Electromagnetic Microwave Absorption Research Articles

Glucose derived carbon encapsulated boron nitride core-shell composites for efficient electromagnetic microwave absorption

Hexagonal boron nitride (h-BN) has the advantages of outstanding insulation, high thermal conductivity and excellent chemical stability, which promote the wide application of h-BN in thermal interface electronic packaging and other related fields. However, due to the poor dielectric loss ability of h-BN, which leads to its weak absorption capacity of electromagnetic waves (EMW), so it limits its practical application in related advantageous fields. In this paper, glucose-derived carbon-encapsulated BN core-shell composites (C@BN) were prepared by a simple hydrothermal reaction followed by high-temperature pyrolysis. The dielectric loss capacity of the C@BN was investigated by manipulating the concentration of glucose solution and pyrolysis temperature. Specifically, by adjusting the glucose derived carbon defect to induce polarization loss and impedance matching performance, so that more EMW entering the interior of the composite is absorbed and dissipated. The results show that C@BN obtained at 800 °C shows the best EMW absorption performance when the concentration of glucose solution is 3.6 wt%. The minimum reflection loss value (RLmin) is −43.5 dB and the maximum width effective absorption bandwidth (EABmax) of 6.72 GHz. Therefore, this study provides a reliable reference for the preparation of h-BN based EMW absorbing materials.

Enhanced electromagnetic wave absorption of magnetite-spinach derived carbon composite

The high density, high cost, and environmental pollution hinder the application of iron-based electromagnetic wave-absorbing materials. Although bio-carbon is a green and lightweight dielectric wave-absorbing material, the wave-absorbing performance of bio-carbon is still limited. This work successfully combined magnetite Fe3O4 with porous carbon derived from spinach stem using hydrothermal and calcination methods. This process optimizes the matching of the dielectric constant and magnetoconductivity of the as prepared composite material, resulting in a significant improvement in electromagnetic microwave absorption capacity. XRD, SEM, TEM, XPS, VSM and EMW absorption network analyzer are used to detect and characterize the samples. The composite material shows a excellent minimum reflection loss value of −48.81 dB and an efficacious absorption bandwidth of 4.73 GHz at the optimal raw material ratio. The tests also show the porous structure of the sample with the coercivity and saturation magnetization of 29.36 Oe and 10.75 emu/g, respectively. The test results indicate that the excellent electromagnetic wave absorption is due to the synergistic effect of multiple reflection, Debye relaxation, and interfacial polarization. This Fe3O4-bio-carbon composite is cheap and simple to prepare, and it also has excellent wave absorption performance. Therefore, it shows great application potential in civilian and military electromagnetic wave absorption fields.

Synthesis of Ti3C2Tx-MXene/PAN-derived double-loss Co/CeO2/TiO2/CNFs nanocomposites for enhanced microwave absorption performance

With the advancement of wireless communication and electronic equipment, microwave absorption materials (MAMs) have more and more broad applications in related fields. Ti3C2Tx-MXene with unique two-dimensional structure and excellent dielectric properties is often used as a precursor of nano-TiO2, which is a potential MAMs. Carbon nanofibers, as a one-dimensional material, have great electrical conductivity and can form interconnected three-dimensional conductive networks. In this study, Ti3C2Tx-MXene was prepared by in-situ HF etching method, and further combined with the benefits of Co, Ce metals, and carbon nanofibers. Co/CeO2/TiO2/CNFs were prepared via a facile technique for electromagnetic microwave (EM) absorption, exhibiting excellent EM absorption performance due to the synergistic effects of dielectric and magnetic properties. The minimum reflection loss (RLmin) and effective absorption bandwidth (EAB) reache -63.35 dB (11.2 GHz) and 3.6 GHz (9.5-13.1 GHz), with a thickness of only 2.35 mm and a filling rate of 30 wt.%, while the maximum EAB reaches 5.4 GHz (12.4-17.8 GHz) with a thickness of 1.82 mm, covering nearly the entire Ku band. By offering a novel strategy to the creation of brand-new, high-performance MAMs based on 1D carbon nanofibers with dielectric/magnetic synergy, this work is believed to support the development of upcoming MAMs.

Facile synthesis of vaterite CaCO3 microspheres from carbon capture and solid waste utilization towards microwave absorption and dye wastewater adsorption

Mineralization of CO2 to minerals like calcium carbonate (CaCO3) has been considered as an effective approach to combat global warming. In this paper, Ca2+ ions were firstly extracted from waste carbide slag, and then facilely transformed to vaterite CaCO3 via disperse bubbling carbonization method assisted with an air stone. By optimizing the reaction conditions, highly mono-dispersed vaterite CaCO3 microspheres (VCMs) were obtained. These microspheres consisted of aggregated CaCO3 nanocrystals, bearing a mesoporous structure. As a proof-of-concept, these mesoporous microspheres were utilized for dye adsorption and electromagnetic (EM) microwave absorption. For the former, the VCMs were used to adsorb Congo red, yielding a fast adsorption time of 9 min and a high adsorption capacity of 138.77 mg/g. For the latter, EM microwave dielectric parameters were measured, and dye-adsorbed VCMs exhibited better microwave-absorption performance with a minimum reflection loss of −43.2 dB, about 3 times of pristine vaterite. To the best of our knowledge, this is the first report of solid-waste-derived VCMs as microwave absorbent and dye adsorbent. Considering the low-cost, eco-friendly and facile preparation and effective utilization of VCMs, our work provides a promising strategy for large-scale carbon capture, solid waste utilization, and treatment of microwave and wastewater pollution.

Superior microwave absorption properties of anisotropic Y2Fe16‒xCoxSi/paraffin composites by orientation tuning

Y2Fe16-xCoxSi/paraffin composites were prepared by three different orientation methods. The effect of these orientation methods and the magnetocrystalline anisotropy of Y2Fe16‒xCoxSi alloys on the electromagnetic parameters and the microwave absorption properties were investigated. The results demonstrated that orientation tuning improved the electromagnetic parameters and microwave absorption properties. Anisotropy in dielectric properties and magnetic properties of Y2Fe16-xCoxSi/paraffin composites were achieved by tuning the orientation of Y2Fe16-xCoxSi powders. The planar and conical anisotropic materials had superior microwave absorption properties than uniaxial anisotropic materials for the same orientation method. The Y2Fe16‒xCoxSi/paraffin composite had an effective absorption bandwidth of 8.4 GHz (9.6–18 GHz) and a reflection loss of ‒59.6 dB which can almost cover the X–Ku bands and exceed the performance of many reported absorbing materials, showing its great prospects for microwave absorption in the X–Ku bands.

A green mediated synthesis of glass fiber‐nickel ferrite‐ polyaniline ternary composite: An excellent thermal stability and outstanding electromagnetic interference shielding performance

AbstractThe present study reports the preparation of a ternary composite with enhanced shielding performance toward electromagnetic waves using in situ polymerization of aniline on fiber‐ferrite binary composite. The polymerization is carried out in a green medium lime juice, which acts as an efficient dopant. The composite is amalgamated with varying weight percentages of ferrite (ranging from 25% to 100%) while maintaining a constant weight percentage of fiber. The presence of the fiber in the binary and ternary composite could enhance the thermal stability of the material, highlighting its applicability in a wide range of temperatures. The DC conductivity, AC conductivity, and dielectric properties are investigated, revealing significant performance enhancements. The ternary composite demonstrates excellent conductivity in the range of 10−210−1 S/cm, attributed to the polaron/bi‐polaron interaction paradigm. Furthermore, the electromagnetic interference shielding, microwave absorption, and reflection capabilities of the composites are assessed within the frequency range of 8–12 GHz. The optimized composite, featuring aniline (0.4 M) and glass fiber with ferrite in a 1:1 ratio, exhibits an outstanding shielding value of 32 dB. These results point toward the potential of this ternary composite material as an effective shield against electromagnetic pollution.

Tailoring permittivity and permeability of M-type hexagonal ferrite and 2D Ti3C2Tx MXene composites for broadband microwave stealth performance

In this study, owing to the significant advantages of heterogeneous interface engineering for customizing the electromagnetic parameters and microwave absorption properties, high magnetic lossy cobalt/zinc-doped hexagonal ferrite flakes were successfully anchored on two dimensional Ti3C2Tx with varying mass ratios. Inorganic Ti3C2Tx MXene was synthesized through the hydrofluoric acid etching process, and doped hexagonal ferrite was prepared by a solid-state sintering route leading to electrostatic bonding with Ti3C2Tx particles. Scanning electron microscopy revealed that the MXene surface strongly adhered to the ferrite particles. By adjusting the ratio of ferrite to Ti3C2Tx, it is feasible to optimize electromagnetic parameters, as required. Specifically, doped ferrite@4% Ti3C2Tx MXene composite exhibited remarkable absorption performance; the maximum reflection loss (RL) was −49 dB at 15.2 GHz with a thickness of 1.9 mm. The effective bandwidth corresponding to the RL values below −10 dB is 8.3 GHz (from 9.7 GHz to 18 GHz) at a single thickness of 2 mm, and below −15 dB is 6.4 GHz (from 10.7 GHz to 17 GHz), outlining the prospect for application as an electromagnetic wave absorber. Radar cross-section (RCS) simulation was performed with microwave incident angles ranging from 0 to 360°. The results demonstrate a reduction in RCS of up to −47.8 dBsm at a 60° incident angle. This study develops a new approach for constructing multi-component heterostructure composites with tailored electromagnetic parameters as a superior and modulated radar stealth material.

3D-printed conical structure absorber based on NFG/Fe3Si/SiCnw ternary composites for multifunctional integrated electromagnetic microwave absorption

The wave absorbers with dual functions of structural load-bearing and radar absorption have become the solution strategy to cope with the increasingly complex electromagnetic environment. In this paper, a conical structure absorber based on natural flake graphite (NFG)/Fe3Si/SiCnw ternary composites was successfully prepared by selective laser sintering (SLS) 3D printing technique starting from multi-scale design. From the material level, the in-situ grown one-dimensional SiC nanowires effectively improve the dielectric properties of the material, which increases the magnetic/dielectric loss synergy together with the magnetic material Fe3Si. The minimum reflection loss is −54.21 dB and the effective absorption bandwidth (EAB) is 4.6 GHz when the thickness is 1.5 mm. The unit structure of the conical structure absorber was structurally designed and experimentally verified at the structural level, and broadband electromagnetic absorption at 14.45 GHz was achieved and the compressive yield stress was 5.21 MPa. In addition, the EAB of both transverse electric-polarization (TE) and transverse magnetic-polarization (TM) under the variation of incidence angle from 0 to 50° exceeded 12 GHz, indicating that the conical structure absorber has excellent wide-angle absorption properties. The broadband microwave absorption performance of conical structure absorbers is attributed to the synergistic enhancement effect of improved impedance matching on the macroscopic scale and multiple electromagnetic loss mechanisms on the microscopic scale. The conical structure absorber prepared by SLS achieves material-structure-function integration of electromagnetic microwave absorption, and the multifunctional integrated design contributes to the practical application of stealth technology in the field of industrialized electromagnetic microwave absorption.

Efficient electromagnetic wave absorption of polypyrrole/low-reduction graphene oxide composites through dielectric properties modulation

Graphene oxide (GO) is widely used in electromagnetic microwave absorption (EMA) materials due to its abundant oxygen-containing functional groups and defects. Its conductivity, surface functional groups and defect density can be modified by controlling reduction degree to modulate its electromagnetic properties. However, the thermal reduction temperature needed is often too high, exceeding the Curie temperature of magnetic materials, which makes further compounding difficult. Polypyrrole (PPy), as a conductive polymer with high electrical conductivity, is widely used in EMA field and can help regulate the dielectric properties of materials. In this paper, a series of PPy/GO composites with different ratios and reduction degrees were prepared by in situ polymerization and thermal reduction, and their EMA properties were investigated. At a loading amount of 7.5 wt%, the maximum reflection loss of PPy/rGO composites can reach −66.64 dB, and the effective absorption bandwidth can reach 6.74 GHz with a reduction temperature of only 400 °C. Furthermore, the unreduced sample also has excellent absorption performance, which has a wide range of applications for future one-step compositing with magnetic materials in low reduction temperature.

Organosilane waste-derived SiCnws/SiOC composites with enhanced electromagnetic wave absorption performance

SiCnws/SiOC nanowires composites with a 3D network structure, exhibiting enhanced electromagnetic microwave absorption properties, were synthesized using carbothermal reduction. The solid precursor, organosilane waste, was employed, enabling cost-effective and environmentally friendly production. The structure and morphology of SiCnws/SiOC nanowires composites were extensively investigated by XRD, SEM, TEM, XPS spectra, and Raman spectra. Moreover, the composite demonstrated superior electromagnetic wave absorbing properties, including wide effective absorption bandwidth (EAB) of 2.73 GHz, strong minimum reflection loss (RLmin) of −52.66 dB, and thin thickness of 2.40 mm. These excellent electromagnetic wave attenuation properties stem from the synergistic strategy of dielectric and conductive losses, resulting from the unique 3D network heterostructural architecture. This work not only offers improved EMW absorption solutions but also contributes to waste recycling and resource recovery.

Component modulation and integrated multidimensional heterostructures of bimetallic MOFs derived 0D Co3ZnC/Co encapsulated in 2D CNTs-grafted 3D N-doped porous carbon polyhedron for high-efficient microwave absorption

Component modulation and multidimensional structural design are effective strategies to regulate the electromagnetic parameters and impedance matching, resulting in high-efficient microwave absorption. Herein, multidimensional integrated Co3ZnC/Co@C heterostructures compounding of 0D Co and Co3ZnC NCs, 1D CNTs and 3D porous carbon polyhedrons were fabricated by pyrolysis of bimetallic MOFs. Co and Co3ZnC NCs are uniformly encapsulated in CNTs-grafted porous carbon polyhedrons, forming 0D-1D-3D integrated heterostructures. The Co3ZnC/Co@C composites show component-modulated electromagnetic parameters and microwave absorption properties, which can be simply regulated by adjusting the ratio of Co/Zn in the MOFs precursor. With a filling ratio of 30 wt%, the optimal Co3ZnC/Co@C heterostructures show a minimum reflection loss (RL) value of −66.78 dB at 7.43 GHz with a thickness of 4.5 mm, located at the C band. The maximum effective absorption bandwidth (RL≤−10 dB) is up to 4.8 GHz (12.9–17.7 GHz) at only 2.0 mm. The high-efficient microwave absorption performance is attributed to that the multidimensional integrated heterostructures can sufficiently maximize the synergistic effects of each component. The uniformly distributed 0D Co and Co3ZnC NCs can promote magnetic loss and interfacial polarization. 1D CNTs are beneficial to enhance the conductive loss. 3D porous carbon polyhedrons grafted with CNTs are favored to promote the scattering of microwaves and impedance matching. These findings suggest a new insight to achieve high-performance microwave absorption by modulating the component and integrating multidimensional structures.

Flexible regulation engineering of titanium nitride nanofibrous membranes for efficient electromagnetic microwave absorption in wide temperature spectrum

Flexible regulation engineering of titanium nitride nanofibrous membranes for efficient electromagnetic microwave absorption in wide temperature spectrum

Large Microsphere Structure of a Co/C Composite Derived from Co-MOF with Excellent Wideband Electromagnetic Microwave Absorption Performance.

In the field of electromagnetic wave (EMW) absorption, carbon matrix materials based on metal-organic frameworks (MOFs) have drawn more interest as a result of their outstanding advantages, such as porous structure, lightweight, controlled morphology, etc. However, how to broaden the effective absorption bandwidth [EAB; reflection loss (RL) ≤ -10 dB] is still a challenge. In this paper, large microsphere structures of a Co/C composite composed of small particle clusters were successfully prepared by the solvothermal method and annealing treatment. At a filling ratio of 40 wt %, the Co/C composite shows attractive microwave absorption (MA) performance after being annealed at 600 °C in an atmosphere of argon. With an EAB of 6.32 GHz (9.92-16.24 GHz) and a thickness of just 2.57 mm, the minimum RL can be attained at -54.55 dB. Most importantly, the EAB can attain 7.12 GHz (10.88-18.0 GHz) when the thickness is 2.38 mm, which is larger than that of the majority of MOF-derived composites. The superior MA performance is strongly related to excellent impedance matching and a higher attenuation constant. This study provides a simple strategy for synthesizing a MOF-derived Co/C composite with a wide EAB.

MnFe2O4/polyaniline/diatomite composite with multiple loss mechanisms towards broadband absorption.

The research and development of absorbing materials with high absorbing capacity, wide effective absorption bandwidth, and lightweight has always been interesting. In this research, a facile hydrothermal method was used to prepare MnFe2O4, and the grain size of MnFe2O4 decreased with increasing hydrothermal temperature. When the size of MnFe2O4 nanoparticles is less than 10nm, its quantum size effect and surface effect make its electromagnetic microwave absorption performance greatly optimized. When the thickness of MnFe2O4-110 °C is 2.57mm, the minimum reflection loss (RLmin) is -35.28 dB. Based on this, light porous diatomite and a three-dimensional polyaniline network are introduced. Diatomite is used as the base material to effectively reduce the agglomeration of MnFe2O4 quantum dots. The relatively high surface area introduced by a three-dimensional network of polyaniline promotes the orientation, interfacial polarization, multiple relaxation, and impedance matching, thereby generating further dielectric loss. Additionally, the magnetic properties of manganese ferrite and the strong electrical conductivity of polyaniline play an appropriate complementary role in electromagnetic wave absorption. The RLmin of MnFe2O4/PANI/diatomite is -56.70 dB at 11.12GHz with an absorber layer thickness of 2.57mm. The effective frequency bandwidth (RL < -10 dB) ranges from 9.21 to 18.00GHz. The absorption mechanism indicates that the high absorption intensity is the result of the synergistic effect of impedance matching, conduction losses, polarization losses, and magnetic losses.

Engineering Phase to Reinforce Dielectric Polarization in Nickel Sulfide Heterostructure for Electromagnetic Wave Absorption.

Engineering phase transition in micro-nanomaterials to optimize the dielectric properties and further enhance the electromagnetic microwave absorption (EMA) performance is highly desirable. However, the severe synthesis conditions restrict the design of EMA materials featuring controllable phases, which hinders the tunability of effective absorption bandwidth (EAB) and leads to an unclear loss mechanism. Herein, a seed phase decomposition-controlled strategy is proposed to induct nickel sulfide (NiSx) absorbers with controllable phases and hollow sphere nature. Transmission electron microscopy holography and theoretical calculations evidence that the reconstruction of atoms in phase transition induces numerous heterogeneous interfaces and lattice defects/sulfur vacancies to cause varied work functions and local electronic redistribution, which contributes to reinforced dielectric polarization. As a result, the optimized NiS2/NiS heterostructure enables enhanced EM attenuation capability with a wide EAB of 5.04GHz at only 1.6mm, compared to that of NiS2 and NiS. Moreover, the correlation between EAB and NiS phase content is demonstrated as the "volcano" feature. This study on the concept of phase transition of micro-nanomaterials can offer a novel approach to constructing highly efficient absorbers for EMA and other functionalities.

Synthesis and microwave absorption performance of heat-treated RF/SiO2 aerogels

The well-designed composite with satisfactory electromagnetic microwave absorption at high temperatures remains a serious challenge. Herein, we fabricated a resorcinol-formaldehyde/silica dioxide composite aerogel (RF/SiO2) with a three-dimensional network structure using sol-gel, atmospheric pressure drying technique as well as heat-treated processes to achieve enhanced microwave absorption capabilities in the low frequency range. The pristine RF/SiO2 aerogel presented a typical micropores structure with a surface area, porous volume, and density of 146.82 m2/g, 62.40%, and 0.28 cm3/g, respectively. Remarkably, the RF/SiO2 aerogel showed an effective absorption bandwidth of 3.56 GHz and a minimum reflection loss value of −46.10 dB at 2.25 mm after being heat-treated at 1500 °C, while the maximum effective absorption bandwidth was 3.60 GHz at 2.30 mm. The intricate three-dimensional networks possessed remarkable impedance matching, multiple attenuation mechanisms, interfacial polarization, and dielectric loss, which were attributed to the exceptional ability to absorb electromagnetic microwaves. It offered a fresh approach to creating adaptable and effective microwave absorption materials in military defense.

Enhancing electromagnetic absorption in microwave of epoxy resin through incorporated surface modified aluminum oxide nanoparticles

The development of novel nanomaterials with superior reflection loss (RL), thin thickness, wide bandwidth, and low density has recently received significant attention in an effort to increase their effectiveness in electromagnetic (EM) microwave absorption while maintaining an easy manufacturing process. Naturally, using conventional materials with magnetic or dielectric loss makes it difficult to achieve the last criterion and limitations the thickness of the absorber and mass production. In this work, microwave nanocomposites samples were prepared on epoxy resin with different percentages of the nanoparticles of aluminum oxide (epoxy/Al2O3) with surfaces treated by amino propyl and silane. The surface treatment was carried out to improve the adhesion, morphology, and EM properties of the samples to enhance the microwave absorption and the Shielding Effectiveness (SE). Therefore, the treated sample can be considered as potential candidate for high frequency EM absorption applications. Then, the study is followed by structural, morphological, thermal, and electrical characterization of the prepared samples in order to enhance the performances of the latters. The EM absorption and the shielding effectiveness were done in the X band frequency (8 GHz-12 GHz). The obtained results confirmed that the nanocomposites treated samples exhibit higher EM absorption performance and better electrical characteristics. Overall, these results put forward the role played by the addition of the nanoparticles films as high-performance materials in electronic devices and EM applications.

Facile synthesis of FeNi nanoparticle-loaded carbon nanocomposite fibers for enhanced microwave absorption performance

The advantages of Fe, Ni metals and one-dimensional (1D) carbon materials are combined in this study using a simple method to prepare FeNi/C nanofibers for electromagnetic microwave (EM) absorption. The prepared FeNi/C nanofibers exhibit excellent EM absorption performance under dielectric/magnetic synergistic effect. At a frequency of 13.3 GHz, the minimum reflection loss (RLmin) reaches -57.15 dB, and effective absorption bandwidth (EAB) is as high as 4.0 GHz (12.5–16.5 GHz), with a thickness and filling rate of only 1.6 mm and 30 wt.%, respectively. Analysis shows that the EM absorption performance of FeNi/C nanofibers far exceeds that of single-component nanofibers and pure carbon fibers, and the excellent EM absorption performance is due to its unique microstructure and excellent electromagnetic properties. The FeNi alloy loaded on carbon nanofibers forms rich heterogeneous interfaces, and the three-dimensional (3D) conductive network composed of 1D carbon fibers increases the migration path of electrons. In addition, FeNi alloy, as an impedance regulation factor, strengthens the dielectricity of the carbon matrix while providing multidimensional magnetism, achieving impedance matching. This work is thought to contribute to the promotion of emerging absorbers by providing a novel strategy for the development of new 1D magnetic carbon-based high-performance EM absorbing materials.

Surface chemistry engineering and the applications of MXenes

MXenes have captured extensive attention in various fields by virtue of unique hydrophilicity, high conductivity and tunable surface terminations. In this review, the state-of-the-art progresses of designing functional MXenes have been summarized. Firstly, the synthesis methods of MXenes are summarized and classified into HF etching, in-situ HF etching and fluoride-free etching approaches based on the effect on the surface chemistry of MXenes. Secondly, the factors that affect the surface termination groups are discussed, including synthesis methods, heat treatment temperature and atmosphere. Thirdly, this review gives an overview of the synthetic routes of functional MXenes including termination modification by synthesis methods and heat treatment, heteroatom (N, S, or P) doping, cation and organic molecule intercalation and hybridization with polymer, which inhibit restacking and increase active sites for intrinsically enhancing the inherent physical and chemical properties of MXenes. Finally, the applications with respect to energy storage and conversion, catalysis, sensors, electromagnetic interference shielding and microwave absorption of functional MXenes are introduced. Additionally, the critical challenges and development prospects of functional MXenes are also highlighted.

Simple fabrication of cobalt–nickel alloy/carbon nanocomposite fibers for tunable microwave absorption

A series of CoNi/C nanocomposite fibers with different Co and Ni ratios were successfully prepared by electrospinning and carbonization techniques for the study of electromagnetic microwave (EMW) absorbing materials. We systematically studied the influence of Co and Ni content on the microstructure, chemical composition, magnetic properties, and EMW absorption characteristics of the samples. The results showed that CoNi/C nanocomposite fibers obtained excellent EMW absorption ability through the reasonable design of the composition, and the Co/Ni ratio significantly affected the microstructure and EMW absorption performance. When the Co/Ni ratio was 1/3, the minimum reflection loss (RLmin) is −71.2 dB (2.4 mm, 13.4 GHz), and the maximum effective absorption bandwidth (EAB, RL＜-10 dB) is up to 5.9 GHz (2.2 mm, 12.1–18 GHz), covering almost the entire Ku band. This study demonstrated the enormous potential of one-dimensional structure in the field of EMW absorption. In addition, the CoNi/C nanocomposite fiber synthesized using a straightforward and low-cost method not only has excellent EMW absorption performance but also has the potential for practical application. The results of this study provide a simple and effective approach for designing high-performance EMW absorbing materials.