A Review on Graphene‐Based Electromagnetic Functional Materials: Electromagnetic Wave Shielding and Absorption

Advanced Functional Materials, Год журнала: 2022, Номер 32(42)

Опубликована: Июль 1, 2022

Abstract Electromagnetic (EM) functional materials play an increasingly important role in solving EM wave pollution both modern military and civil fields. Graphene‐based are the most promising candidates applications of shielding absorption owing to their remarkable structures enhanced properties. Designing graphene‐based with elaborately controlled microstructures optimized properties can effectively improve energy attenuation conversion. Herein, study begins mechanism, multiscale design strategies outlined, including molecular‐scale, micro/nanoscale structure, macroscale integration assembly strategies. Applications fields reviewed, focusing on latest advances assemblies such as films, fabrics, composites. Finally, current challenges future directions this fast‐growing field predicted.

Язык: Английский

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Structural Defects in Phase‐Regulated High‐Entropy Oxides toward Superior Microwave Absorption Properties

Advanced Functional Materials, Год журнала: 2022, Номер 33(1)

Опубликована: Окт. 27, 2022

Abstract High‐entropy (HE) oxides have become increasingly popular as electromagnetic wave‐absorbing materials owing to their customizable structure and unique HE effects. However, the weak loss property of single‐phase ceramics approaches implemented improve them based on semi‐empirical rules severely limit development. Herein, two biphasic are prepared by simple sintering realize accurate regulation crystal phases structural defects. It is verified that effects cause various defects beneficial for microwave dissipation within complex‐phase ceramics. In spinel/perovskite oxides, around interface spinel (111) perovskite (110) planes, notable stress concentrations lattice distortions directly observed, inducing numerous point stacking faults. Interestingly, besides existing heterogeneous rock salt (220)/spinel (220) plane defects, salt/spinel enabled synergistic via precise components’ phase. Driven multi‐phases in complexes, intense polarization evidently found, confirmed first‐principles calculations. Accordingly, demonstrate excellent absorption performance, minimal reflection −54.5 dB achieved. Therefore, this study provides valuable guidelines design absorbers using oxides.

Язык: Английский

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Ultrabroad Microwave Absorption Ability and Infrared Stealth Property of Nano-Micro CuS@rGO Lightweight Aerogels

Nano-Micro Letters, Год журнала: 2022, Номер 14(1)

Опубликована: Авг. 20, 2022

Developing ultrabroad radar-infrared compatible stealth materials has turned into a research hotspot, which is still problem to be solved. Herein, the copper sulfide wrapped by reduced graphene oxide obtain three-dimensional (3D) porous network composite aerogels (CuS@rGO) were synthesized via thermal reduction ways (hydrothermal, ascorbic acid reduction) and freeze-drying strategy. It was discovered that phase components (rGO CuS phases) micro/nano structure (microporous nanosheet) well-modified modulating additive amounts of changing ways, resulted in variation pore structure, defects, complex permittivity, microwave absorption, radar cross section (RCS) value infrared (IR) emissivity. Notably, obtained CuS@rGO with single dielectric loss type can achieve an bandwidth 8.44 GHz at 2.8 mm low filler content 6 wt% hydrothermal method. Besides, aerogel realizes minimum reflection (RLmin) - 60.3 dB lower 2 wt%. The RCS reach 53.3 m2, effectively reduces probability target being detected detector. Furthermore, laminated architecture multicomponent endowed insulation IR versatility. Thus, this work offers facile method design develop rGO-based absorbers radar-IR stealth.

Язык: Английский

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Fabrication of core-shell structure NiFe2O4@SiO2 decorated nitrogen-doped graphene composite aerogels towards excellent electromagnetic absorption in the Ku band

Carbon, Год журнала: 2023, Номер 210, С. 118047 - 118047

Опубликована: Апрель 21, 2023

Язык: Английский

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Construction of multi-dimensional NiCo/C/CNT/rGO aerogel by MOF derivative for efficient microwave absorption

Carbon, Год журнала: 2023, Номер 205, С. 411 - 421

Опубликована: Янв. 30, 2023

Язык: Английский

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Catfish Effect Induced by Anion Sequential Doping for Microwave Absorption

Advanced Functional Materials, Год журнала: 2022, Номер 33(8)

Опубликована: Дек. 8, 2022

Abstract Heteroatom doping engineering is desirable in tuning crystal structures and electrical properties, which considered an opportunity to further develop microwave absorption materials. However, the competition mechanism priority among doped atoms have not been revealed, are insufficient guide most reasonable dielectric coupling model design high‐performance absorbers. In this work, based on situ N O, ex S introduced through external thermal driving, leading fierce anions. Specifically, replace pyrrole N, drive out lattice create O vacancies, bringing more extensive local charge redistribution stronger electron interaction, thus activating defect‐induced polarization (3–6 times higher than conduction loss) middle/high‐frequency region. Therefore, effective bandwidth (EAB) of 9.03 GHz minimum reflection loss ( RL min ) −64.05 dB at a filling rate 10 wt.% obtained, improves record carbon absorbers as reported. Through macro‐designs, i.e., multi‐layer gradient metamaterial, or utilizing other advantages, e.g., cost‐effective, stable chemical properties wide‐angle absorption, porous may possess great application prospect naval field.

Язык: Английский

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Metal-organic frameworks with fine-tuned interlayer spacing for microwave absorption

Science Advances, Год журнала: 2024, Номер 10(11)

Опубликована: Март 13, 2024

Designing a functional, conductive metal-organic framework (cMOF) is highly desired. Substantial efforts have been dedicated to increasing the intralayer conjugation of cMOFs, while less dedication has made tuning interlayer charge transport nanosheets for controllable dielectric property. Here, we construct series bimetallic organic frameworks (Zn x Cu 3-x ) (hexahydroxytriphenylene) 2 (ZnCu-HHTP) allow fine-tuned spacing two-dimensional frameworks, by adjusting ratios Zn and metal ions. This approach atomistic design allows finely control transport, band structure, properties cMOF. As result, Zn3Cu1-HHTP, with an optimal property, exhibits high-efficiency absorption in gigahertz microwave range, achieving ultra-strong reflection loss −81.62 decibels. study not only advances understanding microstructure-function relationships cMOFs but also offers generic nanotechnology–based MOFs targeted applications.

Язык: Английский

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Boosting Interfacial Polarization Through Heterointerface Engineering in MXene/Graphene Intercalated-Based Microspheres for Electromagnetic Wave Absorption

Nano-Micro Letters, Год журнала: 2023, Номер 15(1)

Опубликована: Июнь 7, 2023

Multi-layer 2D material assemblies provide a great number of interfaces beneficial for electromagnetic wave absorption. However, avoiding agglomeration and achieving layer-by-layer ordered intercalation remain challenging. Here, 3D reduced graphene oxide (rGO)/MXene/TiO2/Fe2C lightweight porous microspheres with periodical intercalated structures pronounced interfacial effects were constructed by spray-freeze-drying microwave irradiation based on the Maxwell-Wagner effect. Such approach reinforced via defects introduction, skeleton, multi-layer assembly multi-component system, leading to synergistic loss mechanisms. The abundant 2D/2D/0D/0D heterojunctions in high density polarization charges while generating sites, resulting boosted polarization, which is verified CST Microwave Studio simulations. By precisely tuning nanosheets heterostructures, both impedance matching improve significantly. At low filler loading 5 wt%, rate exceeds 70%, minimum reflection (RLmin) -67.4 dB can be achieved. Moreover, radar cross-section simulations further confirm attenuation ability optimized microspheres. These results not only novel insights into understanding enhancing effects, but also constitute an attractive platform implementing heterointerface engineering customized hierarchical architectures.

Язык: Английский

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Recent advances in graphene aerogels as absorption-dominated electromagnetic interference shielding materials

Carbon, Год журнала: 2023, Номер 205, С. 112 - 137

Опубликована: Янв. 17, 2023

Язык: Английский

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

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Апрель 17, 2024

Abstract Improving the absorption of electromagnetic waves at low-frequency bands (2-8 GHz) is crucial for increasing (EM) pollution brought about by innovation fifth generation (5G) communication technology. However, poor impedance matching and intrinsic attenuation material in hinders development wave absorbing (EMWA) materials. Here we propose an interface-induced dual-pinning mechanism establish a magnetoelectric bias interface constructing bilayer core-shell structures NiFe 2 O 4 (NFO)@BiFeO 3 (BFO)@polypyrrole (PPy). Such heterogeneous could induce distinct magnetic pinning moment ferromagnetic NFO dielectric dipole rotation PPy. The establishment effect resulted optimized enhanced bands, leading to better EMWA performance. minimum reflection loss (RL min ) thickness 4.43 mm reaches -65.30 dB (the optimal efficiency 99.99997%), effective bandwidth (EAB) can almost cover C-band (4.72 ~ 7.04 with low filling 15.0 wt.%. This work proposes optimize (EMW) pave avenue research high-performance absorbers.

Язык: Английский

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