Excellent Low‐Frequency Microwave Absorption and High Thermal Conductivity in Polydimethylsiloxane Composites Endowed by Hydrangea‐Like CoNi@BN Heterostructure Fillers

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(48)

Published: Oct. 9, 2024

Abstract The advancement of thin, lightweight, and high‐power electronic devices has increasingly exacerbated issues related to electromagnetic interference heat accumulation. To address these challenges, a spray‐drying‐sintering process is employed assemble chain‐like CoNi flake boron nitride (BN) into hydrangea‐like CoNi@BN heterostructure fillers. These fillers are then composited with polydimethylsiloxane (PDMS) develop CoNi@BN/PDMS composites, which integrate low‐frequency microwave absorption thermal conductivity. When the volume fraction 44 vol% mass ratio BN 3:1, composites exhibit optimal performance in both achieve minimum reflection loss −49.9 dB effective bandwidth 2.40 GHz (3.92–6.32 GHz) at thickness 4.4 mm, fully covering n79 band (4.4–5.0 for 5G communications. Meanwhile, in‐plane conductivity ( λ ∥ ) 7.31 W m −1 K , ≈11.4 times (0.64 pure PDMS, 32% higher than that (CoNi/BN)/PDMS (5.52 same obtained through direct mixing.

Language: Английский

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Recent progress in carbon-based materials and loss mechanisms for electromagnetic wave absorption

Carbon, Journal Year: 2024, Volume and Issue: 219, P. 118834 - 118834

Published: Jan. 18, 2024

Language: Английский

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Perspective of electromagnetic wave absorbing materials with continuously tunable effective absorption frequency bands

Composites Communications, Journal Year: 2024, Volume and Issue: 50, P. 101993 - 101993

Published: July 9, 2024

Language: Английский

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Achieving Ultra-Broad Microwave Absorption Bandwidth Around Millimeter-Wave Atmospheric Window Through an Intentional Manipulation on Multi-Magnetic Resonance Behavior

Nano-Micro Letters, Journal Year: 2024, Volume and Issue: 16(1)

Published: April 22, 2024

Abstract The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range, posing increasingly severe challenges in terms pollution prevention and radar stealth. However, existing absorbers are still inadequate addressing these issues due to their monotonous magnetic resonance pattern. In this work, rare-earth La 3+ non-magnetic Zr 4+ ions simultaneously incorporated M-type barium ferrite (BaM) intentionally manipulate multi-magnetic behavior. By leveraging contrary impact on magnetocrystalline anisotropy field, restrictive relationship between intensity successfully eliminated. peak-differentiating imitating results confirm that significant phenomenon emerges around 35 GHz reinforced exchange coupling effect Fe 2+ ions. Additionally, Mössbauer spectra analysis, first-principle calculations, least square fitting collectively identify additional doping leads a profound rearrangement occupation thus makes portion polarization/conduction loss increase gradually. As consequence, –Zr co-doped BaM achieves an ultra-broad bandwidth 12.5 + covering from 27.5 40 GHz, which holds remarkable potential for atmospheric window GHz.

Language: Английский

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Mechanisms, design, and fabrication strategies for emerging electromagnetic wave-absorbing materials

Cell Reports Physical Science, Journal Year: 2024, Volume and Issue: 5(7), P. 102097 - 102097

Published: July 1, 2024

The rapid development of intelligent devices imposes new demands on electromagnetic wave (EMW)-absorbing materials, especially concerning wide-spectrum absorption, frequency band manipulation, and multifunctional integration. However, conventional investigations EMW-absorbing materials face several challenges that collectively limit the effectiveness existing amid growing demands, including ambiguous (EM) loss mechanisms, impedance mismatches, deficiencies in integrated design. This review elucidates EM delineates key bridge mechanisms linking microscopic macroscopic factors, proposes dielectric polarization models to clarify mechanisms. Additionally, it delves into unique advantages core-shell structures porous optimization. Finally, introduces fabrication approaches integrate detailing design strategies exploring potential applications. By consolidating these cutting-edge achievements, this aims guide scientific advancement materials.

Language: Английский

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Cross‐Scale Synergistic Manipulation of Dielectric Genes in Polymetallic Sulfides from Micropolarization to Macroconductance Toward Wide‐Band Microwave Absorption

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: May 9, 2024

Abstract Recently, the design and development of efficient microwave absorbents by facile engineering approaches have attracted much attention. Particularly, some unique structures caused cross‐scale are promising in enhancing absorbing capability toward irradiation. Herein, strategy is implemented to enhance electromagnetic wave absorption performance polymetallic sulfides (PMS). In PMS, dipole polarization unit optimized, distribution electronic states improved doping Ti atoms; Meanwhile, MS/M 3 S 4 homogeneous hetero‐phases interfaces constructed PMS using a phase separation strategy; conductivity modulated addition acetylene black (ACET). The synergy leads significant enhancement (MA) PMS/ACET composites. optimal reflection loss value Ti‐LES with 10% ACET reaches −55.49 dB effective bandwidth 6.73 GHz. 17.5% ACET‐conditioned Ti‐HES achieves −37.2 at low frequency 4.8 This study not only provides novel for new broadband MA materials but also validates idea multi‐scale synergistic optimization materials.

Language: Английский

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A Perspective of Tailoring Dielectric Genes for 2D Materials Toward Advanced Electromagnetic Functions

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(52)

Published: Aug. 27, 2024

Abstract 2D materials and their composites with electromagnetic properties are becoming increasingly popular. Obtaining insight into the nature of (EM) response manipulation is imperative to guide scientific research technological exploitation at such a critical time. From this perspective, dielectric genes material hybrids have been highlighted based on recent literature. This endows an unlimited possibility manipulating EM response, even elevated temperatures. The definitions criteria toward systematically clarified summarized. gene categories successfully discriminated, including conduction networks, intrinsic defects, impurity interfaces in composite, temperature evolution revealed detail. More importantly, tuning strategies for microwave absorption, shielding effectiveness, expanded functions thoroughly discussed. Finally, significant predictions provided multispectral functions, future applications multifunctional exploration anticipated. Dielectric will open unexpected horizon advanced functional coming 5G/6G age, providing boost promoting environmental protection, devices, next‐generation smart devices.

Language: Английский

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Miniaturized Hard Carbon Nanofiber Aerogels: From Multiscale Electromagnetic Response Manipulation to Integrated Multifunctional Absorbers

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(48)

Published: July 17, 2024

Abstract The multiscale structural engineering strategy presents a powerful method for tailoring the attributes of materials at various levels, enabling flexible control and manipulation their electromagnetic properties. Nonetheless, orchestrating architecture polymer‐derived carbon aerogels specifically microwave absorption poses significant challenges. Herein, aramid‐derived hard nanofiber aerogel microspheres (CNFAMs) featuring hierarchical skin‐core structure are fabricated through wet‐spinning technique, combined with reprotonation‐mediated self‐assembly carbonization processes. presence large‐scale voids between neighboring microscale porosity within themselves improves impedance matching promotes reflection scattering. distinct graphitic domains defects serve as pivotal elements conduction polarization losses, significantly impacting attenuation. By meticulously macroscale dimensions, porous architecture, nanoscale domains, optimized CNFAMs demonstrate remarkable bandwidth 9.62 GHz an ultralow filling 0.97 wt%. Additionally, implementation application‐oriented innovative integration polysilsesquioxane‐CNFAMs in host–guest is explored. This composite system brings together broadband absorption, superhydrophobicity, thermal insulation, resistance to freezing, robust tolerance harsh environments. Such multifaceted approach designed tackle growing challenges associated complex environments effectively.

Language: Английский

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MXene‐Based Ultrathin Electromagnetic Wave Absorber with Hydrophobicity, Anticorrosion, and Quantitively Classified Electrical Losses by Intercalation Growth Nucleation Engineering

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(37)

Published: March 22, 2024

Abstract MXene, a highly regarded material, has garnered significant attention within the electromagnetic wave (EMW) absorption field. However, practical application of MXene is limited in harsh environments. Herein, magic technique strategy intercalation growth nucleation engineering employed to prepare multifunctional MXene‐based EMW materials. By regularly introducing different metal ions between layers an ultrathin absorber can be achieved by annealing after reacting specific positions. The synthesized MCFC‐69‐8 shows hydrophobicity properties and exhibits large charge‐transfer resistance 18112 Ω cm 2 with low corrosion rate rate, indicating good anti‐corrosion property. Through applying series mathematical methods, 25% relaxation polarization loss 75% conduction loss, its time linked type resulting effective bandwidth (EAB) 4.9 GHz ultra‐thin optimal matching thickness 1.48 mm. Finally, built using CST attain ultrabroad EAB covering 2–18 GHz. This not only simplifies process but also achieves high‐performance absorber, providing valuable perception for realizing thinner absorbers future.

Language: Английский

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Enhanced electromagnetic wave absorption and mechanical performances of graphite nanosheet/PVDF foams via ice dissolution and normal pressure drying

Journal of Materials Chemistry C, Journal Year: 2024, Volume and Issue: 12(21), P. 7775 - 7783

Published: Jan. 1, 2024

An ice dissolution-normal pressure drying strategy based on graphite nanosheet was proposed to prepare porous PVDF foams, which own exceptional microwave absorption (RL max = −57.68 dB, EAB 6.86 GHz) and compression strength (300.9 kPa).

Language: Английский

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