N, O‐Doped Walnut‐Like Porous Carbon Composite Microspheres Loaded with Fe/Co Nanoparticles for Adjustable Electromagnetic Wave Absorption

Small, Journal Year: 2024, Volume and Issue: 20(20)

Published: Jan. 11, 2024

Abstract This study addresses the challenge of designing simple and environmentally friendly methods for preparation effective electromagnetic wave (EMW) absorbing materials with tailored microstructures multi‐component regulation. N, O doped walnut‐like porous carbon composite microspheres loaded FeCo nanoparticles (WPCM/Fe–Co) are synthesized through high‐temperature carbonization combined soap‐free emulsion polymerization hydrothermal methods, avoiding use toxic solvents complex conditions. The incorporation magnetic components enhances loss, complementing dielectric loss to optimize EMW attenuation. unique morphology further improves impedance matching. proportions Fe Co can be adjusted regulate material's reflection thickness, bandwidth, allowing fine‐tuning absorption performance. At a low filling ratio (16.7%), optimal WPCM/Fe–Co composites exhibit minimum ( RL min ) −48.34 dB (10.33 GHz, 3.0 mm) an overall bandwidth (EAB) covering entire C bands, X Ku bands. work introduces novel approach composition regulation presents green synthesis method absorbers high‐performance at loading.

Language: Английский

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Hierarchical Assembly of Ternary MOF‐Derived Sandwich Composites for High‐Efficiency Tunable Electromagnetic Wave Absorption

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 31, 2024

Abstract The proliferation of electronic devices drives the adoption electromagnetic wave (EMW) absorbing materials to mitigate pollution. Metal‐organic frameworks (MOFs) reveal great potential in EMW absorption field due their unique pore structure and outstanding physicochemical properties. However, single MOFs are difficult achieve both efficient wide frequency coverage owing limited properties structural composition. Herein, a sandwich‐like ternary MOF composite is successfully synthesized through hierarchical assembly strategy. Following high‐temperature treatment, converted into nitrogen‐doped porous carbon with magnetic metals, non‐magnetic metal oxides, nanotubes on surface (labeled as TiO 2 /C@Co/N/C@CNT). sandwich resulting derivatives provides multi‐level microstructure multi‐component synergistic effects, significantly enhancing capabilities broadening effective bandwidth (EAB). At 1.8 mm matching thicknesses, material achieves reflection loss −56.3 dB 6.6 GHz EAB. Adjusting thicknesses 2.3 3.1 extends EAB 6.1–18 GHz, peaks −47.6 −47.1 dB. This work offers novel guidance for constructing advanced MOF‐derived ultra‐broadband strong meticulous design multiple components combination.

Language: Английский

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Hetero‐Interface Engineering on 9.0 wt% CoO_x‐Doped CeO₂ Nanorods as Electromagnetic Wave Absorber and Integrated into Multifunctional Aerogel

Small, Journal Year: 2024, Volume and Issue: 20(32)

Published: March 14, 2024

Abstract Ceria (CeO 2 ) becomes a promising candidate as electromagnetic wave absorbing materials (EWAMs) for their abundant natural source, rich oxygen vacancy, charge conversion, and electron transfer abilities. However, it remains challenging to regulate its nanoscale atom‐scale composition optimize the performance develop high‐performance commercial devices. Herein, facile method large‐scale synthesis CeO @Co‐x% (x = 5, 7, 9, 11, 13) series EWAMs with diverse amounts of decorated CoO x is presented. By modulating ratio doped , rational hetero‐interface created in @Co‐9% enhance exchange resonances, improving magnetic loss capability optimizing impedance matching. Doped promotes accumulation, interfacial polarization, multiple scattering strengthening EW absorption attenuation, which display superb minimum reflective ( RL min −74.4 dB wide effective bandwidth (EAB) 5.26 GHz. Furthermore, dual crosslinking strategy employed fabricate into an aerogel device integrated lightweight, heat insulation, compression resistance, fame‐retardant functions. This work presents excellent example fast ‐based multiplication 3D

Language: Английский

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Construction of 1D heterogeneous PPy@FeCo@PPy nanotubes with broadband and strong electromagnetic wave absorption

Journal of Alloys and Compounds, Journal Year: 2024, Volume and Issue: 1001, P. 175030 - 175030

Published: May 29, 2024

Language: Английский

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Constructing of three-dimensional molybdenum carbide nanoparticles embedded in honeycomb carbon as efficient microwave absorbers

Journal of Alloys and Compounds, Journal Year: 2024, Volume and Issue: 1004, P. 175732 - 175732

Published: July 27, 2024

Language: Английский

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Heterogeneous three-dimensional FeSiAl@SiO₂@MoS₂ composite with a SiO₂ wave-transmitting layer for enhanced electromagnetic wave absorption performance

Journal of Materials Chemistry A, Journal Year: 2024, Volume and Issue: 12(37), P. 25322 - 25333

Published: Jan. 1, 2024

The incorporation of wave-transparent SiO 2 layer expands the incidence area for EMWs, which significantly enhances electromagnetic wave absorption performance FeSiAl@SiO @MoS .

Language: Английский

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Optimizing dielectric polarization for electromagnetic wave attenuation via an enhanced Maxwell–Wagner–Sillars effect in hollow carbon microspheres

Journal of Materials Chemistry A, Journal Year: 2023, Volume and Issue: 11(43), P. 23498 - 23510

Published: Jan. 1, 2023

The prepared Ni/Ni 2 P/CNs composites with enriched heterojunctions show excellent electromagnetic wave-absorption performances, which exceed most of the previously reported absorbers a hollow structure.

Language: Английский

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Phase Engineering in a Twin‐Phase β/γ‐MoC_x Lightweight Nanoflower with Matched Fermi Level for Enhancing Electron Transport Across the Polarized Interfaces in Electromagnetic Wave Attenuation

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

Published: Sept. 19, 2024

Abstract The phase engineering of the polarization interface is great significance in modifying dielectric loss electromagnetic wave (EMW) attenuation process, but hard to conduct a complex hybrid system. Herein, twin‐phase β/γ‐MoC x @CN with matched Fermi level and closed work function properties lightweight MoC nanoflower constructed, facilitating electron transport withdraw enhanced conductivity polarization. Moreover, EMW multiple dissipations among promoted, displaying better impedance. It delivered remarkable minimum reflection (RL min ) −74.2 dB at thickness 1.5 mm, which far beyond single phased β‐MoC @CN, γ‐MoC reported ‐based absorbers. radar cross‐section (RCS) map simulated, showing brilliant maximum reduction value 13.6 m 2 theta angle 30°. This presented an excellent sample atomic‐level manipulation interfacial absorption materials.

Language: Английский

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Defect engineering of anchored on F-doped BNNR surface to enhance low-frequency microwave absorption and achieve exceptional thermal conductivity properties

Vacuum, Journal Year: 2024, Volume and Issue: 231, P. 113826 - 113826

Published: Nov. 10, 2024

Language: Английский

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Heterogeneous nanospheres comprising FeCo core encapsulated in double-shelled carbon for high-efficiency electromagnetic wave absorption

Journal of Materials Science Materials in Electronics, Journal Year: 2025, Volume and Issue: 36(1)

Published: Jan. 1, 2025

Language: Английский

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