CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lu Tang,Siyu Chen,Donghong Wang,Zhiyong Chen,Jimei Xue,Zhijun Wang,Ying Li,Hanjun Wei
The inherent dielectric properties and thermal stability of transition metal carbides (TMCs) have generated significant interest because of their potential use in electromagnetic (EM) wave applications at various temperatures. However, the high relative complex permittivity and conductivity of TMCs can cause impedance mismatch issues when utilized as absorbers, thereby limiting their effectiveness in absorbing EM waves. To solve these problems, ZrC/ZrO 2 –SiOC composites with a porous lamellar structure were prepared using polymer-derived ceramics (PDC) technology, which involved dispersing zirconium carbide (ZrC) into modified polysiloxane (PSO). The resulting ZrC/ZrO 2 –SiOC composite (with 5 wt% ZrC content sintered at 900 °C) achieved remarkable EM wave absorption performance , with a minimum reflection loss (RL min ) of −33.52 dB at 13.0 GHz and an effective absorption bandwidth (EAB) extending up to 7.75 GHz. This exceptional absorption of EM waves is due to the synergistic interplay of various factors such as interface polarization, dipole polarization, and conduction loss . Moreover, the composites exhibit a minimal weight loss of less than 2 % when exposed to air at temperatures ranging from 25 to 1200 °C. This study not only broadens the application possibilities of TMC materials in microwave absorption but also highlights their potential for further improvement and deployment in high-temperature environments.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CARBON
·
2018
·
IF 7.082
Yican Wang,Wenlong Wang,Jing Sun,Chenggong Sun,Yukun Feng,Zhe Li
Microwave-metal discharge was proposed as a facile methodology to prepare unique Fe-cored carbon nanocapsules (Fe@CNCs) with high purity, novel stability and extraordinary electromagnetic wave (EMW) absorption performance . The effect of microwave power, irradiation time and cyclohexane/ferrocene ratio on the production of Fe@CNCs was examined and the properties of the nanocapsules, such as their Fe content , phase, yield, degree of graphitization and associated microstructures were investigated in detail. It was found that the prepared Fe@CNCs, which can easily be separated from the reaction system, displayed exceedingly high electromagnetic wave (EMW) absorption performance over the 2–18 GHz range. At the minimal reflection loss (RL) values over −10 dB, the EMW absorption bandwidth can reach up to 13.8 GHz with an absorber thickness of 1.5–5 mm. In addition, novel thermo-oxidative stability and super anti-corrosion property were also obtained for the Fe@CNCs as no signs of any corrosion or oxidative degradation loss were observed from the accelerated degradation tests in air and acid at temperatures up to 420 °C. The exceedingly high EMW absorption performance coupled with the superior anti-degradation and anti-corrosion properties of the prepared nanocomposite microcapsules highlights the novel capability of microwave-metal discharge in synthesizing advanced metal-cored nanocarbon microcapsules with promising application potentials in diverse fields, such as but not limited to microwave absorption, EM shielding and advanced separations etc.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Gaoqiang Yu,Mingquan Ye,Aijun Han,Qingzhong Liu,Yaojing Su,Cheng Chen
Developing composite materials with a rational composition structure has been a critical strategy to obtain superior electromagnetic (EM) wave absorption materials. CoNi/MoSe 2 composites were synthesized by a two-step method in this work. Firstly, the flower-like MoSe 2 was synthesized by hydrothermal method , and then the CoNi alloy was loaded on the MoSe 2 surface by an electroless plating method. It is worth noting that in this paper, PdCl 2 was not used for activation during the electroless plating process, and the flower-like structure of MoSe 2 was not destroyed. In order to investigate the effect of different Co/Ni molar ratios on the absorption performance of the CoNi/MoSe 2 composites, three samples with Co to Ni molar ratios of 1:3, 1:1, 3:1 and two other samples with only one metal (Ni or Co) were prepared. The analysis results show that the minimum reflection loss(RL) value of Ni/MoSe 2 is −18.01 dB and the maximum effective absorption bandwidth(EAB) of Co/MoSe 2 is 2.16 GHz. In comparison, the CoNi/MoSe 2 composite exhibits the best EM wave absorption performance when the Co/Ni ratio is 1:3, and the minimum RL can reach −48.6 dB at a matching thickness of only 1.8 mm. And when the matching thickness is 1.4 mm, the broadest EAB is 3.76 GHz. Therefore, this work provides a new research idea for the design of broadband and efficient EM wave absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Jingyu Wang,Shaocong Zhong,Muyao Liu,Ruize Zhang,Xingeng Liu,Yaling Huang,Xinyu Liu,Xinyu Wang,Dongdong Lv,Long Xia
The preparation of highly absorbing and high-performance electromagnetic wave-absorbing materials remains a significant challenge. In this paper, carbon matrix composites modified with sodium inorganic salts (CMS) have been successfully prepared by using the solvent evaporation method in combination with the hydrothermal treatment and high temperature carbonization processes. The composition of the product can be manipulated by varying the material ratios, which in turn affects the interface and dielectric properties of the material. Sodium carbonate (Na 2 CO 3 ) was produced as a transition phase between sodium silicate and carbon matrix due to high temperature. According to differential charge density a significant charge accumulation found between the interfacial of Na 2 CO 3 and carbon layer is helpful to polarization. The synergistic effect of polarization and conduction loss due to the formation of multiple heterogeneous interfaces and carbon matrix results in excellent electromagnetic wave absorption performance. The minimum reflection loss (RL min ) is −55.49 dB when the thickness is 3.1 mm. Furthermore, CMS composites exhibit notable flame retardancy and thermal insulation properties, rendering them suitable for a diverse range of applications. These remarkable achievements provide new ideas for the design and development of efficient electromagnetic wave absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2023
·
IF 10.9
Meng Ma,Qi Zheng,Xinci Zhang,Lin Li,Maosheng Cao
Electromagnetic radiation pollution has become a serious threat, which will harm human health and interfere with electronic devices. However, it is still a challenge to develop high-efficiency electromagnetic wave absorbers with wide frequency band and strong absorption, especially for realizing the features of multi-bands absorption. Herein, VSe 2 /CNTs nanocomposites were successfully synthesized with crosslinked CNTs distributed on VSe 2 nanoclusters composed of nanosheets . Importantly, the electromagnetic properties and absorption performance of the VSe 2 /CNTs nanocomposites can be effectively tailored by changing the hybrid ratio of CNTs and VSe 2 nanosheets (VSe 2 -NSs). The increase of CNTs content promotes the formation of a conductive network and leads to the increase of permittivity. The VSe 2 /CNTs nanocomposite with CNTs of 40 mg exhibits the best electromagnetic wave absorption performance, the minimum reflection loss ( RL ) reaches −57.53 dB at 5.52 GHz and is about 6 times more than VSe 2 -NSs. Meanwhile, the VSe 2 /CNTs nanocomposite with CNTs of 30 mg shows dual-bands absorption performance with a minimum RL value of −50.06 dB at 3.84 GHz and the total effective absorption bandwidth of 3.32 GHz. This result proves that VSe 2 /CNTs nanocomposites can be promising candidates as high-efficiency electromagnetic wave absorption material and provides a feasible idea for designing a high-performance electromagnetic wave absorber.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2023
·
IF 4.1
Xinbo Wu,Wenhui Zhang,Dazhi Wang,Weijie Cai,Shangru Zhai
In this work, using porous PAES as the precursor, a series of Fe 9 S 10 /Carbon composites (PAES-Fe) with excellent electromagnetic wave (EMW) absorbing features were successfully prepared via in situ oxidation technique. The analysis results indicate that the obtained composite material has characteristics such as multi-level pore structure and large specific surface area. Its excellent EMW absorption mechanism is mainly attributed to conductive loss, interface polarization, and dipole polarization. Most importantly, by adjusting the type of Polyvinyl Pyrrolidone (PVP), the pore size of the composite can be optimized to obtain the best impedance matching. The as-prepared PAES-Fe nanomaterials presented the attractive EMW absorption performance in terms of reflection loss (RL), absorption bandwidth as well as absorption layer thickness. When controlling the composite macropore size at 2 μm, the mesoporous pore size was 2–6 nm, the specific surface area was 189.2 m 2 /g, and the pore volume (PV) reached 0.130 cm 3 /g. With the thickness of 2 mm, the minimum RL of PAES-Fe-P reached −31.313 dB at 5.46 GHz. Hence, this type of nanocomposites with tunable pore size characteristics and hierarchical pore structure may have enormous potential for application of EMW absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Dongjie Jia,Xianyu Li,Rongyan Cai,Bochao Ma,Qixian Zhao,Tonglin Chigan,Peipei Yang
Two-dimensional MXene and its composites are among the most attractive electromagnetic wave absorption (EMA) materials due to their unique structure. While previous studies have investigated 2D/2D MoS 2 /Ti 3 C 2 T x heterojunctions for EMA, there is still a need for further adjustments to interface structure to enhance polarized electron density and electron transfer capacity. In this study, Cl-Ti 3 C 2 T x was prepared by Lewis acid molten salt etching of Ti 3 AlC 2 , and S-Ti 3 C 2 T x was prepared by replacing Cl with S. MoS 2 nanosheets were grown on the surface of S-Ti 3 C 2 T x by a simple hydrothermal method, forming a Ti-S-Mo covalent interface. The EMA properties of the composites were further optimized by adjusting the interface oriented polarization and electronic structure through Ni doping. Compared to MoS 2 /TiO 2 /Ti 3 C 2 T x , the electromagnetic wave absorption performance of Ni-MoS 2 /TiO 2 /Ti 3 C 2 T x had been significantly improved. When the Ni doping amount was 0.086 mmol, the minimum reflection loss of Ni-MoS 2 /TiO 2 /Ti 3 C 2 T x could reach −48.04 dB at 8.64 GHz, with an effective absorption bandwidth of 3.28 GHz. This study provides theoretical basis and experimental evidence for the follow-up research of MXene-based composite EMA materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Jun Weng,Yanan Liu,Xiaoxiao Huang
Metal-Organic framework (MOF) derivatives have been applied as electromagnetic wave absorption (EMA) materials in recent years. Carbon nanotubes (CNTs) can achieve in situ growth on the surface of MOF derivatives. However, there is limited research on the EMA performance by regulating the morphology of the in situ grown CNTs. In this work, we prepared MOF-derived Ni@carbon nanotubes (Ni@CNT) with controllable length of CNTs by solvothermal and simple one-step pyrolysis method and revealed the CNT growth mechanism. We further investigated the effect of in situ grown CNT morphology on electromagnetic parameters and EMA performance. In situ grown CNTs of similar length on the surface of MOF derivatives lead to similar electromagnetic parameters. When the length of CNTs is short, the relaxation strength ( Δ ε = ε s − ε ∞ ) is high, leading to excellent microwave absorption performance. For Ni@CNT-600, the reflection loss of −44.4 dB can be achieved at merely 1.72 mm. Finite element (FE) simulation was used to evaluate the EMA mechanism of different samples by calculating electric field and polarization strength. This work has explored the electromagnetic wave absorption performance from the perspective of microstructural tailoring, helpful for understanding the unique role of the in situ grown CNTs on the surface of MOF derivatives and investigating the ultra-thin electromagnetic wave absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Xiongfei Liu,Yi Zhang,Yongling Guo,Xiaozhong Wang
In this study, the focus is on enhancing the microwave absorption performance of magnesium phosphate cement (MPC) by incorporating Fe 3 O 4 @SiO 2 nanocomposites . The resulting MPC, fortified with hollow glass microspheres (HGM) and Fe 3 O 4 @SiO 2 , demonstrates remarkable improvements in absorption efficiency, rapid hardening, early strength , and bonding properties. Through thorough characterization using SEM, XRD, FTIR, and XPS, the uniform distribution and morphology of the Fe 3 O 4 @SiO 2 nanocomposites within the MPC matrix are confirmed. Compared to MPC treated solely with Fe 3 O 4 , the modified MPC shows a 104% increase in absorption peak value with a bandwidth of 1.20 GHz (<10 dB). The addition of SiO 2 promotes the hydration process of Fe 3 O 4 @SiO 2 within MPC, forming a uniform absorption network that enhances electromagnetic absorption efficiency. Moreover, the synergistic effects of impedance matching, multiple scattering, and interfacial polarization contribute to further enhancing microwave 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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Jie Liu,Yurun Feng,Chunmiao Liu,Yanchun Tong,Haibin Sun,Hui Peng,Shigang Wu,Junbin Lu,Hongyu Gong,Xue Guo,Jiao Li
The SiBCN composite fibers with strong electromagnetic wave (EMW) absorption performance were successfully prepared via polymer-derived ceramics (PDCs) and electrospinning methods at relatively lower preparation temperature. The results showed that the in-situ generated free carbon which existed in the matrix in the form of simple substance and was characterized by low crystallinity. The graphite carbon improved the dielectric loss and properties of SiBCN composite fibers. In particular for the SiBCN composite fibers pyrolyzed at 1300 °C, the in-situ generated nano β-SiC crystallization increased the EMW absorption performance significantly. The minimum reflection loss (RL min ) of the SiBCN-3 reached − 54.91 dB at 2.35 mm and the effective absorption band (EAB, RL ≤ −10 dB) reached 4.72 GHz (13.28–18 GHz, 1.75 mm). Hence, the SiBCN fibers prepared at relatively lower temperature give good absorption performance and predict a broader application prospect in the field of EMW absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Physics
·
2023
·
IF 11.5
Ziqing Yang,Xiaosi Qi,Chen Li,Qiqing Liang,Lei Wang,Junfei Ding,Yunpeng Qu,Xiu Gong,Wei Zhong
Interfacial polarization had a great impact on the attenuation of electromagnetic wave . To aggrandize interfacial polarization, a strategy of constructing the abundant interfaces was proposed and investigated. Herein, CoNi nanospheres , CoNi@SiO 2 nanospheres and core@shell CoNi 2 S 4 /Co 9 S 8 @SiO 2 @MoS 2 flower-like multicomponent nanocomposites (MCNCs) were elaborately designed and successfully fabricated through a simple continuous hydrothermal process, classical Stöber method and hydrothermal treatment . The obtained results demonstrated that the elaborately constructed abundant interfaces greatly boosted the polarization loss ability, which resulted in the enhanced interfacial polarization. Therefore, the as-prepared CoNi 2 S 4 /Co 9 S 8 @SiO 2 @MoS 2 flower-like MCNCs presented the superior electromagnetic wave absorption properties (EMWAPs) compared to the CoNi and CoNi@SiO 2 precursors. Furthermore, the EMWAPs of CoNi 2 S 4 /Co 9 S 8 @SiO 2 @MoS 2 flower-like MCNCs could also be further improved by optimizing the hydrothermal temperature and filler loading. The obtained CoNi 2 S 4 /Co 9 S 8 @SiO 2 @MoS 2 flower-like MCNCs presented the excellent comprehensive EMWAPs including strong absorption capability, broad absorption bandwidth and thin matching thickness, which could be attributed to the unique structure, excellent interfacial polarization and synergistic effect. Therefore, this finding not only demonstrated that introducing the abundant interfaces was an effective strategy to strengthen interfacial polarization for the promotion of EMWAPs, but also provided an alternative approach to exploit the novel high-efficiency microwave absorbers.
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 Nano Materials
·
2020
·
IF 0
Xiaopeng Han,Ying Huang,Ling Ding,Yan Song,Tiehu Li,Panbo Liu
High-performance absorbers with laminated and three-dimensional structures for abundant interfaces can improve electromagnetic wave absorption property obviously. Meanwhile, the combination and dispersion of components have a positive effect on the microwave absorption (MA) property for excellent absorption bandwidth. Herein, accordion-like MXene/Co-ZIF and MXene/Ni-ZIF composites were synthesized by electrostatic self-assembly between MXene and metal–organic frameworks (Co-MOF and Ni-MOF) and then pyrolyzed in the H2/Ar mixed atmosphere (Co-MOF and Ni-MOF named as Co-ZIF and Ni-ZIF, respectively, after pyrolysis). The MXene/Co-CZIF 50% composites displayed good absorption performance with the optimal RL value of −60.09 dB at 7.36 GHz and the broadened absorption bandwidth 9.3 GHz (RL < −10 dB). MXene/Ni-CZIF 50% exhibited promising performance with the RL value measured up to −64.11 dB at 5.12 GHz, and possessed the ultrabroad effective response bandwidth of 4.56 GHz (RL < −10 dB). Furthermore, a unique accordion-like structure, magnetic–dielectric synergistic, multiple interface scatterings and reflections, and dipole polarization were said to improve MA properties. This study provided a method for the synthesis of absorbers with tunable electromagnetic properties and wide absorption bandwidth of MXene-based composites.
研究领域:
材料科学
·
电磁学
·
纳米技术
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）