Excellent Electromagnetic Wave Absorption Performance Research Articles

Graphene Aerogel Composites with Self-Organized Nanowires-Packed Honeycomb Structure for Highly Efficient Electromagnetic Wave Absorption

HighlightsA new strategy for elaborate regulation of microstructure was successfully introduced by the ice template‑assisted 3D printing and chemical vapor deposition strategy, including graphene nanoplate/silicon carbide nanowires hierarchical porous structure and graphene nanoplate/boron nitride composite heterogeneous interface.The composite exhibits excellent electromagnetic wave absorption performance with an RLmin of -37.8 dB and an EABmax of 9.2 GHz (from 8.8 to 18.0 GHz) at 2.5 mm. And the high-temperature absorption stability makes it a promising absorber candidate under high temperature and oxidizing atmosphere.

Improved Interfacial Interactions by Core-Shell CoFe2O4@SiO2 Composites to Enhance the Ability of Corrosion Resistance and Electromagnetic Wave Absorption.

With the rapid development of science and technology, stealth and anti-corrosion activities in oceans have attracted widespread attention. This study successfully prepares CoFe2O4@SiO2 with a core-shell structure. This core-shell structure endows the CoFe2O4@SiO2 with good impedance matching and interfacial polarization. Thus, the CoFe2O4@SiO2 exhibits an excellent electromagnetic wave absorption performance with a minimum reflection loss of -45.16dB. Moreover, the CoFe2O4@SiO2 exhibits an excellent dispersion ability in epoxy. The corrosion resistance of the CoFe2O4@SiO2/epoxy is enhanced. After 60 days of immersion, the low-frequency impedance modulus of the CoFe2O4@SiO2/epoxy is still >109Ωcm2. The CoFe2O4@SiO2 realize the dual functions of stealth and anti-corrosion, which provide ideas for developing marine stealth applications.

Upcycling Spent Graphite from Li-ion Batteries into Cu/Expanded Graphite Composites as high-performance electromagnetic wave absorbers.

With the widespread adoption of lithium-ion batteries and modern electronic components in both daily life and industrial production, there is a growing focus on the high-value recycling of spent lithium-ion batteries and the development of absorbents with high electromagnetic wave absorption capabilities. Efficiently regenerating recycling graphite from spent batteries through low-cost methods and utilizing it to prepare high-performance electromagnetic wave absorbing materials holds significant importance in addressing both the utilization of waste graphite and electromagnetic pollution issues simultaneously. This work presents a method to transform spent graphite into expanded graphite with a three-dimensional conductive structure using an enhanced Hummer's treatment and thermal reduction process. Subsequently, Cu/EG composite materials were efficiently prepared through straightforward mechanical ball milling and calcination. The unique honeycomb-like porous structure of expanded graphite facilitates the reflection and scattering of electromagnetic waves, electron transfer, and defect polarization. Additionally, the incorporation of copper nanoparticles improves the conduction loss and enhances interface polarization, allowing for precise tuning of the composite material's absorption performance. The results demonstrate that Cu/EG composite materials exhibit excellent electromagnetic wave absorption performance. The Cu/EG(1:3) sample exhibits effective absorption in the C, X, and Ku bands, achieving a minimum reflection loss (RLmin) of -54 dB and a maximum effective absorption bandwidth (EABmax) of 5.28 GHz. This performance is attained with a thickness of just 2.2 mm and a filler content of only 15 wt.%.

Preparation of broad-bandwidth porous carbon electromagnetic wave absorption materials from agricultural waste corncob

Developing advanced electromagnetic wave-absorbing materials tend to focus on the characteristics of low cost, renewability, environmental friendliness, strong absorption, wide bandwidth, and lightweight. This paper described the preparation of porous carbon electromagnetic wave-absorbing materials with strong absorption, broad bandwidth and thin thickness by one-step charring of corncob, an agricultural waste. The corncob porous carbon (CPC) materials were prepared when the charring temperature was 600 °C, the charring time was 3 h and the activator ratio was 0.25:1. The obtained CPC exhibited porous microstructure with average pore size of approximately 1 μm. Its specific surface area was 713.971 m2·g−1, with pore volume of 0.289 mL·g−1 and high degree graphitization. CPC showed excellent electromagnetic wave absorption performance with minimum reflection loss (RL min) of −38.21 dB and effective absorption bandwidth (EAB) of 5.6 GHz at a relatively thin thickness of 2.0 mm. CPC was capable of absorbing 99.9 % of electromagnetic wave (EMW).

Microwave absorption properties of one-step formed CNTs/Fe3O4-carbonyl iron superflexible buckypaper by directional pressure filtration

In order to realize the integration of structure and function of microwave-absorbing materials, carbon nanotubes/magnetic nanoparticle buckypaper (CNT/MNP BP) self-supporting, ultra-flexible, ultra-thin and ultra-light composites were prepared by composing CNTs with MNPs through directional pressure filtration technology. The BP composite, with a bulk density of 0.62 g/cm3 and a thickness of 0.21 mm, can be uninterruptedly tightly wound around a 4 mm diameter glass rod many times without structural damage. The microwave-absorbing properties and magnetic properties of the CNT/MNP composites with different compositions and contents were systematically analyzed. The CNT-Fe3O4 Buckypaper with 33.3 wt% Fe3O4 content (CF33.3 %) has the best electromagnetic wave absorption capability, with a minimum reflection loss value of −52.01 dB and an effective absorption bandwidth of 4.08 GHz. The VSM test shows that the saturation magnetization strength of CF33.3 % is 38.4 emu/g. The excellent electromagnetic wave absorption performance is attributed to the polarization and conduction losses of CNTs, natural resonance, exchange resonance and eddy current losses of MNPs, and multiple scattering and reflection within the porous network structure of the composites. The CNTs and MNPs has good dispersion in the buckypaper, where CNTs construct a superflexible skeleton besides an excellent conductive network. The self-supporting superflexible CNT/MNP BP composites have a good application prospect in the field of wearable electronic devices in the future.

One-step fabrication of a novel fiber-based absorber for flexible, tunable and boosted microwave absorption

The increasingly intricate electromagnetic environment necessitates higher anti-electromagnetic interference capabilities for electronic devices, thereby demanding a flexible absorbing material that can adapt to multiple forms, is lightweight, and exhibits excellent electromagnetic wave (EMW) absorption properties. In this study, we have developed a novel flexible absorbing material (FAM) based on glass-coated amorphous magnetic fibers (SFs) and Dallenbach-like absorbing structures through wet forming technology. By combining high-performance absorbing fiber with textile structures, the FAM demonstrates EMW absorption performance along with lightweight flexibility and shape adaptability. This paper explores the influence of process parameters in wet forming technology on FAM formation; as well as examines the construction of broadband absorbers through structural optimization. A single-layer FAM with a thickness of 1.7 mm (SFs length 8 mm, content 3 g/m2) achieves an impressive reflection loss (RL) value of −60.1 dB at 11.6 GHz. Furthermore, optimized multi-layer FAM attains effective absorption bandwidth (EAB: RL ≤ −5 dB) across a wide range from 3–14 GHz. This work presents a new approach for developing ’lightweight, thin, wide, and strong’ absorbing materials based on fiber and textile structures which holds significant implications for civilian electromagnetic interference protection as well as military electromagnetic stealth technology.

Synergistically magnetic and dielectric properties of two dimensional Fe3Al@PPy lamellae exhibiting broadband and strong electromagnetic wave absorption

Addressing the issue of low impedance characteristics is essential to improve the electromagnetic wave absorption performance of magnetic materials. Herein, two dimensional Fe3Al@polypyrrole (PPy) lamellae with synergistic magnetic and dielectric properties are fabricated by a mechanical alloying, ordering transformation and polymerization process, which exhibits excellent electromagnetic wave absorption performance. By carefully controlling the thickness of the PPy shell, the optimized Fe3Al@PPy lamellae show a minimum reflection loss of −45.6 dB and an effective absorption bandwidth of 9.1 GHz at a thickness of only 1.5 mm. The conformal growth of Fe3Al@PPy lamellae can induce strong interfacial polarization, dipole polarization, multiple scattering effect and magnetic loss behaviors for the attenuation of electromagnetic waves. This study demonstrates a facile strategy for the development of efficient Fe3Al@PPy composite absorbents showing great potential for practical applications.

Regulation of PPy Growth States by Employing Porous Organic Polymers to Obtain Excellent Microwave Absorption Performance.

Regulating the different growth states of polypyrrole (PPy) is a key strategy for obtaining PPy composites with high electromagnetic wave (EMW) absorption properties. This work finds that the growth states of PPy is regulated by controlling the amount of pyrrole added during the preparation of composites, so as to regulate the development of conductive networks to obtain excellent EMW absorption performance. The POP/PPy-200 composite achieves an effective absorption bandwidth (EAB) of 6.24GHz (11.76-18.00GHz) at a thickness of only 2.34mm, covering 100% of the Ku band. The minimum reflection loss of -73.05dB can be demonstrated at a thickness of only 2.29mm, while at the same time showing an EAB of 5.96GHz to meet the requirements of "thin", "light", "wide", and "strong". Such excellent EMW absorption performance is attributed to the conductive loss caused by the regulation of the growth states of PPy and the polarization loss caused by the heterostructure. This work also addresses the key challenge that porous organic polymers (POPs) cannot be applied to EMW absorption due to poor conductivity and providing new insights into the candidates for EMW absorbing materials.

A clean bamboo-based carbon-iron multi-interface complex for electromagnetic radiation attenuation and thermal insulation

Civilian electromagnetic wave (EMW) absorbers are urgently needed to solve the excessive electromagnetic (EM) radiation energy pollution. Biomass, such as wood and bamboo, has a wide range of sources, is porous, and is suitable for forming functional composites. However, the diverse composition and microstructure directly affect the EM and thermal properties of conversion composites, and the corresponding influencing mechanisms are unclear. Here, a series of iron-containing biochar-based composites (CFBs) were synthesized by in-situ pyrolysis of impregnated flattened bamboo sliced veneers with Fe(acac)3 dimethylformamide (DMF) solutions. The components and microstructures were pre-regulated through moisture-heat coupling softening, flattening and slicing treatments. Excellent EMW absorption performance with a |RLmin| value as large as 33.03 dB was obtained for CFB-0.8 at a fixed thickness of 1.15 mm, along with the widest effective frequency bandwidth as large as 4.08 GHz. Besides, In addition, CFB-0.8 has stable Joule heating performance (0.9V, 79.7 °C), and its in-plane thermal conductivity is 31.4 times that of flattened bamboo (0.62 W m−1 K−1). These are attributed to the rich heterojunction interfaces, electromagnetic attenuation caused by structures (porous structure scattering, nanoscale effects), deep absorption mechanisms caused by defects (lattice defects, electric field concentration, non-uniform carbonization structures), and thermal conversion. This work provides theoretical and experimental data for developing EMW absorption materials and new ideas for the high-value utilization of biomass materials and the continuation of their carbon fixation life.

Exploring Broadband Electromagnetic Absorption Characteristics and Composition Optimization in Novel Synthesized Ni2Fe1+xGe1−x Alloy Powders

This study reports for the first time the successful synthesis of a novel series of Ni2Fe1+xGe1−x (x = 0.25, 0.50, 0.75, 0.90) polycrystalline alloy materials with L21 austenite structure using the mechanical alloying method. Notably, the Ni2Fe1+xGe1−x alloys demonstrate excellent electromagnetic wave absorption performance across the entire 2–18 GHz frequency range, and by adjusting the composition ratio of iron and germanium, it is possible to effectively regulate their complex permittivity () and permeability (), thereby adjusting the reflection loss. All Ni2Fe1+xGe1−x samples show an effective electromagnetic wave absorption effect of more than −10 dB, indicating that 90% of the electromagnetic waves are efficiently absorbed. Among them, the Ni2Fe1.5Ge0.5 sample achieves an outstanding −43.5 dB reflection loss at 3.2 GHz, and the maximum effective absorption bandwidth reaches 5.8 GHz (11.8–17.6 GHz) with just a 1.6 mm thickness, fully covering the Ku band. This excellent absorption ability comes from the strong ability of the material to reduce signal strength and its perfect impedance matching. This study first shows the high potential of Ni2Fe1+xGe1−x ferromagnetic alloys as effective, wide‐range electromagnetic wave absorbers. It suggests the ferromagnetic Ni2Fe1+xGe1−x alloys hold promise as appealing candidates for broadband and high‐efficiency electromagnetic wave absorption.

Ultralight and rigid PBO nanofiber aerogel with superior electromagnetic wave absorption properties

Polymer-based aerogels are emerging as promising candidates for lightweight and high performance electromagnetic (EM) wave absorption materials. In this study, an ultralight and rigid poly(p-phenylene benzobisoxazole) nanofiber (PNF) based composite aerogel with excellent EM wave absorption performance was fabricated with cobalt-nickel alloy (CoNi) nanoparticles and carbon nanotubes (CNTs) as magnetic and conductive fillers, respectively. A CNT/PNF composite aerogel was first prepared through a sol-gel and freeze-drying method, and then CoNi nanoparticles were introduced therein through hydrothermal reaction and thermal annealing to obtain the CoNi/CNT/PNF aerogel. CNTs and PNFs were interwoven and constructed a three-dimensional conductive/magnetic cage-like skeleton structure decorating with magnetic CoNi nanoparticles. The cage-like skeleton structure allowed the dissipation of EM waves through multiple mechanisms encompassing conduction loss, magnetic loss, multiple reflection, scattering, and absorption. When its thickness was 4 mm, the CoNi/CNT/PNF aerogel showed a minimal reflection loss of −44.7 dB (at 6.88 GHz), and its broad effective absorption bandwidth covered the entire X-band and Ku-band and most of the C-band (12.32 GHz, from 5.68 GHz to 18 GHz). In addition, the rigid aerogel exhibited an ultralow density (0.107 g/cm3), excellent thermal insulation, and flame retardancy, demonstrating its potential application as a high-performance EM wave absorption material in the fields of aerospace and national defense.

Kirkendall Effect-Induced Ternary Heterointerfaces Engineering for High Polarization Loss MOF-LDH-MXene Absorbers.

Heterogeneous interfacial engineering has garnered widespread attention for optimizing polarization loss and enhancing the performance of electromagnetic wave absorption. A novel Kirkendall effect-assisted electrostatic self-assembly method is employed to construct a metal-organic framework (MOF, MIL-88A) decorated with Ni-Fe layered double hydroxide (LDH), forming a multilayer nano-cage coated with Ti3C2Tx. By modulating the surface adsorption of Ti3C2Tx on LDH, the heterointerfaces in MOF-LDH-MXene ternary composites exhibit excellent interfacial polarization loss. Additionally, the Ni-Fe LDH@Ti3C2Tx nano-cage exhibits a large specific surface area, abundant defects, and a large number of heterojunction structures, resulting in excellent electromagnetic wave absorption performance. The MIL-88A@Ni-Fe LDH@Ti3C2Tx-1.0 nano-cage achieves a reflection loss value of -46.7 dB at a thickness of 1.4mm and an effective absorption bandwidth of 5.12 GHz at a thickness of 1.8mm. The heterojunction interface composed of Ni-Fe LDH and Ti3C2Tx helps to enhance polarization loss. Additionally, Ti3C2Tx forms a conductive network on the surface, while the cavity between the MIL-88A core and the Ni-Fe LDH shell facilitates multiple attenuations by increasing the transmission path of internal incident waves. This work may reveal a new structural design of multi-component composites by heterointerfaces engineering for electromagnetic wave absorption.

Lightweight and hierarchical carboxyl chitosan-derived carbon aerogel for electromagnetic wave absorber and heat insulation

In recent years, carbon aerogels derived from biomass have shown promising potential in electromagnetic wave (EMW) absorption field owing to their lightweight nature, controllable structure, environmental friendliness, and abundant pore structure. This study reports a novel type of carbon aerogels based on carboxyl chitosan (CCS) and graphene oxide (GO) with rich pores and a unique three-dimensional interconnected structure through solution mixing, freeze-drying, and pyrolysis process. The EMW absorption performances of the carboxyl chitosan/GO xerogel derived carbon aerogels (CGCAs) are adjusted by varying the content of graphene oxide (GO). The nitrogen elements inherent in chitosan can provide a large number of defects to the carbonized material, effectively capturing and attenuating EMW. Synthesized CGCAs show excellent EMW absorption performance with increasing GO content and the CGCA-6 exhibits the best performance. At a thickness of 1.7 mm, it has RLmin of −61.67 dB, and at a thickness of 1.5 mm, it has the widest effective absorption bandwidth (EAB) of 4.24 GHz (12.96–17.12 GHz). Additionally, under far-field conditions, at a thickness of 1.7 mm, the maximum radar cross-section (RCS) reduction relative to a PEC plate for the prepared CGCA-6 is 22.28 dB m2. Furthermore, the good thermal insulation capability exhibited by CGCA-6 makes it suitable for complex application scenarios. Therefore, this biomass-derived multi-functional carbon aerogel with excellent EMW absorption performance, radar stealth, infrared stealth, and thermal insulation capabilities has broad prospects for applications in EMW protection and aerospace fields.

Synergistic microwave absorption effect of graphene-BN-Fe3O4 composite at thin thickness

With the quick evolution of information technology, it is necessary to develop high-performance microwave absorbers to attenuate electromagnetic waves. Herein, we prepared graphene-BN-Fe3O4 composites by a facile solvothermal method using graphene as the dielectric loss component, Fe3O4 as the magnetic loss component and BN as the dielectric modulating component. BN and graphene form a 2D/2D structure adhered with Fe3O4. When the ratio of BN to graphene is 1:1 with Fe3O4 content of 60 %, the absorber exhibits excellent electromagnetic wave absorption performance. A RLmin of −42.31 dB is obtained with an effective band of 4.5 GHz at 1.04 mm, while the maximum EAB of samples can reach 4.59 GHz (13.41–18 GHz) with a RLmin value of –33.16 dB at 1.05 mm. The prepared composite exhibits a wide absorption band at a thin thickness. Enhanced microwave absorption performance is achieved mainly due to the synergistic effect of increased interface polarization loss, appropriate conductive loss, and improved impedance matching.

Multi-component attached carbon matrix composites with superior electromagnetic wave absorption performance and multifunctional applications

The preparation of highly absorbing and high-performance electromagnetic wave-absorbing materials remains a significant challenge. In this paper, carbon matrix composites modified with sodium inorganic salts (CMS) have been successfully prepared by using the solvent evaporation method in combination with the hydrothermal treatment and high temperature carbonization processes. The composition of the product can be manipulated by varying the material ratios, which in turn affects the interface and dielectric properties of the material. Sodium carbonate (Na2CO3) was produced as a transition phase between sodium silicate and carbon matrix due to high temperature. According to differential charge density a significant charge accumulation found between the interfacial of Na2CO3 and carbon layer is helpful to polarization. The synergistic effect of polarization and conduction loss due to the formation of multiple heterogeneous interfaces and carbon matrix results in excellent electromagnetic wave absorption performance. The minimum reflection loss (RLmin) is −55.49 dB when the thickness is 3.1 mm. Furthermore, CMS composites exhibit notable flame retardancy and thermal insulation properties, rendering them suitable for a diverse range of applications. These remarkable achievements provide new ideas for the design and development of efficient electromagnetic wave absorption materials.

Synthesis of Mo2C/C nanoclusters attached on rGO nanosheets for high-Efficiency electromagnetic wave absorption

It is an effective strategy that constructing composites with a multi-dimensional structure synergistically enhance their electromagnetic (EM) wave absorbing performance. Herein, a high-efficiency EM wave absorber of Mo2C/C nanoclusters uniformly encapsulated in rGO nanosheets (Mo2C/C-rGO) was prepared by a combination of the directing freeze-dry and subsequently carbothermal reaction method. Mo2C/C was in-situ induced from spherical phosphomolybdic acid/polypyrrole (PMo12/PPy) to result in a unique cluster-like microstructure. Abundant heterogeneous interfaces endowed the Mo2C/C-rGO composites with excellent EM wave absorption performance at a low filling ratio of 5 wt%. The minimum reflection loss (RL) value was −49.3 dB at 1.38 mm and the maximum effective absorption bandwidth (EAB, RL<-10 dB) was 5.12 GHz at 1.60 mm. The excellent performance was owing to the lamellar structure and abundant heterogeneous interfaces in Mo2C/C-rGO, lengthening the transmission path of the incident wave, as well as resulting in high conduction loss and interfacial polarization loss. This universal strategy would be extended to other absorbers with multi-interface structures for lightweight and broadband EM wave absorption.

High-performance electromagnetic wave absorption in VS2@multi-walled carbon nanotube composites

In this work, composites comprising VS2 and multi-walled carbon nanotubes (MWCNTs) were prepared using a simple hydrothermal method. The MWCNTs were dispersed among the VS2 nanosheets, which produced dipole polarization and interfacial polarization, thus enhancing the dielectric loss. Meanwhile, the electrical conductivity of the composites gradually increased with the rising content of the MWCNTs, which improved the electromagnetic wave absorption performance. By adjusting the mass ratio of VS2 to MWCNTs to 5:1, a minimum reflection loss value (RL) of −24.7 dB was achieved with a thickness of only 1.3 mm at a frequency of 14.4 GHz. Besides, when the thickness was reduced to 1.2 mm, the effective absorption bandwidth extended to 3.75 GHz. The results suggest that impedance matching and the synergistic effect of multiple loss mechanisms contribute to the excellent electromagnetic wave absorption performance of the materials. Consequently, the VS2/MWCNTs composites exhibit simple synthesis, wide absorption bandwidth, thin thickness, and high absorption capacity, rendering them a promising material for practical microwave absorption applications.

Microstructure evolution and excellent electromagnetic wave absorption performance of SiBCN fibers

In this work, SiBCN fibers with excellent electromagnetic wave (EMW) absorption performance were fabricated using electrospinning technology, followed by curing, pyrolysis, and heat treatment. Microstructure evolution and EMW absorption performance of SiBCN fibers after heat treatment at 1200–1600 °C were investigated. After heat treatment at 1200 °C, the conductive turbostratic C was precipitated from amorphous SiBCN fibers, resulting in minimum reflection loss (RLmin) reaching −63 dB and efficient absorption bandwidth (EAB) reaching 5.2 GHz. While turbostratic C and nano-SiC grains were simultaneously precipitated from SiBCN fibers heat treated at 1400 °C, and the RLmin reached −67 dB. The excellent EMW absorption performance of SiBCN fibers was mainly attributed to the synergistic effect of conductive loss, dipole polarization, and interfacial polarization. This work can guide the fabrication of high-performance EMW-absorbing ceramic fibers.

In Situ Exsolution-Prepared Solid-Solution-Type Sulfides with Intracrystal Polarization for Efficient and Selective Absorption of Low-Frequency Electromagnetic Wave.

The excellent dielectric properties and tunable structural design of metal sulfides have attracted considerable interest in realizing electromagnetic wave (EMW) absorption. However, compared with traditional monometallic and bimetallic sulfides that are extensively studied, the unique physical characteristics of solid-solution-type sulfides in response to EMW have not been revealed yet. Herein, a unique method for preparing high-purity solid-solution-type sulfides is proposed based on solid-phase in situ exsolution of different metal ions from hybrid precursors. Utilizing CoAl-LDH/MIL-88A composite as a precursor, Fe0.8Co0.2S single-phase nanoparticles are uniformly in situ formed on an amorphous substrate (denoted as CoAl), forming CoAl/Fe0.8Co0.2S heterostructure. Combing with density functional theory (DFT) calculations and wave absorption simulations, it is revealed that Fe0.8Co0.2S solid solution has stronger intracrystal polarization and electronic conductivity than traditional monometallic and bimetallic sulfides, which lead to higher dielectric properties in EM field. Therefore, CoAl/Fe0.8Co0.2S heterostructure exhibits significantly enhanced EMW absorption ability in the low-frequency region (2-6GHz) and can achieve frequency screening by selectively absorbing EMW of specific frequency. This work not only provides a unique method for preparing high-purity solid-solution-type sulfides but also fundamentally reveals the physical essence of their excellent EMW absorption performance.

Preparation of nitrogen-doped reduced graphene oxide/zinc ferrite@nitrogen-doped carbon composite for broadband and highly efficient electromagnetic wave absorption

Traditionally reduced graphene oxide (RGO)-based electromagnetic wave (EMW) absorbing materials have poor absorption effectiveness due to impedance mismatch caused by skin effect. The introduction of structural defects and the design of heterogeneous interfaces play a crucial role in enhancing the polarization effect of EMW absorbers. In this study, nitrogen-doped reduced graphene oxide/zinc ferrite@nitrogen-doped carbon (NRGO/ZnFe2O4@NC) ternary composite with rich heterogeneous interfaces is constructed by combining solvothermal reaction, in-situ polymerization, annealing treatment with subsequent hydrothermal reaction. The research results have shown that the obtained NRGO/ZnFe2O4@NC ternary composite exhibits a unique core-shell structure and excellent EMW absorption performance. At a thickness of 2.61 mm, the maximum effective absorption bandwidth can reach 7.2 GHz, spanning the entire Ku-band and a portion of the X-band, and the minimum reflection loss is –61.1 dB, which is superior to most reported RGO-based EMW absorbers. The excellent EMW absorbing ability is mainly ascribed to the optimized impedance matching and the enhanced polarization loss caused by the abundant heterogeneous interfaces and structural defects derived from heteroatomic nitrogen doping. Furthermore, the radar cross section in the far field is simulated by a computer simulation technique. This study provides a novel way to prepare core-shell magnetic carbon composites as highly efficient and broadband EMW absorbers.