layer or tetra-layer G.N. structure was composed of one or two AB-stacked G.N. bilayers with a relative rotation angle.⁷⁹ Namely, there were one or two stacks in the G.N. lattice. Under the action of the E.M. field, the G.N. molecular layers could be twisted at a certain angle, which was defined as Magic Angle. So far, there have been two kinds of G.N. available: twisted double-layer Graphene (TBG) and twisted double bilayer graphene (TBG),^80,81 as shown in Figure 5(a) and (b).

Figure 5.

(a) Schematic drawing of the twisted double bilayer graphene configuration investigated in our work. The intrinsic symmetric polarization is illustrated. (b) Reciprocal lattice (black dots) and the mini-Brillouin zone (gray hexagon) of θ = 21.8° (m = 1) TDBG. The blue and red hexagons are the Brillouin zones of the corresponding A. B. stacked BLG counterparts.⁶⁴

Zhang,⁸¹ Shen,⁸²and FateMeh⁸³ and their co-workers researched the TBG and TDBG. The results demonstrated that lattice modification made the G. N. amorphous to be flat conduction band at the Magic Angle θ = 21.8°. Therefore, separating the conduction bands among TBG or TDBG molecules was easy and conducive to inter-molecular filling and doping. Compared with pure G. N., the TBG and TDBG are easier to form structures with a large aspect ratio. However, these two materials are rarely used in actual production because of their novelty, low output, and high cost. However, they are used in theoretical research generally, such as modeling and simulation. Therefore, they are seldom used in the field of MWAM.

The hybrid of GBAs/MLAs functional particles in the low-frequency range

The modified GBAs can improve their frequency-tunable dielectric loss capacity, and the attenuation of the overall electrical component of the EMW is excellent. However, the attenuation ability of the magnetic component of the EMW is weak. To implement a broad bandwidth and strong absorption of GBA in the low-frequency range, the introduction of a complementary magnetic loss component is inevitable.^7,84–86 The EMW loss capacity of MWAM decreases with an increasing frequency, especially in the low-frequency range. Hence, improving the EMW loss capacity of MWAM is imperative, especially the absorbing capacity.⁸⁷ However, higher dielectric loss is not conducive to impedance match in the low-frequency range. Therefore, the robust absorption in the low-frequency range mainly depends on the ability of magnetic loss.^32,88

Traditional magnetic loss materials commonly include ferrite, metal, and metal alloys.⁸⁹ The ferrite can implement low-frequency absorption, but the bandwidth is narrow, the saturation magnetization intensity is poor, and the thickness is large also. Magnetic metals have excellent high-frequency magnetic resonance, which is suitable for high-frequency EMW absorption. However, the usage of magnetic metal and the metal alloy is limited in the low-frequency range because of their high density, poor chemical corrosion, and narrow EAB. The structure of micro-nano magnetic metal particles is relatively simple, and there are no magnetic moments between magnetic sub-grids canceling each other out. Their permeability and saturation magnetization are significant and can be modified to be micro-nano magnetic alloys to adjust their frequency response. The low-frequency absorption is improved when the micro-nano magnetic loss absorber and its alloys are combined with the dielectric loss GBAs. Therefore, the micro-nano magnetic loss absorbers are suitable for low-frequency MWAM.^85,87,89

Ma and co-workers⁹⁰ synthesized reduced Graphene oxide/ZnFe₂O₄/Ni (rGO/ZnFe₂O₄/Ni) spherical nano-hybrid composites by hydrothermal strategy. When the content of rGO/ZnFe₂O₄/Ni nano-hybrid increased to 40 wt%, the minimal RLV was −22.57 dB at 4.21 GHz with a thickness of 2.5 mm. The EAB range was 3.6 ∼ 10.22 GHz with a thickness of 1.5 ∼ 4.0 mm. The results demonstrated that the rGO/ZnFe₂O₄/Ni nano-hybrids were robust absorbers in the low-frequency range, which provided a new idea for the lightweight tailing of GAB, as shown in Figure 6.

Figure 6.

The schematic illustration of the fabrication process of rGO/ZnFe₂O₄/Ni nanohybrid.⁹⁰

Francisco and co-workers⁹¹ synthesized a new type of M.W. absorber by Pechini sol-gel strategy. The reduced graphene oxide (rGO) acted as the based material in the system. The Fe @γ-Fe₂O₃ and Fe/Co/Ni alloy were protected by graphene-based nanoparticles (N.P.s), and the magnetic loss materials acted as the decorating material. The results demonstrated that the EBA range was 0.4 MHz–20 GHz, and the absorptivity of the MWAMs was between 60% and 100%, Sun and co-workers⁹² assembled CoNi/G.N. nanocomposite (CoNi/G.N.) by the one-pot strategy. The results demonstrated that the M.W. absorption of CoNi/G.N. was excellent. The minimal RLV was −31.0 dB at 4.9 GHz with a thickness of 4 mm. The EAB was 7.3 GHz with a thickness of 2 mm.

Wan and co-workers⁹³ synthesized a novel γ-Fe₂O₃ nanoring (N.R.)/porous nitrogen-doped graphene (γ- Fe₂O₃ NR/PNG) hybrid with different mass ratios by a two-step solvothermal strategy. The results demonstrated that compared with pure γ-Fe₂O₃ N.R.s or PNG, the γ-Fe₂O₃ NRs/PNG hybrids showed robust M.W. absorption. When the mass ratio of γ- Fe₂O₃ NR: PNG hybrid was 4:1, the EAB (RLV<−10 dB) was most comprehensive. The minimal RLV (RLV_min) value was −40.18 dB at 7.80 GHz with a thickness of 2.5 mm, and the EAB was 3.41 GHz. In addition, the hybrid had excellent absorption in the low-frequency range. The RLV_min was −32.69 dB at 3.38 GHz with a thickness of 5.5 mm.

In summary, when the low-frequency magnetic loss absorbers (LFMLAs) combined with GBAs, the EAB of the hybrids was primary in the low-frequency range with a small thickness. The reasons may be that the LFMLAs play an essential role in the magnetic resonance of the low-frequency range, and the GBAs play the role of electrical frequency-tunable resonance at the corresponding frequency range. When LFMLAs are combined with the GBAs at an appropriate ratio and in a reasonable manner, the LFMLAs consume the low-frequency magnetic component of the M.W., and the GBAs consume the electrical component of the M.W. and improve the impedance match of the hybrids. The GBAs and LFMLAs hybrids resonate synergistically in the low-frequency range. Therefore, the GBAs/LFMLAs hybrids improve the absorption in the low-frequency range.

The GBM/MLA-added textile-based composites

The common textiles have little effect on M.W. absorption.⁹⁴ However, some novel textile-based MWAM impacts the absorption remarkably.¹ The basic unit of the textile-based MWAM, no matter what kind of structure it is.⁹⁵

Fibers can be molded into 1D deposited or coated fibers,⁹⁶ 2D flat textiles,⁹⁷ and 3D cubic fabrics⁹⁸ due to their flexible structure. However, the textile-based composites in the low-frequency range mainly focus on the EMW interference shielding materials but few on the MWAs. For example, Ozen and co-workers⁹⁹ studied the EMI fibers, which blended stainless/polyester fiber with standard polyester fiber in a specified proportion. The results demonstrated that when the ratio of conductive stainless steel fiber was 25% in the nonwoven fabric, the optimal electromagnetic shielding efficiency (EMSE) was 18 dB in the frequency range of 1.2–3 GHz. Zkan and co-workers¹⁰⁰ studied the fibers by blending stainless steel with nylon 66 filament. The results demonstrated that the optimal EMSE was 78.70 dB in the frequency range of 0.8 ∼ 5.2 GHz.

A network with colossal 3D cross-linked and intricate magneton-dielectric synergistic loss is inevitable for obtaining low-frequency textile-based composite. The 3D textile-based composite formed by 1D fiber creates a very long and complex transmission channel for the incident M.W., which reduces the thickness caused by the strong absorption and broad bandwidth of low-frequency MWAM.¹⁰⁰

Song and co-workers³⁰ prepared the textile-based composite by in-situ synthetic. The results demonstrated that the carbonyl iron/reduced Graphene oxide/nonwoven (CI-rGO-NW) textile-based composite had strong M.W. absorption in the low-frequency range (2.91–5.1 GHz), and the EAB was 9.2 GHz, as shown in Figure 7.

Figure 7.

The M.W. loss in the CI-rGO-NW composite.³⁰

Li and co-workers¹⁰¹ introduced 2D rGO into 1D carbon fiber (CF) to synthesize 3D carbon fiber/reduced graphene oxide (CF-rGO) textile-based composite. In the system, zero-dimensional Ni nanoparticles were deposited on the surface of rGO to prepare a lightweight, flexible carbon fiber/reduced graphene oxide/nickel (CF-rGO-Ni) composite. The results demonstrated that rGO and Ni significantly influenced the dielectric parameter and absorption. In addition, CF-rGO and CF-rGO-Ni nano-textile could be low-frequency absorbers by adjusting the proportion and dosage of rGO and Ni, as shown in Figure 8.

Figure 8.

M.W. loss in the CF-rGO-Ni textile-based composite.⁷⁹

In summary, when the low-frequency magneton-dielectric synergist functional particles are added to the textile. The textile-based composite would obtain the corresponding low-frequency loss function. Therefore, the functional particle would cause the textile-based composite to possess low-frequency absorption. In the system, the textile acts as the electronic carrier and constructs the pathway of M.W. transmission. In other words, the network and porous structure in the M.W. loss composite extends the transmitting pathway of the M.W., which attenuates the M.W. energy effectively. Therefore, the magneto-dielectric synergistic textile-based composite would enhance the M.W. absorbing strength and bandwidth.

Conclusions and perspectives

This paper summarizes the modified GBAs, the hybrid constituted by GBAs and LFMLAs, and the textile-based composite added by a hybrid of GBAs/LFMLAs functional particle. In textile-based composite, the GBAs/LFMLAs functional particle hybrid consumes the M.W. energy synergetically, and the textile promotes absorption. In the composite, the lightweight GBAs, which are electric frequency-tunable, undertake as an excellent M.W. absorber of the electric component. At the same time, the LFMLAs take place magnetic resonance in the low-frequency range, consuming the magnetic component of the M.W. . The absorption would be enhanced when the LFMLAs and GBAs resonate synergetically in a similar or overlapping frequency range. The textile added by the GBAs/LFMLAs synergistic functional particle hybrid may prolong the propagation pathway of the M.W., which would enhance the M.W. consumption in the low-frequency range. Finally, the prepared M.W. textile-based composite has excellent properties in the low-frequency range, such as broad bandwidth, lightweight, small thickness, flexibility, and strong absorption.

However, there are some perspectives on the GBAs/LFMLAs textile-based composite of the low-frequency range: (1) carbonyl iron and ferrite are traditional LFMLAs, but there are some deficiencies. More suitable LFMLAs should be developed to replace the defective ones, such as nano-magnetic metal alloys and amorphous/nanocrystalline soft magnetic absorbers. (2) it is difficult to control the amount of N atom in the NGN. The effective control of doping the N atom will be of great significance to the dielectric constant of NGN, which may be a great assistant to the accurate application of NGN; (3) the hybrid modes of magneto-dielectric synergetic functional particle influence the absorption significantly. An excellent solution to this problem will make a remarkable breakthrough in improving absorption. (4) the strategies of adding magneto-dielectric synergetic hybrid to textile influence the absorption and application scope of the composite remarkably. In the future, there should be more popular strategies developed. The low-frequency GBAs/LFMLAs textile-based composite may be widely used in the military and civil scope.

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Wang Aiqiong

Nomenclatures

References

Bokova

Devina

Kovalenko

. Development of multilayer radio-absorbing materials based on nonwoven dielectric matrixes and a polymeric binder. Fibre Chem 2019; 50(5): 462–467.

Fan

Wang

, et al. Ultra-wideband microwave absorber via an integrated metasurface and impedance- matching lattice design. J Phys D-Applied Phys 2019; 52(31): 31LT01.

Meng

Wang

Guo

, et al. Graphene-based microwave absorbing composites: a review and prospective. Composites Part B-Engineering 2018; 137: 260–277.

Guo

Jiang

Wang

, et al. Core-rim structured carbide MXene/SiO2 nanoplates as an ultrathin microwave absorber. Carbon 2020; 169: 214–224.

Kefeni

Msagati

TAM

Mamba

. Ferrite nanoparticles: synthesis, characterisation and applications in electronic device. Mater Sci Eng B-Advanced Funct Solid-State Mater 2017; 215: 37–55.

Santhosi

Ramji

Rao

. Optimization of double layered graphene-based microwave absorber in X-band using Pareto genetic algorithm. Mater Res Express 2019; 6(10): 105610.

Luo

Yang

Gao

, et al. Graphene oxide “Surfactant”-directed tunable concentration of graphene dispersion. Small 2020; 16(45): 2003426.

Delihasanlar

Yuzer

. Wearable textile fabric based 3D metamaterials absorber in x-band. Appl Comput Electromagnetics Soc J 2020; 35(2): 230–236.

Jangra

Maity

Vishnoi

. A review on the development of conjugated polymer-based textile thermoelectric generator. J Ind Textiles 2021; 181S–214S.

10.

Song

Fan

Hou

, et al. A wearable microwave absorption cloth. J Mater Chem C 2017; 5(9): 2432–2441.

11.

Xie

Shui

, et al. Preparation and properties of 3D fabric-gypsum based microwave absorbing materials. Cailiao Daobao/Materials Rev 2018; 32(9): 31233134–31243127

12.

Wang

Liu

Chen

, et al. Tailoring conductive network nanostructures of ZIF-derived cobalt-decorated N-doped graphene/carbon nanotubes for microwave absorption applications. J Colloid Interf Sci 2021; 591: 463–473.

13.

Liu

Zhang

, et al. 3D cross-linked graphene or/and MXene based nanomaterials for electromagnetic wave absorbing and shielding. Carbon 2021; 178: 413–435.

14.

Zhang

Guo

Wang

, et al. Enhanced shielding performance of layered carbon fiber composites filled with carbonyl iron and carbon nanotubes in the koch curve fractal method. Molecules 2020; 25(4): 969.

15.

Akhtar

Boudaghi

, et al. Microwave absorption characteristic of a double-layer X-band absorber based on MWCNTs/La0.6Sr0.4Mn0.5Fe0.5O4 coated with PEDOT polymer. Ceramics Int 2021; 47(12): 17736–17744.

16.

Motamedi

Rahmanifard

Adibi

. Synthesis and microwave absorption characteristics of BaFe12O19/BaTiO3/MWCNT/polypyrrole quaternary composite. Synth Met 2021; 280: 116873.

17.

Zhao

X-M

Liu

Y-J

. Dielectric properties of ferrite/silicon carbide/graphite three-layer composite coating materials. Cailiao Gongcheng/Journal Mater Eng 2017; 45(1): 33–37.

18.

Ghosh

Remanan

Bhattacharjee

, et al. A multifunctional smart textile derived from merino wool/nylon polymer nanocomposites as next generation microwave absorber and soft touch sensor. Acs Appl Mater Inter 2020; 12(15): 17988–18001.

19.

Selvarajan

Hamzah

Majlis

. Electrical characteristics of Graphene-based Field Effect Transistor (GFET) biosensor for ADH detection. In Biosensing and nanomedicine X 2017, 6–7 August 2017, San Diego, CA, USA

20.

Zhu

, et al. Microwave absorption properties of fabric coated absorbing material using modified carbonyl iron powder. Composites Part B-Engineering 2011; 42(4): 626–630.

21.

Momeni-Nasab

Bidoki

Hadizadeh

, et al. Ink-jet printed metamaterial microwave absorber using reactive inks. Aeu-International J Electronics Commun 2020; 123: 153259.

22.

Wang

Huang

, et al. Microwave absorbing properties of composite coating by carbon nanotube and nanoscaled tetrapod-shaped ZnO. Acta Physica Sinica 2010; 59(3): 1946–1951.

23.

Liu

Zhao

Tuo

. The research of E.M. wave absorbing properties of ferrite/silicon carbide/graphite three-layer composite coating knitted fabrics. J Textile Inst 2016; 107(4): 483–492.

24.

D’Aloia

Bidsorkhi

Bellis

, et al. Graphene-based wideband electromagnetic absorbing textiles at microwave bands. Ieee Trans Electromagn Compatibility 2022; 64(3): 710–719.

25.

Zhan

, et al. Preparation and characterization of pu/pet matrix gradient composites with microwave-absorbing function. Coatings 2021; 11(8): 982.

26.

Liu

Tao

Luo

, et al. Preparation and microwave absorbing property of carbon fiber/polyurethane radar absorbing coating. Rsc Adv 2017; 7(73): 46060–46068.

27.

Choi

Kwak

B-S

Kweon

J-H

, et al. Microwave absorbing structure using periodic pattern coated fabric. Compos Structures 2020; 238: 111953.

28.

Wang

Huang

, et al. Magnetron sputtering nichrome on fiber fabric to construct microwave-absorbing structure. Appl Phys a-Materials Sci Process 2020; 126(11): 863.

29.

Melvin

GJH

Q-Q

Suzuki

, et al. Microwave-absorbing properties of silver nanoparticle/carbon nanotube hybrid nanocompositesnanocomposites. J Mater Sci 2014; 49(14): 5199–5207.

30.

Tang

Wang

D-J

, et al. Lightweight nonwovennonwoven fabric graphene aerogel composite matrices for assembling carbonyl iron as flexible microwave absorbing textiles. J Mater Science-Materials Electronics 2019; 30(18): 17137–17144.

31.

Zou

Jiang

Shu

, et al. Enhancing and tuning absorption properties of microwave absorbing materials using metamaterials. Appl Phys Lett 2008; 93(26): 261115.

32.

Zhou

Sun

, et al. Microwave absorbing properties of Fe3O4-poly (3, 4-ethylene dioxythiophene) hybrids in low-frequency band. Polym Adv Tech 2014; 25(1): 83–88.

33.

Liu

Huang

Z-B

Luo

, et al. Dielectric and microwave-absorbing properties of the carbon/alumina/silica coating. J Inorg Mater 2012; 27(8): 817–821.

34.

Duan

Wang

Liu

, et al. Microwave properties of double layer absorber reinforced with carbon fibre powders. Plastics Rubber and Composites 2013; 42(2): 82–87.

35.

Folgueras

Rezende

. Multilayer radar absorbing material processing by using polymeric nonwoven and conducting polymer. Mater Research-Ibero-American J Mater 2008; 11(3): 245–249.

36.

Schurig

Mock

Justice

, et al. Metamaterial electromagnetic cloak at microwave frequencies. Science 2006; 314(5801): 977–980.

37.

Tan

, et al. Electromagnetic and microwave-absorbing properties of co-based amorphous wire and Ce2Fe17N3-delta composite. J Alloys Compounds 2018; 730: 255–260.

38.

Zheng

Qin

Wang

, et al. microwave absorbing properties of composites containing ultra-low loading of optimized microwires. Composites Sci Technology 2017; 151: 62–70.

39.

Breiss

El Assal

Harmouch

, et al. Ultra-porous and lightweight microwave absorber based on epoxy foam loaded with long carbon fibers. Mater Res Bull 2021; 137: 111188.

40.

Ding

Zhang

Luo

, et al. Investigation on the broadband electromagnetic wave absorption properties and mechanism of Co3O4-nanosheets/reduced-graphene-oxide composite. Nano Res 2017; 10(3): 980–990.

41.

Gao

Zhu

Xia

, et al. Direct preparation of al-base alloys from their oxides/metal precursors in the eutectic LiCl-KCl melt. J Alloys Compounds 2016; 665: 124–130.

42.

Sun

, et al. Laminated magnetic graphene with enhanced electromagnetic wave absorption properties. J Mater Chem C 2013; 1(4): 765–777.

43.

Chen

Shen

, et al. Design of phase matching chessboard-like electromagnetic metasurfaces for wideband radar cross section reduction. Microwave Opt Technology Lett 2019; 61(9): 2037–2045.

44.

Shen

Hou

Zhang

, et al. Recent progress in SiC nanowires as electromagnetic microwaves absorbing materials. J Alloys Compounds 2020; 815: 152388.

45.

Peng

Zhang

Xie

, et al. Fabrication of core-shell nanoporous carbon@chiral polyschiff base iron(II) composites for high-performance electromagnetic wave attenuation in the low-frequency. J Alloys Compounds 2021; 850: 156816.

46.

Yuan

, et al. Enhanced magnetic permeability and electromagnetic noise suppression by sieved and oriented large flaky sendust particles. J Magnetism Magn Mater 2022: 543: 168650.

47.

Jia

Lan

Lin

, et al. Progress in low-frequency microwave absorbing materials. J Mater Science-Materials Electronics 2018; 29(20): 17122–17136.

48.

Wang

Liu

Jiao

, et al. Hierarchical carbon fiber@MXene@MoS(2) core-sheath synergistic microstructure for tunable and efficient microwave absorption. Adv Funct Mater 2020; 30(45): 2002595.

49.

Han

. Preparation and performance of wave absorbing materials by metallization of nocadia. Acta Chim Sinica 2011; 69(1): 53–58.

50.

Wang

Zhang

, et al. Ultra-wide-band microwave composite absorbers based on phase gradient metasurfaces. Prog In Electromagnetics Res M 2014; 40: 9–18.

51.

Jia

Wang

Zhu

, et al. Synthesis of lightweight and flexible composite aerogel of mesoporous iron oxide threaded by carbon nanotubes for microwave absorption. J Alloys Compounds 2017; 697: 138–146.

52.

Shagor

RMR

Abedin

Asmatulu

. Mechanical and thermal properties of carbon fiber reinforced composite with silanized graphene as nano-inclusions. J Compos Mater 2021; 55(5): 597–608.

53.

Cheng

Zhang

Zhan

, et al. Preparation and properties of ni-w composite coatings reinforced by graphene nanoplatelets. Adv Eng Mater 2021; 23(8): 2001309.

54.

Cao

Wang

X-X

Yuan

, et al. Temperature dependent microwave absorption of ultrathin graphene composites. J Mater Chem C 2015; 3(38): 10017–10022.

55.

Rubrice

Castel

Himdi

, et al. Dielectric characteristics and microwave absorption of graphene composite materials. Materials 2016; 9(10): 825.

56.

Jin

. Nitrogen-doped graphene: synthesis, characterizations and energy applications. J Energy Chem 2018; 27(1): 146–160.

57.

Mohamadi

Ramakrishna

Chinnappan

, et al. Highly-efficient microwave absorptivity in reduced graphene oxide modified with PTA@ imidazolium-based dicationic ionic liquid and fluorine atom. Composites Sci Technology 2020; 188: 107960.

58.

Ullah

Yang

, et al. Graphene transfer methods: a review. Nano Res 2021; 14(11): 3756–3772.

59.

Duan

O’Donnell

Sun

, et al. Sulfur and nitrogen co-doped graphene for metal-free catalytic oxidation reactions. Small 2015; 11(25): 3036–3044.

60.

Iamprasertkun

Krittayavathananon

Sawangphruk

. N-doped reduced graphene oxide aerogel coated on carboxyl-modified carbon fiber paper for high-performance ionic-liquid supercapacitors. Carbon 2016; 102: 455–461.

61.

Van Tam

Kang

Babu

, et al. Synthesis of B-doped graphene quantum dots as a metal-free electrocatalyst for the oxygen reduction reaction. J Mater Chem A 2017; 5(21): 10537–10543.

62.

Wang

Han

X-J

, et al. The electromagnetic property of chemically reduced graphene oxide and its application as microwave absorbing material. Appl Phys Lett 2011; 98(7): 072906.

63.

Min

Zhou

Yuchang

, et al. Single-layer and double-layer microwave absorbers based on graphene nanosheets/epoxy resin composite. Nano 2017; 12(7): 046101.

64.

Sun

Yan

Yue

, et al. Novel high-performance electromagnetic absorber based on nitrogen/boron co-doped reduced graphene oxide. Composites Part B-Engineering, 2020; 196: 108132.

65.

Chu

. Enhanced visible-light-driven photocatalytic activity of F doped reduced graphene oxide - Bi2WO6 photocatalyst. Appl Organomet Chem 2019; 33(1): e4682.

66.

Shin

Kim

Jun

, et al. Highly selective FET-type glucose sensor based on shape-controlled palladium nanoflower-decorated graphene. Sensors and Actuators B-Chemical 2018; 264: 216–223.

67.

Sprinkle

Siegel

, et al. First direct observation of a nearly ideal graphene band structure. Phys Rev Lett 2009; 103(22): 226803.

68.

Novoselov

Geim

Morozov

, et al. Electric field effect in atomically thin carbon films. Science 2004; 306(5696): 666–669.

69.

Wang

Zhu

, et al. CoFe2O4/N-doped reduced graphene oxide aerogels for high-performance microwave absorption. Chem Eng J 2020; 388: 124317.

70.

Quan

Qin

Estevez

, et al. Magnetic graphene for microwave absorbing application: Towards the lightest graphene-based absorber. Carbon 2017; 125: 630–639.

71.

Zhou

Wang

Muhammad

, et al. Graphene nanoflakes with optimized nitrogen doping fabricated by are discharge as highly efficient absorbers toward microwave absorption. Carbon 2019; 148: 204–213.

72.

Chamoli

Singh

Akhtar

, et al. Nitrogen-doped graphene nanosheet-epoxy nanocompositenanocomposite for excellent microwave absorption. Physica E-Low-Dimensional Syst Nanostructures 2018; 103: 25–34.

73.

Sultanov

Daulbayev

Bakbolat

, et al. Advances of 3D graphene and its composites in the field of microwave absorption. Adv Colloid Interf Sci 2020; 285: 102281.

74.

Pramoda

Kumar

Rao

CNR

. Graphene/single-walled carbon nanotube composites generated by covalent cross-linking. Chemistry-an Asian J 2015; 10(10): 2147–2152.

75.

Ahmad

Soren

Dey

, et al. Synergistic reinforcement effect of 3D graphene@multi-walled carbon nanotube hybrid nanofiller in enhancing the electrical, EMI-shielding, and mechanical properties of polyethersulfone. Int J Polym Anal Characterization 2021; 26(8): 754–771.

76.

Chen

Huang

, et al. Synergistically assembled MWCNT/graphene foam with highly efficient microwave absorption in both C and X bands. Carbon 2017; 124: 506–514.

77.

Shu

Wan

Zhang

, et al. Facile design of three-dimensional nitrogen-doped reduced graphene oxide/multi-walled carbon nanotube composite foams as lightweight and highly efficient microwave absorbers. Acs Appl Mater Inter 2020; 12(4): 4689–4698.

78.

Zhang

Huang

Chen

, et al. Composition and structure control of ultralight graphene foam for high-performance microwave absorption. Carbon 2016; 105: 438–447.

79.

Culchac

Del Grande

Capaz

, et al. Flat bands and gaps in twisted double bilayer graphene. Nanoscale 2020; 12(8): 5014–5020.

80.

Nimbalkar

Kim

. Opportunities and challenges in twisted bilayer graphene: a review. Nano-Micro Lett 2020; 12(1): 126.

81.

Zhang

. Lowest-energy moire band formed by Dirac zero modes in twisted bilayer graphene. Sci Bull 2019; 64(8): 495–498.

82.

Haddadi

Kruchkov

, et al. Moire flat bands in twisted double bilayer graphene. Nano Lett 2020; 20(4): 2410–2415.

83.

Ren

Wang

, et al. Current progress on the modification of carbon nanotubes and their application in electromagnetic wave absorption. Rsc Adv 2014; 4(28): 14419–14431.

84.

Wang

Jianguo

Qiaoxin

, et al. Microwave permeability change of FeCo nanocrystalline during high energy ball milling. J Wuhan Univ Technology-Materials Sci Edition 2006; 21(1): 16–18.

85.

Shan

, et al. Low-frequency perfect sandwich meta-absorber based on magnetic metal. Mod Phys Lett B 2019; 33(6): 1950057.

86.

Chen

Huang

, et al. Graphene-based materials toward microwave and terahertz absorbing stealth technologies. Adv Opt Mater 2019; 7(8): 1801318.

87.

Wang

Zang

Jiao

. Magnetic ferrite/conductive polyaniline nanocompositenanocomposite as electromagnetic microwave absorbing materials in the low frequency. In 2nd international conference on measurement, instrumentation and automation, ICMIA 2013. Guilin, China, 23–24 April 2013.

88.

Kershi

. Spectroscopic, elastic, magnetic and optical studies of nanocrystallite and nanoferro-fluids co ferrites towards optoelectronic applications. Mater Chem Phys 2020; 248: 122941.

89.

Yin

Zhang

Jiang

, et al. Recycling of waste straw in sorghum for preparation of biochar/(Fe,Ni) hybrid aimed at significant electromagnetic absorbing of low-frequency band. J Mater Res Technology-Jmr&T 2020; 9(6): 14212–14222.

90.

Yang

, et al. Synthesis of reduced graphene oxide/zinc ferrite/nickel nanohybrids: as a lightweight and high-performance microwave absorber in the low frequency. J Mater Science-Materials Electronics 2019; 30(20): 18496–18505.

91.

Mederos-Henry

Mahin

Pichon

, et al. Highly efficient wideband microwave absorbers based on zero-valent fe@gamma-fe2o3 and fe/co/ni carbon-protected alloy nanoparticles supported on reduced graphene oxide. Nanomaterials 2019; 9(9): 1196.

92.

Sun

Liao

, et al. Enhanced microwave absorption performance of highly dispersed CoNi nanostructures arrayed on graphene. Nano Res 2018; 11(5): 2689–2704.

93.

Wang

Jiao

Shi

, et al. Synthesis of porous nitrogen-doped graphene decorated by gamma-Fe2O3 nanorings for enhancing microwave absorbing performance. Ceramics Int 2020; 46(1): 1002–1010.

94.

Guo

Q-D

Xiao

Z-Y

, et al. performance enhanced electromagnetic wave absorber from controllable modification of natural plant fiber. Rsc Adv 2019; 9(29): 16690–16700.

95.

Liu

Xie

Sun

, et al. Micro-scale modeling of textile composites based on the virtual fiber embedded models. Composite Structures, 2019; 230: 111552.

96.

Liu

Zhang

Xiao

, et al. Preparation and properties of cobalt oxides coated carbon fibers as microwave-absorbing materials. Appl Surf Sci 2011; 257(17): 7678–7683.

97.

Yamamoto

Egami

Nishida

, et al. Microwave absorbing property of stacked polypyrrole-coated nonwoven textiles. Jpn J Appl Phys 2011; 50(9): 09NF04.

98.

Zheng

. Study on General Geometrical Modeling of Single Yarn with 3D Twist Effect. Textile Res J 2010; 80(10): 867–879.

99.

Ozen

Sancak

Beyit

, et al. Investigation of electromagnetic shielding properties of needle-punched nonwoven fabrics with stainless steel and polyester fiber. Textile Res J 2013; 83(8): 849–858.

100.

Ozkan

Telli

. The effects of metal type, number of layers, and hybrid yarn placement on the absorption and reflection properties in electromagnetic shielding of woven fabrics. J Engineered Fibers Fabrics 2019; 14: 1558925019860961.

101.

. Effects of three-dimensional reduced graphene oxide coupled with nickel nanoparticles on the microwave absorption of carbon fiber-based composites. J Alloys Compounds 2017; 717: 205–213.

A review of graphene-based broad bandwidth microwave absorbing textile-based composites in the low-frequency range

Abstract

Keywords

Introduction

The absorbing mechanism of the Microwave Absorbing Materials (MWAMs)

Graphene-based absorbers (GBAs) with dielectric loss

Modification of the molecular structure of G.N

Modification of the morphology structure of G.N

Modification of the supramolecular structure of G.N.

The hybrid of GBAs/MLAs functional particles in the low-frequency range

The GBM/MLA-added textile-based composites

Conclusions and perspectives

Footnotes

Declaration of conflicting interests

Funding

ORCID iD

Nomenclatures

References