ACS Applied Nano Materials
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2025
·
IF 5.5
Qingkun Xu,Xiaofen Li,Hantao He,Shuixiu Luo,Yi Yu,Zuzhou Xiong,Jujun Yuan,Xianke Zhang,Xiaoqing Liu,Xiurong Zhu
Utilizing the multiple magnetic resonance properties of polymetallic alloys and considering the high electrical conductivity, porous structure, and high specific surface area of traditional phenolic-aldehyde-based carbon aerogels (CAs), ternary FeCoNi alloy nanoparticle-doped CAs (FeCoNi-CAs) with impressive core–shell structure were prepared via a simplified sol–gel method using 1,2-epoxypropane as a catalyst. The composition, conductivity, morphology, textural characteristics, electromagnetic wave absorption (EMA) properties and mechanisms, and radar cross-section (RCS) values of FeCoNi-CAs were first investigated in detail by adjusting the molar ratio of Fe, Co, and Ni elements. The results revealed that the optimum EMA properties occur at the molar ratio of Fe/Co/Ni = 4:1:5, and its corresponding Fe4Co1Ni5-CAs have a maximum effective absorption bandwidth (EABmax) of 6.21 GHz (10.43–16.64 GHz) at a matching thickness of only 1.91 mm. Meanwhile, it possesses a minimum reflection loss (RLmin) of −54.9 dB and an EAB of 5.61 GHz (11.11–16.72 GHz) at the same matching thickness of only 1.87 mm in the medium- and high-frequency regions. The Fe4Co1Ni5-CAs also show the EABmax of 2.38 GHz (matching thickness: only 3.4 mm, 5.59–7.97 GHz) in the low-frequency region. Further analysis demonstrates that the excellent EMA performance of Fe4Co1Ni5-CAs is mainly ascribed to its higher conductivity stemming from its unique Fe/Co/Ni ratio. Not only does this ratio promote the dielectric loss, but simultaneously, it heightens the magnetic loss. This, in turn, intensifies the combined influence of both dielectric and magnetic losses, giving rise to excellent impedance matching properties. This study could offer a catalyst and a more feasible way to synthesize polymetallic nanoparticle-doped CAs featuring diverse microstructures and superior EMA characteristics.
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2025
·
IF 5.5
Xiao Wang,Yuxin Jin,Hongguo Zhang,Qiong Wu
Ion-intercalated MoS2 can enhance its electrochemical activity, electrical conductivity, and stability, which can be combined with other materials to meet specific application requirements, such as the fields of electrochemistry and microwave absorption. This study explored the modulation of electromagnetic characteristics of ion-intercalated MoS2-based ternary FeCoNi alloy nanocomposites, in which MoS2 provides more contact sites for an electromagnetic wave, and the heterogeneous interfaces formed by the heterogeneous structure can improve the stronger interface polarization to enhance the dielectric loss. In addition, by inserting nano-FeCoNi alloy particles into the interlayers of MoS2, the FeCoNi alloy also enhanced the magnetic loss capabilities, in which the impedance matching of FeCoNi/MoS2 composites was also regulated. The results show that the FeCoNi/MoS2 composite achieved a minimum RL (RLmin) value of −54.73 dB at 4.20 GHz with a matching thickness of 3.29 mm, and the effective absorption bandwidth (EAB) was 4.72 GHz at a thickness of 1.32 mm. In addition, the radar cross section (RCS) and COMSOL simulation results verify the possibility of application. The study revealed the microwave loss mechanisms of the FeCoNi/MoS2 heterostructured composites, providing insights for designing novel low-frequency absorbing materials.
研究领域:
材料科学
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电磁学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 18
·期 1
·113
·
IF 3.1
Yifan Fei,Junya Yao,Wei Cheng,Wenling Jiao
Microwave absorbers with infrared camouflage are highly desirable in military fields. Self-supporting 3D architectures with tailorable shapes, composed of FeCoNi alloy/carbon nanotubes (CNTs) @ carbon nanofibers (CNFs), were fabricated in this study. On the one hand, multiple loss mechanisms were introduced into the high-elastic sponges. Controllable space conductive networks caused by the in situ growth of CNTs on the CNFs contributed to the effective dielectric and resistance loss. Moreover, the uniformly distributed magnetic alloy nanoparticles (NPs) with dense magnetic coupling resulted in magnetic loss. On the other hand, heterogeneous interfaces were constructed by multicomponent engineering, causing interfacial polarization and polarization loss. Furthermore, the internal structures of sponges were optimized by regulating the alloy NPs sizes and the growth state of CNTs, then tuning the impedance matching and microwave absorption. Therefore, the high-elastic sponges with ultra-low density (7.6 mg·cm−3) were found to have excellent radar and infrared-compatible stealth properties, displaying a minimum refection loss (RLmin) of −50.5 dB and a maximum effective absorption bandwidth (EABmax) of 5.36 GHz. Moreover, the radar stealth effect of the sponges was evaluated by radar cross-section (RCS) simulation, revealing that the multifunctional sponges have a promising prospect in military applications.
研究领域:
材料科学
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电磁学
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军事应用
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Yuning Su,Xuewei Ding,Jiongliang Yuan
Fe-based catalysts have a good prospect in oxygen reduction reaction (ORR) in fuel cells. However, the catalytic activity of Fe-based catalysts requires further improvement to satisfy the demand in industrial application and the working mechanism is still shrouded in ambiguity. Here, a ferromagnetic catalyst with nitrogen-doped carbon supported FeCoNi alloy was synthesized by impregnation-pyrolysis method. The micromorphology and structure of the catalyst was analyzed by XRD , SEM, TEM, XPS, BET and Raman spectroscopy . The trimetallic catalyst showed high ORR activity in 0.1 M KOH with a half-wave potential of 0.908 V and a limiting current density of 6.153 mA cm −2 , which was superior to 20 % Pt/C. The synergistic effect of FeCoNi alloy regulated the spin polarization and the regulated spin state improved ORR performance by facilitating the adsorption of O 2 molecules and the conversion of the activated intermediates.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
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IF 8.2
Hongrui Huang,Qianqian Liang,Guangchao Li,Huajun Guo,Zhixing Wang,Guochun Yan,Xinhai Li,Hui Duan,Jiexi Wang
Rechargeable Zn–air batteries (RZABs) are poised for industrial application, yet they require low-cost, high-performance catalysts that efficiently facilitate both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). The pivotal challenge lies in designing multimetal active sites and optimizing the carbon skeleton structure to modulate catalyst activity. In this study, we introduce a novel hierarchical porous carbon-supported FeCoNi bifunctional catalyst, synthesized via a spray combustion method. The carbon, derived from sucrose, was tailored into a hierarchical porous morphology through etching with NO3– ions and NaCl, thereby significantly increasing the surface area for the interaction of the O2 and electrolyte interaction. The in situ formation of FeCoNi alloy nanoparticles ensures their uniform dispersion and anchoring, facilitating electron transport. The strong interaction and charge transfer at the heterogeneous FeCoNi alloy interfaces, along with nitrogen doping, which enhances the OER/ORR activity, endow the FeCoNi/N-PC catalyst with exceptional bifunctional catalytic properties, characterized by an activity parameter of 0.73 V. Furthermore, the RZAB assembled with this catalyst demonstrates outstanding cycling stability and reversibility, with a minimal round-trip efficiency decay of 7.6% over 1380 cycles (460 h) at 10 mA cm–2.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Zhe Wang,Jiaming Ang,Bowei Zhang,Youfang Zhang,Xiu Yun Daphne Ma,Tao Yan,Jian Liu,Boyang Che,Yizhong Huang,Xuehong Lu
The rational design and exploration of highly efficient, low-cost, and robust electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical for development of rechargeable metal-air batteries. Herein, we report a novel approach for the synthesis of bifunctional electrocatalysts, where Fe 0.5 Co 0.5 and Fe 0.5 Co 0.4 Ni 0.1 alloys are encapsulated in the nitrogen-doped carbon nanotubes-grafted porous polyhedron-derived hybrid fibers (FeCo/FeCoNi@NCNTs-HF). Benefiting from its hierarchically porous structure and strong synergetic coupling among FeCo, FeCoNi alloys, and N-doped carbon species. The obtained electrocatalyst exhibits a positive half-wave potential of 0.850 V for ORR and a low potential of 1.608 V to achieve a current density of 10 mA cm −2 for OER, as well as superior stability in alkaline media. As a demonstration, FeCo/FeCoNi@NCNTs-HF is employed as the electrocatalysts in the air cathode of a Zn-air battery, which shows superior discharge and charge performance, large power density, high specific capacity, and outstanding cycling stability of 240 h (360 cycles). More impressively, excellent cyclabilitiy with a lifetime of 670 h (1005 cycles) is also achieved by the Zn-air battery with FeCo/FeCoNi@NCNTs-HF as the self-supported air electrode. This work will open a novel avenue to develop advanced bifunctional electrocatalysts for the next generation of metal-air batteries.
研究领域:
材料科学
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电化学
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能源存储与转换
✓ 已验证
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2025
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IF 5.1
Yingying Zhou,Chenyu Zhu,Haonan Du,Jinlei Wu,Chaoqun Yang,Shanshan Xiao,Wen Zheng,Rui Xin,Yikun Yang,Enyuan Zhen,Zhaowen Ren,Hui Xie
Magneto-carbon composites are promising materials for mitigating electromagnetic pollution due to combined dielectric and magnetic loss mechanisms. However, such absorbers often have unsatisfactory wave-absorbing properties due to the difficulty in matching the magnetic permeability with the dielectric properties. The multilayered hollow carbon cubes anchored to a ternary FeCoNi alloy were fabricated using a self-tempered engineering strategy. The multilayer structures are formed in two steps and have an iron cobalt-nickel alloy core encapsulated in a hollow cubic carbon shell. Initially, a phenolic resin (PR)-coated FeCoNi-Prussian blue analogue (PBA) was prepared, followed by high-temperature vacuum pyrolysis. The inner carbon layer, derived from PBA, exhibits high crystallinity, while the outer PR-derived carbon layer is amorphous, preventing agglomeration of the carbonized FeCoNi alloy particles. The amorphous outer layer enables electromagnetic waves to be better absorbed and consumed within the absorber due to its ability to effectively modulate conductivity and impedance matching. By leveraging heterogeneous interface polarization and modulating electrical conductivity through control of graphite crystallinity, a minimum reflection loss (RL min ) of −74.2 dB and an effective absorption bandwidth (EAB) of 5.8 GHz across the 2–18 GHz range were achieved. The study provides an effective approach to broaden the application prospects of advanced magneto-carbon composite absorbers by using a multilayer structure to achieve a balance between magnetic loss and dielectric properties.
研究领域:
材料科学
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电磁学
·
纳米技术
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复合材料
✓ 已验证
产品关联
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2025
·Vol. 8
·期 6
·455
·
IF 21.8
Guo Rui,Li Shutong,Duan RongXia,Sun Yunjun,Li Jianhui,Wu Yanzhao,Wang Lianjun,Jiang Wan
Overcoming the challenge of decoupling impedance matching from attenuation for low-frequency (2–10 GHz) electromagnetic wave absorption, this work presents a defect-engineered multiphase medium-entropy sulfide composite. Synthesized via integrated mechanical alloying and surfactant-assisted hydrothermal sulfidation, the composite integrates sulfur vacancy-rich (Fe,Co,Ni) 9 S 8 , anisotropic FeCoNi alloy, CoFe₂O₄, and porous MoS 2 . This architecture creates abundant heterogeneous interfaces and interfacial sulfur vacancies, significantly enhancing defect-induced polarization and dielectric loss via the “Janus effect.” Concurrently, the magnetic components boost magnetic loss while optimizing impedance matching. Benefiting from this magneto-dielectric synergy, the composite achieves exceptional absorption: a minimum reflection loss ( RL min ) of -50.4 dB at 3.96 GHz and a remarkable RL min -77.5 dB at 9 GHz. Radar cross-section simulations confirm application potential. This work provides strategic insights for designing innovative low-/mid-frequency absorbers through synergistic dielectric-magnetic loss in polymetallic sulfide heterostructures.
研究领域:
材料科学
·
电磁功能材料
·
纳米复合材料
·
介电与磁性材料
·
能量转换与吸收
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）