Electromagnetic Wave Absorption Materials Research Articles

Ultrabroad electromagnetic absorbing core-shell SiC@SiO2 nanocomposites derived from in situ oxidation SiC whiskers

The amazing developing electromagnetic technology has brought severe challenges to the military and civilian fields, efficient electromagnetic wave absorption (EWA) materials with high-temperature resistance are urgent needed. In this paper, SiC@SiO2 nanocomposites with unique core-shell structures were successfully prepared using a straightforward method by in situ oxidation SiC whiskers. By regulating the sintering temperature and oxidation time, the microstructures and EWA performance of SiC@SiO2 nanocomposites were explored. The results show that the core-shell SiC@SiO2 nanocomposites obtained after sintering at 1200 ℃ for 0.5 h exhibits the best EWA performance, where the minimum reflection loss (RLmin) of −36.80 dB at the thickness of 2.68 mm and the effective absorption bandwidth (RL<-10 dB, EAB) of 9.85 GHz at a matching thickness of 4.24 mm. Specially, the EAB can reach up 10.98 GHz with the filling content of only 10%, which surpasses most SiC-based absorbers. The ultrabroad absorbing bandwidth can be attributed to that the unique core-shell structures of SiC whiskers with in-situ grown SiO2 layers on the surface provide good impedance matching, multiple reflection and scattering and interface polarization effects. This work provides a new strategy for the design of high temperature resistant absorbing materials.

Dual-step Redox Engineering of Two-Dimensional CoNi-Alloy Embedded B, N-Doped Carbon Layers towards Tunable Electromagnetic Wave Absorption and Light-Weight Infrared Stealth Heat Insulation Devices.

Two-dimensional layered metallic graphite composites as promising electromagnetic wave absorption materials (EWAMs) for their combined properties of abundant interlayer free spaces, rich metallic polarized sites and high conductivity, but the controllable synthesis remains rather challenging. Herein, a dual-step Redox engineering strategy was developed by employing cobalt boron imidazolate framework (Co-BIF) to construct a two-dimensional CoNi-alloy embedded B, N-doped carbon layers (2D-CNC), as a promising EWAM. In the first step, a chemical etching oxidation process on Co-BIF was used to obtain an optimized 2D-CoNi-layered double hydroxide (2D-CoNi-LDH) intermediate and in the second, high-temperature calcination reduction was implemented to modify graphitization the degree of the 2D-CNC. The obtained sample delivers superior reflection loss (RLmin) of -60.1dB and wide effective absorption bandwidth (EAB) of 6.24GHz. The synergy mechanisms of interfacial/dipole polarization and magnetic coupling were in-depth evidenced by the hologram and Lorentz electron microscopy, revealing its significant contribution on multireflection and impedance matching. Further theoretical evaluation by COMSOL simulation in different fields based on the dynamic loss process towards the test ring reveals the in situ EW attenuation process. This work presents a strategy to develop multifunctional light-weight infrared stealthy aerogel with superior pressure-resistant, anti-corrosion and heat-insulating properties for future applications. This article is protected by copyright. All rights reserved.

Constructing multiple heterogeneous interfaces in one-dimensional carbon fiber materials for superior electromagnetic wave absorption

Due to impedance mismatch and a single loss mechanism, carbon fiber fails to meet the requirements for efficient absorbers in terms of lightweight construction and broad absorption band. In this study, we have successfully prepared one-dimensional beaded SiO2@SiC@C nanofiber (SSCF) composites with multiple heterogeneous interfaces by employing the electrospinning-carbothermal reduction method. The beaded SSCF composites effectively address the impedance mismatch issue by controlling silicon dioxide and silicon carbide through carbothermal reduction. This optimization enriches the defects and interfaces of carbon fibers composites, consequently enhancing the electromagnetic wave absorption performance. The SSCF composites demonstrate remarkable performance, with a minimum reflection loss of -59.53 dB at a matched thickness of 2.21 mm and a maximum absorption bandwidth of 6 GHz. This outstanding performance is attributed to the synergistic effects of the multi-phase composition, bead structure, and one-dimensional network structure. These features not only optimize impedance matching but also enhance defect loss, interface polarization loss (SiC/SiO2, C/SiO2, SiC/C, C/Air), conduction loss, and relaxation loss of the SSCF composites. Furthermore, radar cross-section analysis utilizing computer simulation technology confirms the excellent attenuation of microwave energy by the SSCF composites under realistic far-field conditions. This study provides valuable insights for designing efficient one-dimensional carbon-based electromagnetic wave absorbers.

Magnetic media synergistic carbon fiber@Ni/NiO composites for high-efficiency electromagnetic wave absorption

Electromagnetic wave (EMW) absorbing materials have garnered significant attention for their potential applications in information security and military stealth fields. However, the development of highly efficient EMW absorbing materials possessing characteristics such as being “thin, lightweight, broadband and strong” remains a considerable challenge. Addressing this challenge involves the construction of low-dimensional composite material systems, which proves to be an effective approach. Carbon fiber (CF) is highly regarded for its light weight. In this study, we developed a simple and innovative sol–gel strategy to fabricate CF@Ni/NiO composites. The results demonstrate that the incorporation of Ni/NiO particles into CF materials substantially enhances the ferromagnetic properties of CF@Ni/NiO composites. An optimum reflection loss (RL) of CF@Ni/NiO-3 is −55.58 dB at 15.4 GHz with a corresponding thickness of merely 1.7 mm. An effective absorption bandwidth (EAB) reaches a maximum of 6.0 GHz at a thickness of 1.8 mm. Meanwhile, the radar cross section (RCS) reduction value at 6 GHz reaches 29.92 dB m2. The uniform distribution of Ni/NiO nanoparticles not only establishes a magnetic coupling network but also creates abundant heterogeneous interfaces with CF, thereby enhancing interfacial polarization. The successful fabrication of CF@Ni/NiO composites will facilitate the development and broad application of advanced electromagnetic wave (EMW) absorption materials in the aviation and aerospace sectors.

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 -48.81dB and an efficacious absorption bandwidth of 4.73GHz at the optimal raw material ratio. The tests also show the porous structure of the sample with the coercivity and saturation magnetization of 29.36Oe and 10.75emu/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.

Multiple birds with one stone: A new type of PPy/Fe3O4/rGO multifunctional composite fabric for wave absorption, UV resistance, anti-static and thermal insulation

To solve the problem of electromagnetic radiation pollution, it is especially important to develop electromagnetic wave-absorbing materials with excellent performance. The preparation of composite multifunctional textile materials with excellent wave-absorbing properties is one of the research hotspots for practical personal protection applications. In this work, PPy/Fe3O4/rGO polyester/cotton composite fabrics were prepared by impregnation, chemical reduction, chemical co-precipitation and in situ polymerization. When the thickness is 0.97 mm, the minimum reflection loss (RLmin) of PPy/Fe3O4/rGO polyester/cotton composite fabric is −12.12 dB, and the effective absorption bandwidth (EAB) is 4.7 GHz, which is excellent in wave absorption. Meanwhile, the PPy/Fe3O4/rGO polyester/cotton composite fabrics have excellent UV resistance (UV transmittance ratio of UVA and UVB bands as low as 0.02 %, UPF value of 100+), antistatic properties (static voltage half-life of 0.2 s), and excellent thermal management properties (thermal conductivity as low as 0.05796 W/(m·K)), and so on. The PPy/Fe3O4/rGO polyester/cotton composite fabrics prepared in this study are suitable for a variety of application scenarios, such as individual electromagnetic protection, individual protection in extremely cold environments, and individual heating physiotherapy, which is of great reference significance for the research of wearable individual protective textile materials.

Synergistic Enhancement of Electromagnetic Wave Absorption and Corrosion Resistance Properties of High Entropy Alloy Through Lattice Distortion Engineering

AbstractHigh entropy alloys (HEAs) are promising electromagnetic wave absorption (EMA) materials due to its designable crystal structure, variable electromagnetic properties, and excellent corrosion resistance. However, the impedance mismatch owing to the high electric and dielectric conductivity severely hinders the application of HEAs in the field of EMA. Herein, the lattice distortion of FeCoNiCu HEA is manipulated accurately by doping and annealing strategies to tailor the EMA properties. Significant lattice distortion is observed in the FeCoNiCuC0.37, which leads to a decrease in the electrical conductivity and the creation of abundant dipoles. Owing to the optimal impedance matching and boosted polarization loss, the FeCoNiCuC0.37 delivers a minimal reflection loss of −65.4 dB accompanied by an effective absorption bandwidth (EAB) of 6.81 GHz. After annealing at 200 °C, the EAB of the FeCoNiCuC0.37 is further increased to 7.99 GHz at 1.95 mm, which is better than that of most HEA‐based EMA absorbers reported so far. Moreover, it demonstrates excellent corrosion resistance owing to the more tortuous diffusion path of corrosive medium origin from lattice distortion. Thus, the study provides a new insight into designing high performance HEA‐based EMA materials with superior anti‐corrosion property by lattice distortion engineering.

Fe2AlB2@FeAl layered double hydroxides with core-shell heterostructures for electromagnetic wave absorption

The rapid development of high-performance materials has garnered considerable attention in addressing electromagnetic pollution. The construction of core-shell heterostructures is an effective approach for regulating the electromagnetic parameters of absorbers. However, these heterostructures usually lack a direct channel for charge transport between the core phase and the adhesive shell phase. Herein, Fe2AlB2@FeAl-layered double hydroxides with core-shell heterostructures were prepared using a top-down approach. The tightly connected FeAl-LDHs nanosheets to the Fe2AlB2 parent phase improved electronic transport. Compared with raw Fe2AlB2, the spherical absorber with an embroidered structure demonstrated stronger reflection loss (-15.6 dB for Fe2AlB2, −58.6 dB for Fe2AlB2@FeAl-LDHs) and a broader effective absorption bandwidth (2.2 GHz for Fe2AlB2, 3.6 GHz for Fe2AlB2@FeAl-LDHs) due to the enhanced dielectric and magnetic losses. This study presents a practical method for designing new controllable core-shell heterostructures for electromagnetic wave-absorbing materials.

In Situ Loading of Ni3ZnC0.7 Nanoparticles with Carbon Nanotubes to 3D Melamine Sponge Derived Hollow Carbon Skeleton toward Superior Microwave Absorption and Thermal Resistance.

The simple and low-cost construction of a 3D network structure is an ideal way to prepare high-performance electromagnetic wave (EMW) absorption materials. Herein, a series of carbon skeleton/carbon nanotubes/Ni3ZnC0.7 composites (CS/CNTs/Ni3ZnC0.7) are successfully prepared by in situ growth of Ni3ZnC0.7 and CNTs on 3D melamine sponge carbon. With the increase ofprecursor, Ni3ZnC0.7 nanoparticles nucleate and catalyze the generation of CNTs on the surface of the carbon skeleton. The minimum reflection loss (RL) value of the S60min composite (loading time of 60 min) reaches -86.6dB at 1.6mm and effective absorption bandwidth (EAB, RL≤-10dB) is up to 9.3GHz (8.7-18GHz). The 3D network sponge carbon with layered micro/nanostructure and hollow skeleton promotes multiple reflection and absorption mechanisms of incident EMW. The N-doping and defects can be equivalent to an electric dipole, providing dipole polarization to increase dielectric relaxation. The uniform Ni3ZnC0.7 nanoparticles and CNTs play a key role in dissipating electromagnetic energy, blocking heat transfer, and enhancing the mechanical properties of the skeleton. Fortunately, the composite displays a quite low thermal conductivity of 0.09075Wm·K-1 and good flexibility, which can provide insulation and quickly recover to its original state after being stressed.

Recent research progress and prospect of graphene-based microwave absorbing materials

With the increasing use of electronic devices, electromagnetic wave pollution has become a hot topic of concern and discussion, and microwave absorption materials play an important role in civil and defense military fields. Therefore, the development of electromagnetic wave absorption materials with low density, thin thickness, wide effective bandwidth, and strong wave absorption performance has become the focus and goal of researchers. Graphene shows a unique two-dimensional structure, lightweight, large specific surface area, high electrical conductivity, and high thermal conductivity, which make it a promising electromagnetic wave-absorbing material. However, pure graphene material cannot meet the needs of practical applications due to bad impedance matching. Therefore, graphene is usually combined with other materials (such as carbon materials, magnetic metal, polymer, ferrite, and ceramic) to improve its wave absorption properties. In this review, we summarize recent research progress of different types of graphene-based microwave absorbing materials. In addition, the challenges and prospects for improving the microwave absorption properties of graphene-based composites are presented, which will be useful for those working in related fields.

Interface-induced dual-pinning mechanism enhances low-frequency electromagnetic wave loss

Improving the absorption of electromagnetic waves at low-frequency bands (2-8 GHz) is crucial for the increasing electromagnetic (EM) pollution brought about by the innovation of the fifth generation (5G) communication technology. However, the poor impedance matching and intrinsic attenuation of material in low-frequency bands hinders the development of low-frequency electromagnetic wave absorbing (EMWA) materials. Here we propose an interface-induced dual-pinning mechanism and establish a magnetoelectric bias interface by constructing bilayer core-shell structures of NiFe2O4 (NFO)@BiFeO3 (BFO)@polypyrrole (PPy). Such heterogeneous interface could induce distinct magnetic pinning of the magnetic moment in the ferromagnetic NFO and dielectric pinning of the dipole rotation in PPy. The establishment of the dual-pinning effect resulted in optimized impedance and enhanced attenuation at low-frequency bands, leading to better EMWA performance. The minimum reflection loss (RLmin) at thickness of 4.43 mm reaches -65.30 dB (the optimal absorption efficiency of 99.99997%), and the effective absorption bandwidth (EAB) can almost cover C-band (4.72 ~ 7.04 GHz) with low filling of 15.0 wt.%. This work proposes a mechanism to optimize low-frequency impedance matching with electromagnetic wave (EMW) loss and pave an avenue for the research of high-performance low-frequency absorbers.

Fabrication of MOF-rGO aerogels to enhance electromagnetic wave absorption by adjusting the morphology and structure of MOFs by electron transfer

Graphene and its derivatives have become the star materials in the field of electromagnetic wave (EMW) absorption, and have been widely studied because of their unique structure and excellent properties. However, the high electrical conductivity of graphene-based material leads to poor impedance matching performances, so it often needs to be annealed at high temperatures, which is a intricate procedure and cause the waste of energy. Herein, we develop a convenient strategy to synthesize metal organic framework-reduced graphene oxide (MOF-rGO) aerogels through facile hydrothermal and freeze drying procedure. Firstly, the excessive electrons on graphene can be transferred to MOF, in this way, no annealing is needed. Secondly, the morphology and structure of MOF can be regulated electronically to endow the material with rich heterojunction interfaces and enhance its interfacial polarization. Thirdly, the synthesized aerogels satisfy the requirements of thin thickness, low density and light weight. The fabricated Ni-MOF-rGO and FeNi-MOF-rGO aerogels exhibit remarkable EMW absorption performances with strong reflection loss (RL) and broad effective absorption band (EAB) at the thickness of 2.4 (−47.8 dB and 7.84 GHz) and 2.9 mm (−48.3 dB and 8.32 GHz) whereas the filling contents are just 5 %. Moreover, the attenuation capacity of the fabricated aerogels are verified through the radar-section simulation and the interfacial polarization loss are confirmed by the COMSOL analogue simulation. In a word, this work provides a new afflatus and inspiration for the design of graphene-based EMW absorption materials.

Metal–Organic Frameworks-Derived FeCo/C–CNT Nanocomposites Modified Epoxy Resin for Electromagnetic Protection Coatings for Buildings

Exploring an efficient electromagnetic protection strategy for buildings is of great significance to solve the problems caused by increasing electromagnetic pollution, as the rapid progress of technology continues. In this work, FeCo alloy/carbon–carbon nanotube (FeCo/C–CNT) nanocomposites, with significant microwave absorption performance, were successfully synthesized using a simple pyrolysis method involving FeCo–ZIF MOFs precursors and added to epoxy resin to prepare a novel electromagnetic wave absorption (EWA) coating. The minimum reflection loss (RLmin) of the coating applied on the surface of the ceramic tiles was −23.89 dB at 11.37 GHz and the effective absorption bandwidth (EAB) reached 8.85 GHz. Through microscopic characterization and analysis of the electromagnetic parameters of the FeCo/C–CNT nanocomposites, it was found that the EWA coating has an ultrabroad band wave absorption effect, mainly due to the comprehensive advantages of the polarization loss from CNTs, impedance matching, the dual loss synergy effect, and multiple reflection between the FeCo alloys, the carbon layer, and the CNTs. This study has successfully developed high-performance EWA materials and demonstrated the feasibility of an EWA coating applied to building surfaces, contributing to the improvement of electromagnetic protection functions of buildings.

Metamaterial Absorbers with Archimedean Tiling Structures: Toward Response and Absorption of Multiband Electromagnetic Waves.

With the continuous development of electromagnetic wave-absorbing materials, the design of artificial structures for electromagnetic absorbers based on the concept of metamaterials is becoming more abundant. However, in the design process, it is difficult to further broaden the effective absorption band due to the limitation that the traditional single-size structure responds to electromagnetic waves only in specific frequency bands. Therefore, in this paper, based on the moth-eye bionic hexagonal structure absorber with antireflection performance, an Archimedean tiling structure is designed to optimize it, and through the introduction of a variety of primitives with large differences in dimensions, a multifrequency band-response mechanism is achieved to enhance the multireflection mechanism, which can effectively broaden the absorption band and improve the wave absorption performance. Ultimately, the moth-eye bionic structure absorber optimized by (3.4.6.4) can achieve an effective absorption of 10.26 GHz at a thickness of 2 mm. This work presents a new idea for the design work of electromagnetic wave-absorbing metamaterials, which has a broad application prospect in the aerospace, electronic information countermeasures, communication, and detection industries.

Lightweight carbon nanotube/aramid nanofiber aerogel with superior electromagnetic wave absorption, thermal insulation, and flame resistance

Carbon nanotubes, presenting distinguished electromagnetic wave (EMW) loss capacity and light-weight advantage, are promising candidates for EMW absorption materials. However, poor dispersibility, inadequate processibility, and excessive permittivity leading to impedance mismatch limit the application of carbon nanotubes. Herein, branched aramid nanofiber (ANF) acting as a surfactant, gelling agent, and electromagnetic parameter regulator is utilized to ameliorate the performances of carboxylic multi-walled carbon nanotube (c-MWCNT). The c-MWCNT/ANF aerogels with anisotropic structures are assembled through electrostatic-repulsion-assisted dispersion, hydrogen-bond-induced gelation, unidirectional freezing, and freeze-drying. By adjusting the proportion of c-MWCNT and ANF to optimize the impedance matching and electromagnetic parameters, the composite aerogel with ultralow density (∼26.2 mg cm−3) shows an extraordinary minimum reflection loss of −60.43 dB and a maximum effective absorption bandwidth of 5.34 GHz along the vertical direction of oriented channels. Moreover, benefiting from high porosity and remarkable thermal stability, the aerogels possess prominent thermal insulation and flame resistance. This work provides a strategy for the advanced EMW absorption materials, which have great potential value for aerospace applications under harsh environments.

Nanopore construction in SiC aerogels for continuous dual-peak electromagnetic wave absorption with full Ku-band coverage

SiC aerogels have been extensively studied for electromagnetic wave (EMW) absorption because of their tunable dielectric properties. Continuous dual-peak EMW absorption can broaden the effective absorption bandwidth (EAB); however, few SiC aerogels have been reported to exhibit this phenomenon and the mechanisms to achieve this through microstructure design remain unclear. In this study, size-tunable nanopores were constructed in SiC aerogel by a simple carbothermal reduction method, which gradually increase with increasing reaction temperature. The mechanism of the nanopore formation in SiC aerogels is also discussed in detail. The optimized SiC aerogel prepared at a reaction temperature of 1550 °C exhibited continuous dual-peak EMW absorption with a maximum EAB of 6.24 GHz (11.76–18 GHz), full Ku-band coverage, and minimum reflection loss of −32.59 dB. This continuous dual-peak EMW absorption was ascribed to the overlap of the secondary peak caused by the nanopore-induced strong dielectric resonance and the main peak caused by SiC. The results of this study will provide inspiration for the design of microstructures for continuous dual-peak absorption in EMW absorption materials.

Polypyrrole/Fe3O4 nanocomposites anchored on graphene toward efficient electromagnetic wave absorption performance

The ternary nanocomposites of polypyrrole/Fe3O4/graphene (PPy/Fe3O4/RGO) have been prepared via a two-step method. PPy/Fe3O4 composites have been initially anchored on GO surface by chemical one-step method following by reducing GO. The electromagnetic wave absorption (EMWA) performance of composites can be tuned by adjusting the amount of pyrrole monomers. The maximum reflection loss of the PPy/Fe3O4/RGO-0.5 (pyrrole:0.5mL) composite is up to -66.0dB at 14.88GHz and the absorption bandwidths exceeding -10 dB were 5.76GHz with absorber thickness of 2.5mm. The investigation of the electromagnetic absorb-ability reveals that PPy/Fe3O4/RGO exhibits enhanced electromagnetic absorption properties compared to Fe3O4/RGO, which is mainly ascribed to the improved impedance matching, the enhanced interfacial effects and geometric effect. Furthermore, this strategy expands the scope of the electromagnetic wave absorption materials. It confirms that modification of graphene with PPy and Fe3O4 makes the ternary nanocomposites have a promising future in electromagnetic wave absorption materials.

Multifunctional graphene/Ti3C2Tx MXene aerogel inlaid with Ni@TiO2 core-shell microspheres for high-efficiency electromagnetic wave absorption and thermal insulation

The demand for high-performance electromagnetic wave absorbing (EMA) materials featured with strong attenuation ability, extended absorption bandwidth and ultralight property is imperative yet remains challenging. Herein, a three-dimensional hierarchically porous reduced graphene oxide (rGO)/Ti3C2Tx MXene aerogel embedded with Ni@TiO2 core–shell microspheres was prepared via directional freeze-drying followed by a mild annealing process. The divergence in structure and multicomponent dielectric/magnetic features bring about optimized impedance matching characteristic, multiple polarization and loss pathways, collectively contributing to the excellent absorption performance. As a result, the Ni@TiO2/MXene/rGO (NTMRG-2) aerogel exhibits optimized EMA capability with a maximal effective absorption bandwidth (EABmax) of 6.48 GHz at a lower loading level of 5 wt% in the supporting matrix, covering the whole Ku band. Additionally, it achieves a minimum reflection loss (RLmin) of −71.4 dB with a matching thickness of 2.04 mm. Moreover, the aerogel also exhibits an ultra-light density of 5.58 mg cm−3, superior thermal insulation capacity (close to air) and hydrophobicity, underscoring its potential for multiple applications in various scenarios.

Multiple relaxation behavior of Cf/mullite composites and their electromagnetic wave performance at high temperatures

Reliability and stability of electromagnetic wave absorption (EMA) materials used in high-temperature fields such as aircraft and aero-engines are of great interest. In this regard, the Cf/mullite composites with an opportune heterogeneous interface were fabricated using gel-casting and pressureless sintering techniques. The as-prepared composites exhibited excellent EMA performance with multiple relaxation behavior upon increasing testing temperature ranging from 25 °C to 800 °C (the minimum reflection loss (RLmin) of −62.67 dB with a thin thickness of 2 mm at 600 °C). The results demonstrated that the temperature-dependence complex permittivity with multiple relaxation characteristics plays a key role for the EMA performance evolution. The newly generated Cole-Cole semicircle and κ curves with an increasing number of intersections at zero values suggest that the polarization relaxation is enhanced with rising temperatures, thus improving the EMA capacity. It is believed that the Cf/mullite composite could be a new promising EMA material at high temperatures.

Regulating the Electronic Structure of MAX Phases Based on Rare Earth Element Sc to Enhance Electromagnetic Wave Absorption.

MAX phases are highly promising materials for electromagnetic (EM) wave absorption because of their specific combination of metal and ceramic properties, making them particularly suitable for harsh environments. However, their higher matching thickness and impedance mismatching can limit their ability to attenuate EM waves. To address this issue, researchers have focused on regulating the electronic structure of MAX phases through structural engineering. In this study, we successfully synthesized a ternary MAX phase known as Sc2GaC MAX with the rare earth element Sc incorporated into the M-site sublayer, resulting in exceptional conductivity and impressive stability at high temperatures. The Sc2GaC demonstrates a strong reflection loss (RL) of -47.7 dB (1.3 mm) and an effective absorption bandwidth (EAB) of 5.28 GHz. It also achieves effective absorption of EM wave energy across a wide frequency range, encompassing the X and Ku bands. This exceptional performance is observed within a thickness range of 1.3 to 2.1 mm, making it significantly superior to other Ga-MAX phases. Furthermore, Sc2GaC exhibited excellent absorption performance even at elevated temperatures. After undergoing oxidation at 800 °C, it achieves a minimum RL of -28.3 dB. Conversely, when treated at 1400 °C under an argon atmosphere, Sc2GaC demonstrates even higher performance, with a minimum RL of -46.1 dB. This study highlights the potential of structural engineering to modify the EM wave absorption performance of the MAX phase by controlling its intrinsic electronic structure.