Journal of Materials Research and Technology-JMR&T
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2024
·
IF 6.2
Qian Ma,Rong Qiang,Yulong Shao,Xiao Yang,Yi Chen,Rui Xue,Fangjie Ren,Yuancheng Ding,Lei Rong,Jingbo Fang,Qing Miao,Zheng Guo
Nowadays, the issue of electromagnetic pollution has become increasingly prominent, underscoring the critical importance of developing high-performance microwave absorbers. This study put forwards the synthesis process of two-dimensional (2D) FeCo/Co 8 FeS 8 /C carbon nanosheets, wherein CoSO 4 and FeCl 3 serve as inorganic salt templates, and dopamine functions as the carbon source. FeCo alloy nanoparticles and Co 8 FeS 8 nanoparticles are loaded on the surface of the carbon layer. 2D structure forms the conductive network, which proves advantages in establishing efficient electronic channels and minimizing conduction losses. The carbon component increases the dielectric constant of the composite and improves its impedance matching, and the FeCo alloy provides a certain ML. The synergistic effect between these components significantly contributes to the exceptional microwave absorption performance of the composites. Accordingly, the minimum reflection loss ( R L min) of FeCo/Co 8 FeS 8 /C composite reaches −47.4 dB, its effective absorption bandwidth (EAB) reaches 5.3 GHz. In particular, CST confirms that radar cross-section reduction value of FeCo/Co 8 FeS 8 /C composite can reach 20.2 dB m 2 in the range of −90° < phi< 90°, indicating a high microwave attenuation ability. The study introduces a novel strategy for advancing the development of two-dimensional carbon-based absorption materials.
研究领域:
材料科学
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电磁学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 10
·期 3
·1547-1559
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IF 12.732
Ran Liu,Gaiping Du,Bin Liao,Weixin Xiao,Zhenguo An,Jingjie Zhang
Due to their multiple dissipation mechanisms, low density and easily tailored impedance matching, heterogeneous hollow structures are promising candidates for microwave absorbents towards wideband absorption and lightweight design. In this work, a new type of hollow microspheres with a porous carbon shell embedded with crystalline FeCo alloy nanoparticles have been prepared via a stepwise spray drying–calcination strategy. The effects of both the FeCo/C molar ratio and the calcination temperature on the structure and property of the porous hollow microspheres (PHMs) have been studied. It is found that the effective absorption bandwidth of the as-prepared FeCo/C PHMs surpassed 7.44 GHz at a matching thickness of 2.64 mm, which covers the full Ku-band. Moreover, with an elevated calcination temperature, high microwave absorbing performance can be achieved at a much reduced matching thickness. A probable absorbing mechanism has been proposed involving the synergistic effect of the hollow interior, the porous shell structure, and the electric and magnetic dissipation due to the coexistence of carbon and magnetic metals. This work opens a new pathway to synthesize microwave absorbents with a heterogeneous hollow structure, and may shed some light on the design and controlled preparation of other hollow structures with various shell compositions.
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
DIAMOND AND RELATED MATERIALS
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2021
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IF 3.315
Yang Fan,Jingyu Wang,Ximing Zhang,Zaisheng Zhu,Yin Liu,Atian Xie,Hongcun Bai,Ling Bing Kong
The introduction of magnetic materials into carbon materials has been proved to be an effective approach to tailor and improve electromagnetic wave (EM) absorption. In this study, coal-based carbon/FeCo (CBC/FeCo) magnetic composites were designed and prepared. These samples exhibit layered stripes similar to graphite. In these novel composites, the FeCo alloy exhibits strong magnetic loss and the coal-based carbon (CBC) not only acts as an impedance matching medium but also exhibits excellent dielectric loss. Therefore, the CBC/FeCo composites exhibit strong EM absorption, with minimum reflection loss ( RL min ) of −60.81 and −49.82 dB at thicknesses ( d ) of 1.38 and 2.45 mm, respectively. Compared with pure coal-based carbon and FeCo alloy, the improvement in EM absorption can be mainly attributed to the improved impedance matching and enhanced multiple interfacial polarization . In addition, the effects of reaction temperature and the content of FeCo on EM absorption performance of the composites were also studied. Specifically, samples of S-2 with process temperature at 800 °C for 2 h and the FeCo alloy mass loading was 0.3 g (CBC/FeCo-0.3), the EM absorption performance was optimized. It is believed that the CBC/FeCo composites could be promising candidates for EM absorbers.
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
ChemSusChem
·
2024
·
IF 7.5
Feng Zhang,Yu Lei,Guang Li,Yangchen Xie,Xinjia Guo,Xiaoyan Zhang,Xianyou Wang
Graphical ORR or OER : CoFe layered double hydroxide (CoFe-LDH) nanosheets are deposited on nitrogen-doped graphite-carbon polyhedra with FeCo alloy nanoparticles to form a composite bifunctional oxygen electrocatalyst. The FeCo/LDH-NGCP catalyst shows wonderful ORR and OER bifunctional electrocatalytic performance, which is superior to that of the precious metal based catalyst. Reasonably screening the targeted oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) constituents and constructing high-efficiency and stabilized ORR/OER bifunctional electrocatalysts are pivotal for the advancement of rechargeable zinc-air batteries (ZABs). Here, CoFe layered double hydroxide (CoFe-LDH) nanosheets are deposited on nitrogen-doped graphite-carbon polyhedra with FeCo alloy nanoparticles (FeCo/LDH-NGCP). Due to the synergic effect between FeCo-NGCP, CoFe-LDH and FeCo/LDH-NGCP, the electrocatalyst with the abundant and accessible active sites can provide good charge/mass transfer, and thus shows wonderful ORR and OER bifunctional electrocatalytic performance. In ORR tests, FeCo/LDH-NGCP catalyst displays larger half-wave potential (E 1/2 , 0.89 V vs. 0.85 V), higher limiting current density (J L , 5.91 mA/cm 2 vs. 5.14 mA/cm 2 ) and better stability than commercial Pt/C. As for OER, FeCo/LDH-NGCP possesses a smaller overpotential (η) of 299.6 mV at a current density of 10 mA/cm 2 and more durable stability than commercial RuO 2 (330.6 mV). Furthermore, in ZAB tests, the cycling stability of ZAB-FeCo/LDH-NGCP (over 470 h) outperforms the ZAB-Pt/C+RuO 2 (92 h) with commercial electrocatalyst (Pt/C+RuO 2 ). Therefore, the FeCo/LDH-NGCP catalyst offers a new perspective to construct ZABs bifunctional catalysts and their commercial application in ZABs.
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
产品关联
DOI
PubMed
高影响因子
Materials Today Communications
·
2025
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IF 4.5
Yuntong Wen,Hao Bian,Yongpeng Ran,Yonghao Xie,Minmin You,Huimin Wen,Liyun Shi,Jingquan Liu,Zude Lin
The 2D Ti 3 C 2 T x MXene anchored with magnetic particles has garnered significant attention due to its superior electromagnetic shielding performance and low reflection coefficient. However, current research on MXene-anchored magnetic particles faces several challenges, including complex fabrication processes, difficulty in controlling compositional ratios, the predominant use of spherical magnetic particles. In this work, by employing surfactants, FeCo alloy and Ni flakes were uniformly anchored onto MXene, the preparation process of the composite is simple and facilitates better control over the ratios of individual samples. Due to the unique structure formed by the intercalation of FeCo alloy and Ni flakes within the MXene layers, M-FC-N-35 exhibits an average electromagnetic shielding effectiveness of 61.2 dB within the Ku-band and maintains a reflection coefficient as low as 0.69. Additionally, the M-FC-N-35 composite was applied to the surface of the temperature sensor casing. It was found that under an electromagnetic field strength of 200 V/m and within a frequency range of 6–18 GHz, the temperature measurement deviation was reduced to 9.35 % of that of the sensor without the shielding material, demonstrating high electromagnetic interference resistance. This work provides guidance for simplifying the fabrication process of MXene composites with magnetic metals and enriching the system of electromagnetic shielding materials.
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
JOURNAL OF HAZARDOUS MATERIALS
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2021
·
IF 10.588
Dandan Zhu,Meijuan Chen,Yu Huang,Rong Li,Tingting Huang,Jun-ji Cao,Zhenxing Shen,Shun Cheng Lee
Formaldehyde is a typical indoor air pollutant that has posed severely adverse effects on human health. Herein, a novel FeCo alloy nanoparticle-embedded nitrogen-doped carbon (FeCo@NC) was synthesized with the aim of tailoring the transition-metal d-band structure toward an improved formaldehyde oxidation activity for the first time. A unique core@shell metal–organic frameworks (MOFs) architecture with a Fe-based Prussian blue analogue core and Co-containing zeolite imidazole framework shell was firstly fabricated. Then, Fe and Co ion alloying was readily achieved owing to the inherent MOF porosity and interionic nonequilibrium diffusion occurring during pyrolysis . High-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure spectra confirm that small FeCo alloys in situ form in FeCo@NC, which exhibits a higher formaldehyde removal efficiency (93%) than the monometallic Fe-based catalyst and a remarkable CO 2 selectivity (85%) at room temperature. Density functional theory calculations indicate the number of electrons transferred from the metal core to the outer carbon layer is altered by alloying Fe and Co. More importantly, a downshift in the d-band center relative to the Fermi level occurs from − 0.93 to − 1.04 eV after introducing Co, which could alleviate the adsorption of reaction intermediates and greatly improve the catalytic performance.
研究领域:
环境科学
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材料科学
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化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
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IF 9.4
Kunpeng Song,Guanghui Li,Junchen Yu,Tianyue Zheng,Jingyu Wang
Efficient methods for preparing carbon nanotube (CNT)-confined metal catalysts are of great significance for electrocatalysis. Hence, in this study, Fe and Co promoters were added to the precursors of commercial carbon black and melamine to form N -doped CNTs confined bimetallic catalysts (FeCo@ N -CNTs) via in situ pyrolysis. The FeCo@ N -CNT catalysts exhibited a bamboo-like morphology with FeCo alloy nanoparticles encapsulated in the CNTs and high activity toward the oxygen reduction reaction, with a half-wave potential of 0.864 mV, higher than that of commercial Pt/C (0.827 mV) in alkaline solutions. The catalytic performance is attributable to the synergistic effects between the FeCo alloy and N -doped CNT structure. Moreover, the confinement of the FeCo nanoparticles inside the CNTs imparted the prepared catalysts with resistance to methanol poisoning and long-term stability. This versatile method of synthesizing CNTs directly from carbon black provides a new strategy for preparing high-performance non-precious-metal-based N -doped CNT catalysts for practical fuel cell applications.
研究领域:
材料科学
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电化学
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能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2020
·
IF 3.807
Dingding Duan,Yaping Ding,Li Li,Guohong Ma
A high-performance melatonin sensing platform based on carbon nanofibers arrays decorated with FeCo alloys is described. A kind of carbon nanofiber based on FeCo bimetallic alloy was prepared by electrospinning. The synergistic effect of FeCo enhanced the electrocatalytic property and electron transfer ability of the materials. In addition, on the basis of the composite material, we study the electrooxidation behavior of melatonin and its reaction mechanism, and build a rapid succession of quantitative detection of melatonin electrochemical sensor with the detection range of 0.08–400 um and a detection limit as 2.7 nm. Compared to previous reports, this melatonin sensor possesses excellent properties and wide detection range.
研究领域:
材料科学
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分析化学
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生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2020
·
IF 7.489
Hu Liu,Dong-Hui Yang,Xu-Yun Wang,Jiangwei Zhang,Bao-Hang Han
Exploiting low cost and durable electrocatalysts with high efficiency for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is of great significance for energy conversion and storage applications. Herein, a hybrid electrocatalyst of FeCo alloy nanoparticles embedded in a porous N -doped carbon was prepared via a pyrolysis process of low-cost melamine sponge and mass-produced metal–polyphenol network. Benefting from the metal coordination of metal–polyphenol network and abundant N source of melamine sponge, the metal–N moiety and FeCo alloy nanoparticles (wtih a diameter around 50 nm) encapsulated in a N -doped graphene-like carbon layer were formed in-situ. Such intimate integration of graphene-like carbon-encapsulated FeCo alloys, metal–N active species, and porous structure is conducive to improve the catalytic activity and increase the catalytic durability in alkaline media. As a consequence, the as-prepared electrocatalyst exhibits the pronounced activity toward ORR, OER, and HER simultaneously under alkaline condition, particularly on the performances of potential, stability, and methanol tolerance.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2023
·Vol. 15
·期 45
·18395-18406
·
IF 6.7
Kun Wang,Liyuan Wang,Jinrui Huang,Ye Chen,Xupo Liu,Tianfang Yang,Gangya Wei,Shuyan Gao
The introduction of transition bimetallic alloys can effectively improve oxygen reduction reaction (ORR) activity. However, the alloy particles are inclined to dissolve under harsher conditions, resulting in a serious decrease in catalytic activity and stability. Herein, an efficient ORR catalyst, FeCo alloy nanoparticles (NPs) encapsulated in N,S co-doped carbon nanotubes (FeCo10-NSCNTs), was developed through a self-catalyzed growth strategy. Due to the delicate structural design, the N,S co-doped structure can effectively improve the ORR performance by modulating the electronic properties and surface polarity of the carbon substrate, and the randomly connected carbon nanotube structure with large specific surface area can further enhance the adsorption and dissociation of gas molecules, accelerating the kinetics of gas participation in the reaction. Carbon-encapsulated FeCo alloys are beneficial for improving catalytic activity and durability. The FeCo10-NSCNTs displayed excellent ORR activity with a half-wave potential of E1/2 = 0.84 V and robust stability of 13 k cycles. More impressively, the assembled liquid-state Zn–air battery (ZAB) with FeCo10-NSCNTs as the air-electrode delivers an output power density of 146.68 mW cm−2 along with excellent operation durability. The assembled all-solid ZAB has good cyclic stability under 0–180° bending conditions. The synthesized N,S co-doping, carbon nanotubes and FeCo alloys provide important guidance for the construction of cheap non-noble metal–carbon hybrid nanomaterials.
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
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2024
·Vol. 14
·期 22
·1831
·
IF 4.4
Dianfeng Cao,Yuwen Li,Chao Lv,Yongtao An,Jiangfeng Song,Mingcan Li,Xin Zhang
Catalytic methane decomposition (CMD) reaction is considered a promising process for converting greenhouse gas CH 4 into hydrogen and high-value-added carbon materials. In this work, a series of Al 2 O 3 -supported FeCo alloy catalysts were successfully prepared in the CMD process. Compared to the pre-reduced catalysts, the in situ reduced FeCo alloy catalysts showed higher methane conversion rates, with the highest reaching 83% at 700 °C, due to the finer active nanoparticle size and greater exposure of active site. Furthermore, the time-on-stream tests demonstrated that the catalytic activity of in situ reduced FeCo alloy catalysts could remain above 92.3% of the highest catalytic activity after 10 h. In addition, TEM analyses of the carbon products from the CMD in situ reduced catalysts revealed the production of carbon nanofibers and nanotubes several microns in length after the reaction. This indicates that the in situ reduced FeCo alloy catalysts more effectively promoted the growth of carbon nanofibers. These results could provide a viable strategy for future methane decomposition development aimed at producing hydrogen and high-value carbon.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Yusheng Li,Yun Feng,Li Li,Keyan Wu,Xiangjie Bo,Jianbo Jia,Liande Zhu
Due to the obstacle of sluggish kinetics on cathode of fuel cells and metal–air batteries, developing low-cost and durable electrocatalysts to replace the platinum-based catalysts still remains a grand challenge. Here, we describe a simple self-template approach to synthesize N-doped mesoporous carbon nanocages (FeCo@NC) embedded with FeCo alloy nanoparticles as oxygen reduction reaction (ORR) electrocatalyst. The resulting heterostructure is derived from corresponding PBA@PPy composites, which are pre-prepared by polymerization of polypyrrole (PPy) layer on Prussian blue analogue (PBA) nanocubes. The FeCo alloy nanoparticles with an average particle size of ∼10 nm are well dispersed and confined within the shell of carbon nanocages. Benefiting from the mesoporous structure and the synergetic interaction of binary metals, the optimized FeCo@NC-3-800 electrocatalyst exhibits comparable ORR performances (0.83 V for half-wave potential (E 1/2 ), 5.323 mA cm −2 for limiting current density (J k )), superior durability and excellent methanol tolerance to the commercial Pt/C (20 wt%). This work provides an appropriate strategy for general, efficient and practical synthesis of more promising non-precious metal electrocatalyst with high ORR activity.
研究领域:
材料科学
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电化学
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能源科学
✓ 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）