Excellent Electromagnetic Wave Absorption Research Articles

Enhanced electromagnetic wave absorption properties of SiCN(Ni)/BN ceramics by in situ generated Ni and Ni3Si.

In this paper, the SiCN(Ni)/BN ceramic with excellent electromagnetic wave (EMW) absorption performance was successfully prepared. The Ni and Ni3Si were in situ formed by the introduction of nickel acetylacetonate (NA), which effectively improved the impedance matching performance of SiCN(Ni)/BN ceramics. The EMW absorption properties of the SiCN(Ni)/BN ceramics showed a trend of first increasing and then decreasing with the increase in content of NA. When the NA content reached 7 wt%, the impedance matching range of SiCN-7 was optimal. The minimum reflection loss (RLmin) of SiCN-7 reached -53.47 dB at 4.2 mm and the effective absorption bandwidth (EAB) was 2.32 GHz at 3.48 mm. Through the analysis of electrical conductivity, it was found that the proportion of polarization loss in dielectric loss was more than 99%. It is worth noting that the radar cross section (RCS) value of SiCN-7 absorber was lower than that of the perfect electrical conductor (PEC) plate in the range of -90-90°, and showed a larger coverage angle, indicating that it possessed a good practical application prospect in the field of electromagnetic wave absorption.

Fabrication of flower-like CoFe/C composites derived from ferrocene-based metal-organic frameworks: an in situ growth strategy toward high-efficiency electromagnetic wave absorption.

Magnetic/dielectric composites can achieve high-efficiency electromagnetic wave (EMW) absorption performance by integrating multiple mechanisms such as dielectric loss and magnetic loss. The bimetallic metal-organic frameworks (MOFs) assembled from ferrocene (Fc) derivative-based bridging ligands are considered ideal precursors for the preparation of magnetic/dielectric composites due to tailored alloy components with magnetic losses. Herein, a novel CoFe/C composite with nanoflower structures is successfully obtained via an in situ growth strategy to decompose an Fc-based bimetallic MOF assembled from 1,1'-ferrocene dicarboxylic acid as bridging ligands and Co2+ ions. Notably, the nanoflower structures of the obtained composites provide an effective path for the scattering and reflection of the EMW, thereby improving the impedance matching by combining dielectric and magnetic loss. The CoFe/C composite exhibits excellent EMW absorption performance and has a minimum reflection loss of -61.6 dB at 3.7 mm and an effective absorption bandwidth of 6.24 GHz at a corresponding thickness of 2.2 mm. Moreover, the obtained composite exhibits lightweight characteristics and a low radar cross-section. This work presents a novel method through Fc-based bimetallic MOF derivatives to design and develop novel magnetic/dielectric composites with efficient EMW absorption properties for comprehensive applications.

Polyimide-based porous carbon and cobalt nanoparticle composites as high-performance electromagnetic wave absorbers.

This study successfully utilized a straightforward approach, choosing liquid-liquid phase separation to build a porous structure and synthesize composite absorbers based on polyimide-based porous carbon and cobalt nanoparticles (designated as PPC/Co-700 and PPC/Co-800). A fine porous structure was achieved as a result of the excellent heat resistance of polyimide resulting in an excellent electromagnetic wave absorption ability of PPC/Co composites. The results obtained clearly indicated that PPC/Co-700 and PPC/Co-800 exhibit a porous structure with coral-like pores, enhancing both impedance matching properties and microwave attenuation abilities. This improvement in impedance matching conditions and dissipation capability is attributed to the synergistic effect of dielectric loss induced by carbon and magnetic loss induced by Co nanoparticles. PPC/Co-700 showed the strongest absorption performance with a minimum reflection loss of -59.85 dB (30 wt% loading, thickness of 3.42 mm) and an effective absorption bandwidth (EABW, RL ≤ -10 dB) of 6.24 GHz (30 wt% loading, thickness of 2.78 mm). Therefore, this work provides a facile strategy for the development of a promising absorbing material with outstanding electromagnetic wave absorption performance.

Tuning dielectric and electromagnetic absorption properties of SiC fiber by in-situ grown polycrystalline carbon nanowires

Silicon carbide fiber (SiCf) has a promising potential to develop structural electromagnetic wave (EMW) absorption materials. Tuning dielectric properties of SiCf is necessary to obtain excellent EMW absorption performances, which is always realized by the introduction of extra dielectric loss phases. Herein, in-situ grown polycrystalline carbon nanowires (CNW) as novel dielectric fillers, possessing moderate conductivity as well as efficient loss ability, were used to improve the EMW absorption performance of SiCf. When the content of CNW is suited, CNW can interconnect with each other and form a multiporous network on the surface of SiCf. Such a unique network makes a great contribution to good impedance matching as well as strong conductivity loss and polarization loss, which endows SiCf with an effective absorption broadband (EAB) of 4.14 GHz at a thickness of 3.0 mm, demonstrating superior EMW absorption performance than most previously reported SiCf/carbon hybrids.

Sr(Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)O3: A novel high-entropy perovskite oxide with enhanced electromagnetic wave absorption properties

Perovskite materials (ABO3) possess a wealth of elements selectable and exhibit a diverse range of octahedral transformations. The emergence of high-entropy perovskite ceramics provides a fresh perspective for advancing the field of wave-absorbing materials. In this study, we concentrate on the wet chemical synthesis of a high-entropy perovskite oxide, Sr(Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)O3, and investigate its crystal structure, microstructure, chemical composition, magnetic properties, and microwave absorbing capabilities. The results indicate that when sintered at a temperature of 1,350 °C, the sample achieves a minimum reflection loss of −54.0 dB at a frequency of 9.68 GHz, accompanied by a maximum effective absorption bandwidth (EAB) of 7.44 GHz at the thickness of 1.8 mm. The high-entropy design of the B-site induces distortions of oxygen vacancy and octahedral structure of the perovskite material. This leads to the fine tuning of its dielectric and magnetic properties, thereby endowing perovskite with excellent electromagnetic wave absorption capabilities. Consequently, perovskite emerges as a promising new electromagnetic wave absorption material with significant potential.

Construction of secondary heterojunction interface between 2D NiCo-LDH and MOF-derived 0D Co@NC for enhanced electromagnetic response

The development of hierarchical heterostructures to enhance the interfacial interactions between substrates and ligands is recognized as an effective approach for optimizing electromagnetic wave (EMW) absorption performance. Nonetheless, the advancement of novel EMW absorbers with ultrathin matching thickness (d < 1 mm), robust reflection loss (RL ≤ -50 dB), and a broad effective absorption bandwidth (EAB, RL ≤ -10 dB) continues to present a formidable challenge. In this work, we have manufactured Co@NC/NiCo-LDH absorbers featuring hierarchical hetero-interfacial structures. This was accomplished using a straightforward hydrothermal method that induced the in-situ growth of 2D NiCo-LDH nanosheet ligands on the surface of 0D Co@NC heterostructured substrates. Both 0D Co@NC heterostructures and 2D NiCo-LDH nanosheets are composed of small nanoparticles, creating many homogeneous and heterogeneous interfaces, and substantially augmenting interfacial polarization loss. The Co@NC/NiCo-LDH hierarchical hetero-interfacial structure demonstrates strong dielectric loss (interfacial polarization, conductive loss, dipolar polarization), magnetic loss (natural resonance and switched resonance), and excellent impedance matching. As a result, the Co@NC/NiCo-LDH heterostructure displays excellent EMW absorption characteristics with reflection loss (RL) values of -55.78 dB and -60.53 dB at matching thicknesses of 0.97 mm and 1.45 mm, respectively. The EAB value can reach 4.36 GHz. Furthermore, the Co@NC/NiCo-LDH absorber demonstrates outstanding radar wave attenuation performance through radar cross-section simulation (RCS). It achieves a maximum RCS reduction value of 30.96 dB m2. This research offers valuable insights into the EMW absorption mechanism of hierarchical hetero-interfacial structures, contributing to a deeper understanding of the design and utilization of multilevel heterostructures.

Tuning the microstructure of porous SiCnw/SiC fabricated by vat photopolymerization 3D printing for electromagnetic wave absorption

SiC is recognized as a viable material for electromagnetic wave (EMW) absorption due to its unique physicochemical properties. However, there are still some challenges at present, such as poor EMW absorption performance and difficulty in the fabrication of complicated structures for optimized EMW properties. Here, we presented a novel strategy through vat photopolymerization (VPP) 3D printing technology and carbothermal reduction to prepare porous SiCnw/SiC ceramics with controlled topologies and excellent EMW absorption properties. The gradient hole structure produced by carbothermal reduction facilitates material impedance matching regulation and improves incident wave multiple scattering as well as the in-situ grown SiCnw acts as the dipole center and improves incident wave dielectric loss. Porous SiCnw/SiC ceramics achieve improved EMW absorption performance with a minimum reflection loss (RL) of −57.67 dB at a thickness of 2.20 mm and with an effective absorption bandwidth (EAB) of 3.93 GHz at a thickness of 2.60 mm, covering almost the whole X-band, demonstrating outstanding EMW absorption properties. Furthermore, it exhibits the potential in the application of EMW absorbing devices with complex structure.

Superflexible porous PCSnf-Fe3O4/CNT-PANI BP/PCSnf-Fe3O4 sandwich composite films with excellent electromagnetic wave absorption performance based on integral assembly by electrospinning

Polycarbosilane nanofiber-ferroferric oxide (PCSnf-Fe3O4) films were assembled on both sides of carbon nanotube-polyaniline buckypaper (CNT-PANI BP) by electrospinning to obtain PCSnf-Fe3O4/CNT-PANI BP/PCSnf-Fe3O4 sandwich porous composites, with a diameter of 110–120 mm and a thickness of 150–200 µm. The Fe3O4 nanoparticles adhered on the PCS nanofibers formed a bamboo-like or plum-like structure. The PANI nanoparticles were uniformly embedded in the CNT network. Both PCSnf-Fe3O4 film skin layers were well bonded to the CNT-PANI BP core layer, with two main forms of the interlayer interface of rattan-like and root-like entanglement. The sandwich composite film (SCF) with 15.1 wt% Fe3O4 in the skin layers had a density of 0.97 g/cm3, a porosity of 61% and a total pore area of 30.1 m2/g, with a multimodal pore size distribution. The SCFs were superflexible, being tightly wound around a 4 mm diameter glass rod and repeated 100 times without damage. The absorption performance of the SCF was significantly improved by introducing Fe3O4 nanoparticles into its skin layers. The SCF with 11.8 wt% Fe3O4 in its skin layers achieved optimal dielectric and magnetic loss matching, with minimum reflection loss of − 43.54 dB and maximum effective absorption bandwidth of 6.97 GHz.

CNTs-improved electromagnetic wave absorption performance of Sr-doped Fe3O4/CNTs nanocomposites and physical mechanism

Electromagnetic wave pollution is a serious environmental problem, and it is urgent to develop high-efficiency electromagnetic wave absorption (EMA) materials. In this paper, carbon nanotubes (CNTs) were combined with Sr-doped Fe3O4 nanoparticles to form Sr-doped Fe3O4/CNTs nanocomposites with by hydrothermal method. After the characterization of microstructure and magnetic properties, EMA properties of Sr-doped Fe3O4/CNTs nanocomposites are investigated in detail. The well-dispersed CNTs lead to the uneven average grain size of Sr-doped Fe3O4 nanoparticles and a little decrease of saturation magnetization. While CNTs greatly improve EMA performance, and SFC1 sample exhibits the minimum reflection loss value of −65.64 dB at 6.32 GHz with the thickness of 3 mm. CNTs reduces the natural resonance of magnetic loss while increasing the permittivity, conductivity, and heterogeneous interfaces. As the result, Sr-doped Fe3O4/CNTs nanocomposites exhibit not only better impedance matching but also higher electric dipole polarization relaxation loss, interfacial relaxation loss, conductivity loss, and eddy current loss. In this way, the excellent EMA performance is attributed to the good impedance matching, intense dielectric loss and enhanced eddy current loss for Sr-doped Fe3O4/CNTs nanocomposites.

Metal–Organic Gel Leading to Customized Magnetic-Coupling Engineering in Carbon Aerogels for Excellent Radar Stealth and Thermal Insulation Performances

HighlightsFe3+, Co2+, H3BTC, and collagen peptide are used to achieve a one-step assembly of stable FeCo-MOG/CP by manipulating the complexation effect and solution polarity.By optimizing pyrolysis, two kinds of nitrogen-doped carbon aerogels loaded with virus-shaped and nanospherical magnetic particles are obtained.FeCo/Fe3O4/NC and FeCo/NC aerogels exhibit excellent electromagnetic wave absorbing and radar stealth performances.

Boosting Conductive Loss and Magnetic Coupling Based on "Size Modulation Engineering" toward Lower-Frequency Microwave Absorption.

The rational design of absorber size is a promising strategy for obtaining excellent electromagnetic wave (EMW) absorption performance. However, achieving controllable tuning of the material size through simple methods is challenging and the associated EMW attenuation mechanisms are still unclear. In this study, the sizes of metal-organic frameworks (MOFs) are successfully tailored by changing the growth time and the molar ratio of iron (Fe)/organic ligands. The lateral and verticallengths of MOFs vary in the range of 200nm to 2µm and 100nm to 1µm, respectively. Both experiments and simulations confirm that the decrease of MOF size favors the formation of more conductive networks, which is beneficial for improving the conductivity loss. Meanwhile, the micromagnetic simulation reveals that the magnetic coupling can be effectively enhanced by the decrease of MOF size, which is conducive to the improvement of magnetic loss, especially in low-frequency range. The reflection loss of Fe-based MOFs with optimized size reaches -46.4dB at 6.2GHz with an effective absorption bandwidth of 3.1GHz. This work illustrates the important role of size effect in EMW dissipation and provides an effective strategy for enhancing the low-frequency EMW absorption performance.

MOFs-derived Co/C nanoparticle embedded in N, S co-doped graphene for superior electromagnetic wave absorption capacity

Due to their physicochemical properties, the three-dimensional Metal-organic frameworks (MOFs) derived composites show great potential as electromagnetic wave (EMW) absorbers. However, poor impedance matching limits their actual EMW absorption performance. Composite materials that combine magnetic and dielectric losses offer a potential solution to enhance impedance match and significantly improve microwave absorption. In this work, a novel N,S-GS/Co/C composite was fabricated via a solvothermal method and a subsequent pyrolysis process to introducing nitrogen and sulfur co-doped graphene (N,S-GS) into Co-MOF. By co-doping nitrogen and sulfur, abundant defects and disordered sites were introduced on graphene, which stimulate interfacial polarization and dipole polarization. The minimum reflection loss (RL) of the sample obtained by pyrolysis at 600 °C is −68.8 dB at 9.7 GHz. Simultaneously, the thickness is 2.51 mm, and the effective absorption bandwidth (EAB) can reach 3.04 GHz. Its excellent EMW absorption performance is mainly attributed to interfacial polarization, multiple reflections, dipole polarization, magnetic resonance and eddy current loss. Accordingly, the N,S-GS/Co/C composite is convinced to be a competent candidate among EMW absorbers with high absorption intensity.

3D porous NiCo2(CO3)3/reduced graphene oxide aerogel with heterogeneous interfaces for high-efficiency microwave absorption

Advanced electromagnetic absorbing materials (EAMs) with strong absorption and a wide effective absorption bandwidth (EAB), using innovative microstructural design and suitable multicomponents remain a persistent challenge. Here, we report the production of a material by the hydrothermal reduction of a mixture of graphene oxide (GO), Ni(NO3)2·6H2O, and Co(NO3)2·6H2O, resulting in reduced GO (RGO) with a self-assembled 3D mesh structure filled with NiCo2(CO3)3. The unique microstructure of this assembly not only solves the problem of NiCo2(CO3)3 particles agglomerating but also changes the electromagnetic parameters, thereby improving the impedance matching and attenuation ability. High electromagnetic wave absorption (EMA) was achieved by combining the 3D interconnected mesh structure and the various interfaces between NiCo2(CO3)3 and RGO. The minimal reflection loss (RLmin) was −58.5 dB at 2.3 mm, and the EAB was 6.5 GHz. The excellent EMA performance of the aerogel can be attributed to the multiple reflection, scattering, and relaxation process of the porous 3D structure as well as the strong polarization of the interfacial matrix.

Bayberry-like bimetallic CoNi-MOF-74 derivatives/MXene hybrids with abundant heterointerfaces toward high-efficiency electromagnetic wave absorption

The flourishing development of electronic devices and radar detection technologies necessitates the urgent creation of high-efficiency electromagnetic wave (EMW) absorption materials with expansive absorption bandwidths. Although MXene has garnered significant interest in the domain of EMW absorption due to its tunable dielectric properties and structural designability, its high permittivity often results in poor impedance matching and a single loss mechanism, which makes it difficult to realize optimal EMW absorption capabilities. In this work, CoNi bimetallic metal–organic frameworks (MOFs) derived bayberry-like magnetic porous carbon (CoNiMPC)@carbon nanotubes (CNTs)/MXene (CNCM) hybrids were initially synthesized via simple solution precipitation, thermal treatment, and electrostatic self-assembly strategy. As anticipated, excellent EMW absorption characteristics were achieved by adjusting the ratio of CoNiMPC@CNTs and MXene. Multi-heterointerfaces consisting of zero-dimensional porous carbon, one-dimensional carbon nanotubes, and two-dimensional (2D) MXene, electrical/magnetic coupling effects, and polarization loss induced by abundant heterointerfaces endow the prepared CNCM hybrids with high-performance EMW absorption. Notably, the CNCM-7 hybrid material exhibits a minimum reflection loss (RLmin) of − 65.3 dB at 6.8 GHz with a mere 2.7 mm thickness and an effective absorption bandwidth (EAB, RL < −10 dB) of 5.0 GHz at a thickness of 1.27 mm. This study proposes a unique viewpoint and approach towards the design and preparing high-performance MXene-based EMW absorption materials.

Cobalt-nickel carbonate hydroxide composites achieving excellent electromagnetic absorption and wide bandwidth through incorporation with polypyrrole nanotubes

Electromagnetic absorption composite with prominent absorption properties and wider absorption bandwidth are in urgent desire. Polypyrrole-based composite is a prosperous candidate due to its easiness in synthesis, morphological diversity and controllable conductivity. In the present work, cobalt-nickel carbonate hydroxide (CCH) microwave absorption materials incorporating polypyrrole nanotubes (PNTs) in different loadings (CCH/PNTs) were prepared via a facile template method next to a hydrothermal treatment. The CCH is revealed in a sea-urchin-like morphology and PNTs are dispersed on the surface of the CCH. In light of the unique morphology, large specific surface area and interfaces, the CCH/PNTs composites exhibit excellent electromagnetic wave (EMW) absorption performance and extensive bandwidth of absorption. With a 180 mg loading of PNTs, the composite delivers a minimum reflection loss (RLmin) of − 57.4 dB with an effective absorption bandwidth (EAB) of 5.44 GHz. By tuning the matching thickness, a wide EAB larger than 7 GHz can be obtained in the X-band and Ku-band. The prominent EMW absorption properties can be ascribed to the dielectric loss, the polarization loss and multiple scattering attenuation from the large surfaces and interfaces from PNTs, and the optimization of impedance matching via CCH. The present research can offer an intuitive guide for the conception of microwave absorbers with wide absorption bandwidth.

Hydrophobic Composite Foams with Asymmetric Gradient Sandwich Structure for Excellent Electromagnetic Interference Shielding and Photothermal Response.

The evolution of contemporary electronics urgently requires the use of versatile electromagnetic interference (EMI) shielding materials in complex environments. Interlayer polydimethylsiloxane (PDMS)/Fe3O4@multiwalled carbon nanotubes (MWCNTs) foams were prepared by a simple physical foaming method with excellent flexibility and electromagnetic wave absorption. The bottom nickel aramid paper (NiP) layer creates a dense conductive network by chemical plating technology, which ensures excellent EMI effectiveness. The upper carbon black (CB)/Fe3O4 layer further improves the absorption performance via conductive loss and magnetic loss. With the effective layout of the impedance matching layer, absorbing layer, and conductive shielding layer, the CB/Fe3O4-PDMS/Fe3O4@MWCNTs-NiP composite material achieves an EMI shielding effectiveness (EMI SE) of 61.7 dB and an absorption coefficient of 0.58 at X-band. In addition, the composite foam provides photothermal conversion and hydrophobicity due to the effective stacking of PDMS and CB/Fe3O4. Thus, the multifunctional composite foam presents a broad range of possible applications, benefiting EMI shielding as well as other specific areas.

Natural bamboo‐derived NbC nanowires for efficient electromagnetic wave absorption

AbstractTransition metal carbides (TMCs) are a class of materials with excellent dielectric properties and thermal stability, which exhibit enormous potential in high temperature electromagnetic wave absorption (EWA). However, the high dielectric constant and electrical conductivity of TMCs usually cause impedance mismatch, and their high density also prevents further practical applications. To solve these problems, the lightweight and impedance matching NbC nanowires (NbCnws) were prepared by using bamboo powder as a carbon source and subsequent carbothermal reduction reaction process. The as‐synthesized NbCnws all exhibit a low density of 0.23 g/cm3 and superior EMA performance. It is worth noting that the minimum reflection loss (RLmin) of the sample is −43.03 dB at 5.92 GHz and the corresponding matching thickness is only 3.7 mm when sintering temperature is 1500°C. The excellent electromagnetic wave absorption (EWA) performance is attributed to good impedance matching and strong dielectric loss. This research work provides a prospect for the development and utilization of one‐dimensional TMC materials in the field of microwave absorption materials.

Ambient synthesis of one-dimensional core-shell nanocomposites by encapsulating SiC nanowires with layered double hydroxide nanosheets for high-performance microwave absorption application

The optimization design of micro/nanostructure and composition is an effective strategy for preparing high-performance electromagnetic wave absorption (EMA) material. Here, we provide a single-step in-situ electrostatic self-assembly growth approach at room temperature for the efficient construction of core-shell structural composites, consisting of bimetallic layered double hydroxides (LDH) nanosheets tightly wrapped around SiC nanowires. The formation of the bimetallic LDH nanosheets shell is caused by the binding of the bimetallic cations to OH−, which mainly arises from the hydrolysis of water induced by the 2-methylimidazole molecule, while the protonated 2-methylimidazole acts as an interlayer equilibrium anion. Through a heat-treatment process under air, the resulting derivatives of Co, Ni-LMc@SiC, and Zn, Ni-LMc@SiC generate excellent EMA properties due to the intrinsic and synergistic properties of the dielectric/magnetic components and the core-shell structure that provides numerous physical contacts and endows the composite with enhanced interfacial polarization and electron transport. As a result, Zn, Ni-LMc@SiC displays the highest RLmin value of −55.59 dB at 2.8 mm and EABmax of 6.28 at 2.4 mm, while Co, Ni-LMc@SiC has the widest EAB of 6.32 GHz at a thinner thickness of 2.2 mm. The successful construction of core-shell structures for LDH and SiC nanowires in such a facile strategy will broaden the application and development of high-performance EMA materials.

α-PW11Fe(Co/Ni)/BC derived carbon fiber based nanocomposites for high efficiency electromagnetic wave absorption via synergistic effects of polarization and conductance

In order to enhance the wave-absorbing performance of dielectric/carbon fiber based wave-absorbing materials and explore the dissipative mechanism of electromagnetic wave (EMW), this study utilizes liquid diffusion of K4PW11O39Fe(III)(H2O) (α-PW11Fe), K5PW11O39Co(II)(H2O) (α-PW11Co), K5PW11O39Ni(II)(H2O) (α-PW11Ni) and bacterial cellulose (BC), as well as high temperature carbonization strategy to prepare polycrystalline polyphase transition metals and their compounds with three dimensional porous conductive network structure loaded carbon fiber based nanocomposites wave-absorbing materials. By changing the element type, drying mode and filling amount, we can achieve the tunability of electromagnetic parameters and absorbing properties. Impressively, the best synthesized sample 20 %-α-PW11Ni/BC derived carbon fiber based nanocomposites has excellent EMW absorption properties, with a maximum reflection loss (RL) of -68.1 dB at 2.6 mm matching thickness. The effective absorbing bandwidth (EAB) is 7.2 GHz, and the RL less than -10 dB in the frequency band of 2.2–5.0 mm thickness is 5.3 to 18.0 GHz. The excellent absorbing performance is attributed to the synergy of polarization and conductance, balanced impedance matching, good interface/dipole polarization, and multiple reflections and scattering. Therefore, the prepared composite has a broad application prospect in the field of EMW absorption, and provides a new idea for the design of new efficient absorbing materials.

Compressible and conductive multi-scale composite aerogel elastomers for electromagnetic wave absorption, energy harvesting, and piezoresistive sensing

With the rapid development of electronic technology, wearable electronic devices have been widely used in the lives of people. However, integrating multiple functions, such as flexible sensing and electromagnetic protection, into a single device remains challenging. Herein, silver nanowires and cobalt-nickel@carbon were assembled into a conductive and magnetic composite aerogel enhanced by aramid nanofibers and cellulose nanofibrils by freeze-drying. It exhibited an excellent electromagnetic wave absorption ability with an optimal minimum reflection loss of −51.6 dB. Then, polydimethylsiloxane (PDMS) was introduced in the subsequent vacuum-assisted impregnation process to obtain a compressible aerogel elastomer with excellent mechanical and electrical properties. It was not only used as a piezoresistive sensor for different application scenes (e.g., human behavior monitoring, pressure array identification, and parking location recognition) but also as a triboelectric nanogenerator for high-performance energy harvesting. Such a unique and multifunctional composite aerogel elastomer will open up new potential applications for electromagnetic protection, blue energy harvesting, and piezoresistive sensing.