Materials Horizons
·
2024
·
IF 12.2
Geng Chen,Tao Zhang,Limin Zhang,Kai Tao,Qiang Chen,Hongjing Wu
Interface engineering, by modulating defect distribution and impedance at interfaces and inducing interfacial polarization, has proven to be an effective strategy for optimizing dielectric properties. However, the inherent incompatibility between heterogeneous phases presents a significant challenge in constructing multi-heterointerfaces and understanding how their distribution influences dielectric performance. Herein, we constructed an EGaIn@Ni/NiO/Ga2O3 composite structure by employing a low-intensity ultrasound-assisted galvanic replacement reaction followed by high-temperature annealing. The controlled addition of Ni salts allowed for the fine-tuning of Ni, NiO, and In concentrations and their spatial distribution within the interfacial architecture. Annealing treatment induced a transition from amorphous to crystalline phases, triggering dual relaxation behaviors between EGaIn/Ni and NiO/Ga2O3. Additionally, significant charge accumulation was observed at the NiO/Ga2O3 interface, likely due to the substantial work function difference between Ni and NiO, coupled with the low barrier height between EGaIn and Ni, which facilitates electron migration. Consequently, the optimized samples exhibited a maximum absorption bandwidth of 7.92 GHz, which is the highest among the EGaIn-based absorbers reported in the literature. This work not only elucidates the mechanism by which multi-heterogeneous interfacial distributions regulate the dielectric properties but also provides an effective approach for modulating the electromagnetic wave performance of liquid metals.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 36
·
IF 1.768
Hengnong Li,Chongbo Liu,Bing Dai,Xinghua Tang,Z. John Zhang,Zhiqiang Xiong,Xiaoming Liu
Four chiral poly Schiff bases were synthesized via polycondensation between l- lysine and p-benzoquinone, 1,4-naphthoquinone, dibenzoyl, and 2,3-butanedione, respectively. Subsequently, the silver coordination polymers of the chiral poly Schiff base were prepared upon silver ions coordinating with the chiral poly Schiff bases. The structures of the polymers were characterized with IR, UV-vis, GPC, elemental analysis, and optical activity analysis. The properties of polymers were studied through conductivity testing and electromagnetic parameter testing. The results show that they own good electrical conductvities, and the electrical conductivity of chiral poly-( l- lysine(2,3-butanedione)) Schiff base silver complex can reach 3.7 × 10 2 S/cm. The electromagnetic wave absorption properties of four silver complexes were calculated using transmission line theory, the maximum reflection loss of chiral poly-( l- lysine(p-benzoquinone)) Schiff base silver complex can reach −45.9 dB at a thickness of 5 mm, while that of achiral poly-( dl -lysine(p-benzoquinone)) Schiff base silver complex is −20.1 dB at a thickness of 5 mm. The enhanced microwave absorbing properties were attributed to the chiral feature. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42498.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lan Long,Yuting Zhang,Henghai Zhu,Yang Li,Wei Zhou
Reliability and stability of electromagnetic wave absorption (EMA) materials used in high-temperature fields such as aircraft and aero-engines are of great interest. In this regard, the C f /mullite composites with an opportune heterogeneous interface were fabricated using gel-casting and pressureless sintering techniques. The as-prepared composites exhibited excellent EMA performance with multiple relaxation behavior upon increasing testing temperature ranging from 25 °C to 800 °C (the minimum reflection loss (RL min ) of −62.67 dB with a thin thickness of 2 mm at 600 °C). The results demonstrated that the temperature-dependence complex permittivity with multiple relaxation characteristics plays a key role for the EMA performance evolution. The newly generated Cole-Cole semicircle and κ curves with an increasing number of intersections at zero values suggest that the polarization relaxation is enhanced with rising temperatures, thus improving the EMA capacity . It is believed that the C f /mullite composite could be a new promising EMA material at high temperatures.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Xueheng Zhuang,Guoguo Tan,Mingqiang Ning,Chaoyong Qi,Xianjin Ge,Zhen Yang,Qikui Man
Magnetic-loss type electromagnetic wave (EMW) absorbing materials have been always focused on EMW absorbing field due to their excellent magnetic loss properties. However, the impedance mismatching issue still restrict the utilization for those materials. In this work, Ce 2 Fe 17 N 3-δ was synthesized and further coated by silica (Ce 2 Fe 17 N 3-δ @SiO 2 ) for optimizing impedance matching and EMW absorbing performance. The reflection loss (RL) value of Ce 2 Fe 17 N 3-δ @SiO 2 absorber is ~−63.5 dB at 7.86 GHz with thickness of 1.96 mm under 30 vol% loading. Moreover, the effective attenuation bandwidth (EAB: RL < − 10 dB ) is ~6.94 GHz under 1.26 mm, which covers the X- and Ku- band. Compared to pristine Ce 2 Fe 17 N 3-δ absorber, the Ce 2 Fe 17 N 3-δ @SiO 2 endows boosted EMW absorbing performance and broad bandwidth under lower thicknesses. The enhanced related performance is mainly attributed to the optimized impedance matching because of the silica coating.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 15
·12476-12489
·
IF 2.779
Wang Xinyang,Wei Shicheng,Liang Yi,Dong Chaofang,Wang Yujiang,Huang Yuwei,Li Linwei,Wang Bo
RGO/Fe 3 O 4 /FeCO 3 -based composite was prepared by a one-step hydrothermal method. The microscopic morphology and structure were studied using analytical techniques including scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The electromagnetic parameters and the wave absorption properties of the composite/paraffin mixture were analyzed by the vector network analyzer. It is divulged that the FeCO 3 spheres, Fe 3 O 4 spheres, and the RGO sheets form a fluffy structure rich in microscopic cavities, as well as a good conductive network through the sphere–sheet and sphere–sphere interlap mechanisms, which significantly improves the absorbing performance of the composite. The composite can achieve a maximum reflection loss of − 37.9 dB at a frequency value of 13.9 GHz with a matching thickness of only 6.8 mm. The matching thickness can be adjusted in the range of 5.2–10.0 mm in order to attain a flexible adjustment of the effective microwave absorption band of 9.9–18.0 GHz. Combined with the first-principles calculations, compositing reduces the electron migration energy barrier and thus improves the charge transferring capability. Meanwhile, the interaction of the different components leads to the formation of a special charge transferring channel and the increase of carrier concentration, which enhances the charge transport, as well as the absorbing capacity of the absorbing material.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Lan Long,Yaqin Zhu,Chunmei Zhang,Kunming Liu,Shaohua Jiang
The absorption performance of broadband electromagnetic waves is of utmost importance in safeguarding diverse electronic equipment against electromagnetic wave pollution, necessitating materials with low density, thin thickness, and cost-effectiveness to be employed. This study presents the successful synthesis of biomass-derived carbon (BC) composites via the hydrothermal method, utilizing moss coated with flower-like CuS. The CuS was uniformly dispersed on BC matrix, contribute to dipole polarization relaxation. The formation of heterogeneous interfaces between CuS and the BC phase resulted in significant polarization loss. Additionally, the wrinkled BC and flower like CuS constructed by nanosheets boosted scattering of electromagnetic wave due to its large specific surface area, which can provide additional channels for charge transfer and avail dissipation of electromagnetic wave energy. With an efficient absorption bandwidth (EAB) that encompasses the whole X band, the electromagnetic waves absorption (EMA) performance of CuS/BC composites was able to reach a minimum reflection loss of − 28.8 dB.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Lei Jia,Linwen Jiang,Jiawen Hu,Jiawei Jin,Siqin Yan,Anhua Wu,Xiaofeng Zhang
Optimizing the impedance matching via electromagnetic adjustment is considered an effective strategy to accomplish exceptional electromagnetic wave absorption (EMA) performance. Here, we report an efficient and green process to obtain the carbonitriding FeCoNiCr high-entropy alloys (HEAs) with flake-shaped morphology by using organic cyanide (Dicyandiamide, C2H4N4) as nitrogen and carbon sources. The carbonitriding effects on the phase structure, magnetic properties, mechanical hardness, corrosion resistance, high-temperature oxidation resistance, and EMA performances were investigated systematically. The carbonitriding process optimized the impedance match by decreasing the dielectric constant via introducing the nonmetallic C and N. The #CN10 sample exhibited outstanding EMA performances with a minimum reflection loss of −32.3 dB at 7.89 GHz and a broad effective bandwidth of 4.46 GHz, which covered the majority of X-band. In addition, the carbonitriding FeCoNiCr HEAs had great mechanical properties, excellent corrosion resistance, and high-temperature oxidation resistance, indicating excellent adaptability to harsh environments as well as good EMA performances. This work provides a new idea for the preparation and design of carbonitriding EMA materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Shouyu Ren,Qian Chen,Yuxin Jin,Xiaohui Liang,Cao Wu,Yu Zhang,Zengming Man,Zhou Chen
Diverse phases of Fe2O3 manifest distinct physical and chemical attributes. Herein, Fe2O3 and Fe2O3@C dodecahedrons with the yolk-shell structure were prepared by controllable pyrolysis of MIL-88 MOFs with different processes. The corresponding pyrolytic stages in air were proposed, followed closely via a similar self-oxidation/reduction procedure in the N2 atmosphere. In terms of microwave absorption performance, the hollow α-Fe2O3@C nanocomposites with the yolk-shell structure could facilitate the dielectric loss, and the interfaces between α-Fe2O3 and C promote the dissipation of an electromagnetic wave, which improve electromagnetic attenuation capability and enrich the loss mechanism of Fe2O3 collaboratively. Due to its carbon-coated hollow structure, αγ-Fe2O3@C nanocomposites calcinated at 400 °C exhibit the best ability for electromagnetic energy conversion. The device has a matching thickness of 2.25 mm, an effective absorption bandwidth of 11.2 to 15.64 GHz, and a total width of 4.44 GHz. Its highest reflection loss (RL) is −52 dB at 8.6 GHz (X band). In the range of −80 < θ < 80, the maximum radar cross section (RCS) reduction of α-Fe2O3@C is greater than 20 dB m2. A great deal of attention has been paid to theoretical simulations of RCS because of its reasonable composition and low-cost features. This work breaks ground for fabricating a MIL-88-derived electromagnetic wave absorber via the enlightenment of RCS simulations.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CARBON
·
2021
·
IF 9.594
Yijie Liu,Zhengjun Yao,Jintang Zhou,Liqiang Jin,Bo Wei,Xiaoxuan He
The green and facile strategy of producing high efficiency microwave absorption materials (MAMs) has attracted wide attention, but remains a challenge. In this work, polydopamine (PDA) was used as carbon source and nitrogen source, polyvinylpyrrolidone (PVP) was used as protective layer and dispersant, and nanoparticles with concave cube morphology were prepared by self-template eco-friendly method. By adjusting the addition amount of PDA and PVP, the MOF derived materials with three morphologies of pure ZIF-67 nanoparticles , core-shell adhesion cube and concave cube can be precisely controlled. Compared with the other two kinds of absorbers, the sample with concave cube morphology shows excellent electromagnetic wave absorption (EMA) performance. Furthermore, the excellent EMA performance comes from the efficient electron transport channel with unique concave cube morphology, multi-interface polarization process and Co nanoparticles high impedance matching. The analysis demonstrates that when the filling ratio of the concave cube sample is 15%, its effective absorption bandwidth is 5.97 GHz, which can basically cover the Ku band (12.0–18.0 GHz), and the corresponding thickness is 1.88 mm. Our research provides a meritorious approach for the design and preparation of high efficiency MAMs by considering the effects of the morphology and filling ratio of the absorber comprehensively.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Huihuang Shen,Changdong Ju,Junjun Wang,Huabo Huang,Jiayou Ji,Liang Li
There is a challenge to boost the electromagnetic wave absorption performance of magnetic carbon-based materials by rationally adjusting the structure of MOF. In this paper, nanoclip-shaped polypyrrole (PPy) was wrapped on the surface of the Co/C nanoparticle derived from Co-MOF via in-situ polymerization of pyrrole with the help of cetylammonium bromide. The electromagnetic parameters of prepared Co/C@PPy can be easily tuned by adjusting the feed ratio of PPy to Co/C. The optimum value of reflection loss (RL) for Co/C@PPy is −45.49 dB at 2.4 mm and 15.12 GHz when the feed ratio of pyrrole to Co/C is 200 μL to 80 mg, and the effective absorption bandwidth (EAB, RL ≤ −10 dB) reaches 5.97 GHz (11.76–17.73 GHz) at the matching thickness of 2.5 mm. This study paves the way for further design and preparation of the nanocomposites based on MOF-derived nanostructures with excellent EMW absorption performance.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2024
·Vol. 31
·期 11
·2508-2517
·
IF 5.6
Zhang Yahong,Zhang Yi,Liu Huimin,Li Dan,Wang Yibo,Xu Chunchao,Tian Yuping,Meng Hongjie
Facing the complex variable high-temperature environment, electromagnetic wave (EMW) absorbing materials maintaining high stability and satisfying absorbing properties is essential. This study focused on the synthesis and EMW absorbing performance evaluation of TiN/Fe 2 N/C composite materials, which were prepared using electrostatic spinning followed by a high-temperature nitridation process. The TiN/Fe 2 N/C fibers constructed a well-developed conductive network that generates considerable conduction loss. The heterogeneous interfaces between different components generated a significant level of interfacial polarization. Thanks to the synergistic effect of stable dielectric loss and optimized impedance matching, the TiN/Fe 2 N/C composite materials demonstrated excellent and stable absorption performance across a wide temperature range (293–453 K). Moreover, TiN/Fe 2 N/C-15 achieved a minimum reflection loss (RL) of −48.01 dB and an effective absorption bandwidth (EAB) of 3.64 GHz at 2.1 mm and 373 K. This work provides new insights into the development of high-efficiency and stabile EMW absorbing materials under complex variable high-temperature conditions.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2025
·
IF 14.3
Zifan Zou,Liang Xu,Ji Zou,Shuaihang Qiu,Jingjing Liu,Wei Ji,Wenwen Wu,Zhenhao Han,Weimin Wang,Zhengyi Fu
High-entropy borides (HEBs) are emerging as promising candidates for extreme environmental applications due to their exceptional thermal stability, mechanical properties, and tunable electromagnetic properties. This study presents the first systematic investigation of rare-earth-doped deca-component high-entropy borides, (TM 0.9 RE 0.1 )B 2 , (TM = Zr, Hf, Nb, Ta, Ti, W, Cr, V, Mo and RE = Sc, Y, Gd, Dy, Ho, Er, Lu, Sm, Eu, Tm, Tb, Pr, Yb). Evaluations of multiple descriptors, including electron work function and mixing enthalpy, revealed that Sc-containing decaboride (HEB10-Sc) exhibits superior single-phase formation capability. In contrast, the widely used valence electron concentration parameter proved inapplicable due to identical outer-electron counts across rare-earth elements. Boro/carbothermal reduction (BCTR) experiments at 1650°C, employing transition metal oxides, rare-earth oxides, and B 4 C as precursors, demonstrated that Sc uniquely enables the formation of a single-phase diboride with nine group IVB-VIB transition metals, unlike other rare-earth dopants. The phase evolution mechanism during the BCTR process was elucidated: ScBO 3 , formed in situ during BCTR, exhibits greater reducibility resistance than the most refractory HfO 2 , thereby suppressing polyboride formation (common in other rare-earth systems) and facilitating single-phase HEB10 formation. The resulting HEB10-Sc displays outstanding electromagnetic wave absorption performance, achieving a reflection loss (RL) of −35.3 dB at 10.6 GHz (3 mm thickness) and an effective absorption bandwidth of 4.7 GHz in the X and Ku bands. These findings underscore the critical role of rare-earth doping in tailoring the structural and functional properties of high-entropy borides, offering a pathway to design advanced multifunctional materials for extreme environments such as thermal protection and high-temperature electromagnetic absorption in aerospace and electronic applications.
研究领域:
材料科学
·
物理化学
✓ 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）