CERAMICS INTERNATIONAL
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2017
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IF 2.986
Wenhu Hong,Shun Dong,Ping Hu,Xiaoguang Luo,Shanyi Du
Enhanced microwave absorption properties of porous PDC-SiC/Si 3 N 4 ceramics were successfully prepared through in situ growth of Si 3 N 4 nanowires (NWs) by the unidirectional freeze casting of Si 3 N 4 /camphene slurries with various polycarbosilane (PCS) contents at 1400 °C in N 2 . Si 3 N 4 NWs were in situ formed in the pore channels via a vapor-solid (VS) mechanism, the content of Si 3 N 4 NWs increased with increasing of PCS content, which tailored the microstructure and mechanical property of porous PDC-SiC/Si 3 N 4 ceramics. With the increase of PCS content, the minimum reflection coefficient (RC) of porous PDC-SiC/Si 3 N 4 ceramic decreased from −20.2 dB to −56.2 dB, and the effective absorption bandwidth (EAB) increased from 5.3 to 7 GHz, demonstrating that the porous PDC-SiC/Si 3 N 4 ceramics decorated with Si 3 N 4 NWs had a superior microwave-absorbing ability, which could be ascribed to the electronic dipole polarization and interfacial scattering enhanced by the various interfaces among Si 3 N 4 , in-situ formed PDC-SiC nanograins, nanosized carbon and Si 3 N 4 NWs phases. These findings provide significance guidance in the development of new broadband EM absorbing materials.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2014
·Vol. 3
·期 4
·1696-1702
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IF 0
Zhonghui Han,Gang Chen,Chunmei Li,Yaoguang Yu,Yansong Zhou
The one-dimensional (1D) cubic Cd0.8Zn0.2S solid-solution nanowires are first prepared by the “levelling effect” of thioglycolic acid (TGA) in a solvothermal process. It exhibits the enhanced transfer and separation efficiency of carriers to improve the photocatalytic H2-production activity. TGA not only serves as the sulphur source but also plays a template medium agent role. Furthermore, no TGA selectivity for diverse solvents to prepare 1D Cd0.8Zn0.2S solid solutions suggests that it also may be extended to the preparation of other 1D metal sulphide solid solutions in diverse solvents.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
ANALYTICAL CHEMISTRY
·
2021
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IF 6.986
Ping Li,Ziwei Zhang,Zhihua Zhuang,Jinhan Guo,Zhongying Fang,Shemsu Ligani Fereja,Wei Chen
Metal oxide semiconductors (MOS) with different nanostructures have been widely used as gas sensing materials due to the tunable interface structures and properties. However, further improvement of the sensing sensitivity and selectivity is still challenging in this area. Constructing appropriate heterogeneous interface structures and oxygen vacancies is one of the important strategies to tune the sensing properties of MOS. In the present study, interfacial heterostructures in PdxW18O49 nanowires (PdxW18O49 NWs) were fabricated and manipulated by doping different Pd contents through a simple hydrothermal process. Relevant characterization proved that the structure and composition of the one-dimensional (1D) nanomaterial can be effectively changed by Pd doping. It was found that the oxygen vacancy concentration increases first with the increase of Pd content, and when the Pd content increases to 7.18% (Pd7.18%W18O49 NWs), the oxygen vacancy content reaches the maximum (52.5%). If the Pd content continues to increase, the oxygen vacancy ratio decreases. The gas sensing investigations illustrated that the PdxW18O49 NWs exhibited enhanced sensing properties than pure W18O49 NWs toward acetone. Among the as-prepared catalysts, the Pd7.18%W18O49 NWs showed the best sensing response and the fastest response-recovery speeds (5 and 10 s, respectively) at a working temperature of 175 °C. In addition, this 1D nanostructure with fabricated heterostructures also delivers a good sensing selectivity and a wide detection range from 100 ppb to 300 ppm, with maintaining excellent performance in the presence of high concentrations of ethanol and carbon dioxide. The excellent gas sensing behavior could be attributed to the generated oxygen vacancies and the heterostructures upon Pd doping. This study offers a novel strategy for the design of high-performance gas sensors for ppb-level acetone sensing.
研究领域:
材料科学
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化学工程
·
传感器技术
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
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2024
·
IF 2.6
Wang Siyi,Liu Hongying,Li Zhongyu,Li Jiayi,Li Lin,Chi Ru’an,Wang Shiquan
One-dimensional copper sulfide (CuS) wires were realized by the acrylamide-assisted hydrothermal process using Cu(NO 3 ) 2 and thiourea (NH 2 CSNH 2 ) as reactants at 100 °C. A copper sulfide/carbon nanotube (CNTs) composite was fabricated as a similar method with the addition of CNTs. The samples are characterized by XRD, SEM, TEM, and Raman scattering spectra, respectively. The influence of reaction temperature and amine on the morphologies of CuS nanocrystals was investigated. As anode materials for sodium-ion batteries, the electrochemical studies show that the CuS/CNT composite electrode delivers a higher reversible capacity of 428.1 mA h g −1 at 0.1 A g −1 for the 100th cycle, because CNTs can be a conductive agent to provide a fast path for electron transportation, compared with the bare CuS wires (280 mAh·g −1 after 100 cycles). The synthesis results indicate that the amine-directed synthesis strategy of copper sulfide could be extended for the preparation of other metal sulfide nanostructures. Further, the incorporation of the CNT matrix into the copper sulfide is an effective approach to enhance the electrochemical performance of CuS.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
CARBON
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2024
·
IF 10.5
Rui Xue,Di Lan,Rong Qiang,Zicheng Zang,Junwen Ren,Yulong Shao,Lei Rong,Junwei Gu,Jingbo Fang,Guanglei Wu
Dielectric-dielectric nanocomposites with excellent synergistic effects are considered as a prospective avenue for the development of high-performance microwave absorbers. In this work, one-dimensional MoO 2 /Mo 2 C/C heterogeneous nanowires were synthesized via a straightforward co-precipitation and in situ pyrolysis process. The components were modulated by adjusting the reduction temperatures to achieve tunable electromagnetic parameters thereby optimizing the dielectric loss. The results showed that the optimized MoO 2 /Mo 2 C/C composite exhibited a minimum reflection loss of −50.7 dB at an ultra-thin thickness of 1.8 mm and an effective absorption bandwidth of 6 GHz at 2.3 mm when the calcination temperature was 700 °C. Based on the studies of electromagnetic parameters and radar cross section simulation outcomes, both the interwoven one-dimensional structure and synergistic effects between the components have endowed the material with good impedance matching and introduced various loss mechanisms such as conductivity loss, multiple polarization relaxation, and multiple reflection/scattering. This work presented a viable strategy for the preparation of one-dimensional MoO 2 -based dielectric microwave absorption materials.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
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2024
·
IF 5.3
Jia Zheng,Jiaxin Liu,Mingyang Ma,Ruiying Zhang,Siqi Zhang,Yun Wang,Ting Sun
Multivalent metal aqueous rechargeable batteries have great prospects in energy storage systems due to being environmentally friendly and having moderate cost. At present, the main research object of trivalent metals is aqueous aluminum-ion batteries (AAIBs). However, the high charge carried by Al3+ ions results in strong electrostatic interactions during intercalation and deintercalation of the host material. The host material structure is unstable, resulting in poor cycling performance, slow ion diffusion kinetics, and a low power output. Prussian blue analogues (PBAs) have become a promising electrode material for aqueous rechargeable batteries due to their high stability. Herein, we synthesized one-dimensional (1D) CoPBA as an innovative and high-performance cathode material for the AAIBs is reported. As a result of the unique anisotropic properties, 1D-CoPBA can provide fast axial electron transfer and short ion diffusion paths, which results in lower resistance and better contact with the electrolyte. The 1D-CoPBA cathode has a high initial discharge capacity of 100.1 mAh g–1 at 50 mA g–1 and outstanding capacity retention of 87% after 2000 cycles at 1000 mA g–1, along with an efficiency of around 100%. Assembled with 3,4,9,10-perylene tetracarboxylate diimide (PTCDI) anodes, the full battery can also deliver impressive electrochemical properties. This study provides a way to reform PBAs for high-performance cathode materials in aqueous multivalent ion batteries.
研究领域:
材料科学
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能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2018
·Vol. 10
·期 43
·20096-20107
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IF 7.233
Shuiren Liu,Xinlei Shi,Xiran Li,Yang Sun,Jian Zhu,Qibing Pei,Jiajie Liang,Yongsheng Chen
3D printing of functional inorganic nanowires has been accomplished using extruded nanowire-based inks obtained by incorporating nanofillers into polymeric matrices or thickeners. However, the presence of inactive additives poses a critical challenge for fully realizing the functionality of the nanowires in the printed structures, which remains a fundamental hurdle to overcome. Here, to construct 3D-printed electronics with high performance, we developed a versatile gelation strategy to obtain thixotropic nanowire gels through formation of dynamically stable 3D networks using small amounts of flexible, water-soluble and single-layer 2D nanosheets, such as graphene oxide and MXene, as physical cross-linkers. The nanosheets can knot-tie and stabilize the nanowire junctions in the aqueous suspension, leading to the formation of stable and thixotropic gels with viscosities up to ∼80 000 Pa s at 0.01 s−1 in the absence of polymer thickener. Gels of varioius metallic and semiconductive nanowires have been successfully prepared and printed into 3D and self-supported architectures via extrusion-based 3D-printing. The synergism of nanowires and nanosheets not only conquers the restraints of harsh post-treatments to remove additives after printing, but also maximizes the functionality of the nanowires in the printed architectures. The printed 3D structures solidified by ambient drying, coagulation, or freeze-drying exhibit remarkable functionalities. For example, the electrical conductivity of the 3D-printed silver nanowire-based architectures can reach 40 000 S cm−1. The feasibility of these functional nanowire gels was demonstrated by fabricating a series of printed flexible electronics via extrusion-based 3D-printing.
研究领域:
材料科学
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纳米技术
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电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Yangping Zhang,Fei Gao,Caiqin Wang,Yukihide Shiraishi,Yukou Du
Engineering robust electrocatalysts is always a key point in direct alcohol fuel cells. Catalysts with a one-dimension (1D) structure are well studied and considered as promising candidates among various catalysts in the past decades; however, the precise regulation on the surface structure of 1D nanomaterials is still a worthy subject. By creatively introducing a trimetallic nanoalloy, core@multishell structure, and 1D nanowire (NW) morphology, we have constructed a kind of novel spiny PtFePd@PtFe/Pt core@multishell 1D NW catalysts with PtFePd as the core and PtFe/Pt as the multishell on the basis of improving catalytic property. The composition-optimized Pt5FePd2 1D NWs display remarkable catalytic properties for ethanol oxidation reaction and methanol oxidation reaction, in which mass activities are 4.965 and 4.038 A mg–1, 4.6 and 5.0 and 4.0 and 9.2-fold higher than Pt/C and Pd/C catalysts. Furthermore, the obtained Pt5FePd2 NWs can also retain favorable stability after durability tests. The unique core@multishell structure, spiny 1D NWs with many steps and kinks, and interior electronic and synergistic effect all contribute to the advanced catalytic performance. The present work has rationally designed the novel 1D PtFePd@PtFe/Pt core@multishell NW catalysts and offered a meaningful guideline for the designing of high-performance electrocatalysts.
研究领域:
材料科学
·
电催化
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2021
·
IF 9.811
Zhongnan Guo,Fan Sun,Danilo Puggioni,Yubo Luo,Xiaotong Li,Xiuquan Zhou,Duck Young Chung,Erjian Cheng,Shiyan Li,James M. Rondinelli,Wenxia Yuan,Mercouri G. Kanatzidis
Metal cluster compounds have garnered renewed interest in the search for novel superconductors and topological semimetals owing to structural instabilities of metal-cluster geometries and broken symmetries. Here we synthesized needle-like crystals of the V-cluster-based quasi-one-dimensional (Q1D) materials AV3Q3Oδ (A = K, Rb, Cs, Q = Se, Te) which can also be viewed as being composed of parallel nanowires. We examine how changes in their average and local structure control their electronic properties. All compounds crystallize in the TlFe3Te3-type structure (P63/m space group) with infinite (V3Q3)− double-walled columnar chains separated by A+ cations. Our single-crystal and synchrotron powder diffraction studies indicate oxygen atoms partially occupy the center site of the V6 octahedral metal cluster cages in KV3Te3O0.33, RbV3Te3O0.32, and CsV3Te3O0.35, whereas KV3Se3 is structurally oxygen-free. Our synchrotron X-ray pair distribution function (PDF) analyses indicate that the oxygen-free V6 cluster octahedra in KV3Se3 are highly distorted perpendicular to the chain direction even at room temperature, reducing the symmetry of the average structure from hexagonal P63/m to monoclinic P21/m. Our theoretical calculation supports this P21/m distortion and suggests the structure further distorts to P21 or P21/c at lower temperatures. In contrast, the oxygen-centered V-cluster in KV3Te3O0.33 exhibits a V3-triangle-trimerization along the chain direction. This feature is discernible from the local PDF and is consistent with lattice dynamical calculations based on density functional theory. Resistivity measurements indicate that KV3Se3 exhibits metallic behavior, whereas a dramatic metal–semiconductor–metal transition emerges in KV3Te3O0.33, RbV3Te3O0.32, and CsV3Te3O0.35 because of oxygen disorder and changes in local structure captured from our electronic structure analyses of the Fermi surface. Our investigation of the AV3Q3Oδ family demonstrates the importance of understanding local changes in structure driven by electronic instabilities, which can guide the search for new quantum materials in other low-dimensional cluster-compound materials.
研究领域:
材料科学
·
凝聚态物理
✓ 已验证
DOI
高影响因子