JOURNAL OF ALLOYS AND COMPOUNDS
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2021
·
IF 5.316
Lingjie Li,Zhonghao Ning,Wenyan Huang,Liang Liao,Yinong Zheng,Kun Zhuang,Siqi Lan,Yinggan Zhang,Rongqian Yao
An ingenious strategy to prepare in-situ formed SiC(Al, rGO) bulk polymer-derived ceramics (PDCs) from re-pyrolyzing SiC(Al, rGO) p /polyaluminocarbosilane-vinyltriethoxysilane-graphene oxide (PACS-VTES-GO, PAVG) blends is highlighted. Flexible PAVG modified by Al with highly cross-linked structure effectively improves molecular weight and formability of precursors. Rigid SiC(Al, rGO) p fillers provide high mechanical properties owing to their unique microstructure which is consistent with SiC(Al, rGO) bulk PDCs. β-SiC nanocrystals are well dispersed in amorphous SiO x C y /C free , and rGO exhibits good compatibility with SiO x C y /C free . Besides, possible Al 2 O 3 is beneficial to relaxing thermal stress at β-SiC nanocrystalline boundaries. Interestingly, introduction of Al could avoid coarsening of β-SiC grains to enhance elevated temperature resistance. Furthermore, effect of re-pyrolysis temperature on the formation and microstructure of SiC(Al, rGO) bulk PDCs was also investigated. Particularly, lightweight samples re-pyrolyzed at 1300 °C display optimal fracture toughness (3.32 MPa m 1/2 ), compressive strength (177.16 MPa) and flexural strength (51.25 MPa), high ceramic yield (94.46%) and low linear shrinkage (4.38%), by far superior to those of most PDCs. As treated via precursor infiltration and pyrolysis (PIP) route and heated by butane gun flame in air, such products possess stable structures under elevated temperatures and have potential emerging uses in aerospace components.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2017
·Vol. 82
·期 3
·718-727
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IF 1.575
Wei Heng-yong,Li Hui,Cui Yi,Sang Rong-li,Wang He-yang,Wang Peng,Bu Jing-long,Dong Gui-xia
Abstract Mullite nanofibres with excellent flexibility and high temperature resistance were fabricated by electrospinning method using the nonhydrolytic sol as a precursor. The nonhydrolytic mullite sol exhibited favourable organosolubility and spinnability, due to the residual organic groups in gel particles. The thermal decomposition behaviour, crystallisation development and microstructure evolution of electrospinning precursor fibres were investigated. Results showed that the flexible mullite nanofibres with smooth surface, uniform diameter and small crystal grain size were obtained after the precursor fibres were calcined at 1000 °C for 1 h. In addition, the results also revealed that the mullite nanofibres calcined at 1500 °C still maintained their general fibrous morphology, and thereby they had the potential application in high-temperature industrial and aerospace field. Graphical Abstract
研究领域:
材料科学
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无机化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
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IF 9.229
Tao Huang,Ying Pan,Chunfeng Yan,Maoxiang Wu
In this work, we propose that 1,1,3,3-tetramethyldisiloxane (TMDS) is beneficial for electrochemical property enhancement of LiNi0.5Mn1.5O4/Li cells at high temperatures. The LiNi0.5Mn1.5O4/Li cells with 1 vol % TMDS revealed capacity retention of 81.2% after a cycling test at 55 °C, while the cells without additive showed capacity retention of only 32.3%. The cells with 1 vol % TMDS also presented a better rate performance, reaching 100 mAh g–1 under 3C. Physical characterization and theoretical calculations revealed that TMDS formed a thinner and better conductive layer on the LiNi0.5Mn1.5O4 surface and effectively scavenged HF/F– from the electrolyte, contributing to high stabilization of LiNi0.5Mn1.5O4.
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
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2021
·Vol. 105
·期 1
·181-192
·
IF 3.784
He Li,Yongsheng Liu,Paolo Colombo,Wenbo Li,Yansong Liu,Kehui Hu,Zhigang Lu
3D-printed alumina ceramic cores often face the problem of low flexural strength at its application temperature of 1500℃, and the requirements on porosity and strength limit its fabrication process. In this research, three types of solutions were employed to impregnate the ceramics to improve the strength of the 3D-printed alumina ceramic cores. The results showed that silica sol (SS), tetraethyl orthosilicate (TO), and 3-(Trimethoxysilyl)propyl methacrylate (PM) all could improve the (room temperature) flexural strength of the 3D printed ceramics effectively compared to the control sample (CS) without impregnation, and the SS solution could improve the high temperature flexural strength at 1500℃ greatly compared to other solutions. The improvement in strength was due to the introduction of Si, which formed a stable mullite phase during the sintering process. Computed tomography (CT) analysis showed there is no cracks formed in the ceramic cores impregnated with the SS solution, and they exhibited the overall best performance (21.2 ± 0.8 vol% open porosity, shrinkage of 3.2 ± 0.3% in the X direction, 3.4 ± 0.2% in the Y direction, 2.1 ± 0.4% in the Z direction, room temperature flexural strength of 85.7 ± 6.9 MPa, and 1500℃ flexural strength of 19.2 ± 1.1 MPa).
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yiding Li,Qiang Zhang,Simin Shen,Siqi Wang,Liangliang Shi,Dequan Liu,Yujun Fu,Deyan He
Effectively limiting the shuttle effect is the key to improving the electrochemical performance of Li-S batteries. Here, the synthesis of WO 3 -WS 2 heterostructures is reported by electrospinning and in situ sulfurization strategies, combining the initial WO 3 nanoparticles with the sulfurization product WS 2 . It was found that the obtained bifunctional heterostructures enhance the electrolyte wettability, optimize intermediate regulation performance, accelerate Li + /e − diffusion, and thus exhibit excellent electrochemical characteristics in Li-S batteries. Through experiments and density functional theory (DFT) calculations, the WO 3 -WS 2 heterostructures were considered as a coupled creative solution with multiple advantages. Different from the batteries using single-component or single-configuration catalyst, the prepared Li-S batteries with the WO 3 -WS 2 heterostructures exhibited synergistic enhanced electrochemical performance and high-temperature crushing resistance. Even under severe conditions, including high sulfur loading (10.3 mg cm −2 ), lean electrolyte (5.8 μL mg −1 ), high current density (7.0 A g −1 ), extended cycling (1600 cycles), and high temperature (90 °C), the representative battery exhibited stable cycling performance.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Energy & Environmental Materials
·
2024
·
IF 13
Yongbin Liu,Yating Xu,Jinghui Gao,Jingzhe Xu,Ming Wu,Zhengwei Liu,Yilong Wang,Xiaojie Lou,Lisheng Zhong
High-temperature performance of energy storage dielectric polymers is desired for many electronics and electrical applications, but the trade-off between energy density and temperature stability remains fundamentally challenging. Here, we report a general material design strategy to enhance energy storage performance at high temperatures by crosslinking a polar polymer and a high glass-transition temperature polymer as a crosslinked binary blend. Such crosslinked binary polymers display a temperature-insensitive and high energy density behavior of about 6.2 ~ 8.5 J cm −3 up to 110 °C, showing a significant enhancement in thermal resistant properties and consequently outperforming most of the other ferroelectric polymers. Further microstructural investigations reveal that the improved thermal stability stems from the confinement effect on conformational motion of the crosslinking network, which is evidenced by the increased rigid amorphous fraction and steady intermolecular distance of amorphous regions from temperature-dependent X-ray diffraction results. Our findings provide a general and straightforward strategy to attain temperature-stable, high-energy-density polymer-based dielectrics for energy storage capacitors.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
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2024
·
IF 7.4
Guolan Dou,Chen Wang,Xiaoxing Zhong,Botao Qin
In this study, lignin modified cementitious materials (LFGS) were synthesized to determine the viability of mineral cementitious sealing and firefighting materials using uncalcined coal gangue (UCG) and fly ash (FA) as raw materials in order to realize the resource utilization of coal-based solid waste and prevent spontaneous combustion of coal gangue and coal fires. The 28-d compressive strength was increased to 63 MPa, the fluidity was improved to 142 mm, and the final setting time was shortened to 75 min with 0.1 wt% lignin. Thermal exposure experiments demonstrated that lignin modification could improve the high temperature resistance in terms of residual compressive strength , thermal crack and shrinkage resistance. The microstructure and thermogravimetric characterization of the resulting cementitious materials revealed the generation of a dual-crosslinked network composed of covalent linkages (Si-O-Al bonds) and hydroxyl groups-Ca 2+ coordination bonds. The average air sealing efficiency of LFGS was found to be 53.7% higher than that of ordinary Portland cement slurry. The examination of the CO 2 emissions of the cementitious materials revealed that the carbon emission index of LFGS was approximately 55% lower than that of ordinary Portland cement . This study not only presents a resource utilization strategy for uncalcined coal gangue and coal fly ash, but also a green and low carbon emission cementitious firefighting material to prevent coal fires.
研究领域:
材料科学
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环境科学
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矿业工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2024
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IF 8.1
Lingzhi Nie,Jingyu Lin,Pengtu Zhang,Peiyuan Zuo,Xiaoyun Liu,Qixin Zhuang
In the field of electrostatic energy storage, polymers exhibit notable advantages, including high breakdown strength (E b ) and fast charge/discharge rates. However, at elevated temperatures, their discharge energy density (U d ) decreases due to reduced E b and increased electrical conductivity losses. We herein integrate fluoro-functionalized polyimide (PFI) shell-modified Al 2 O 3 nanoparticles (PFI@Al 2 O 3 ) with polyetherimide (PEI) to form a trap-rich electrostatic crosslinked network. By energy level modulation and electrostatic crosslinking, the PFI layer enables to capture charges and acts as crosslinking sites, while the wide-bandgap Al 2 O 3 introduces energy barriers that inhibit charge injection and migration. This sophisticated dual-interface design enhances E b and facilitates dual capture of electrons and holes, thus effectively reducing leakage current and conduction losses. Surprisingly, the composites prepared using this method exhibit an energy density of 7.24 J/cm³ at 150 °C, with a charging-discharging efficiency of 83.58 %. Moreover, it maintains stability even after 10 5 extended charge-discharge cycles under harsh conditions (200 kV/mm and 150 °C). This work lays a solid foundation for electrostatic energy storage at elevated temperature.
研究领域:
材料科学
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能源工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Hengjia Zhang,Tengchao Guo,Litao Lin,Bin Quan,Xiaohui Zhu,Xiaogu Huang
High temperature material with low infrared emissivity in 3–5 μm waveband plays a crucial role in the infrared stealth capability of hot-end aircraft components. In this study, 3 mol% Ce doped ZnO ceramic powders were annealed at various temperatures to reduce their infrared emissivity. The effects of the annealing temperature on the lattice structure, microscopic morphology, and elemental valence variation in the ZnO ceramic powders were systematically investigated. Additionally, a conductivity–dielectric–lattice vibration synergy theory was proposed to provide insights about the changes in the infrared emissivity of the ZnO ceramic powders. The infrared emissivity of the sample powder gradually decreased to its lowest value (0.092 at 500 °C) as the annealing temperature increased to 1100 °C, exhibiting a U-shaped curve from room temperature to 800 °C. Furthermore, the obtained powder was used as a filler to prepare a low infrared emissivity coating, which exhibited an infrared emissivity of 0.213 in 3–5 μm waveband at 500 °C. An infrared thermographic analysis of the coating indicated that it significantly suppressed infrared radiation at 500 °C, demonstrating an excellent high temperature infrared stealth performance.
研究领域:
材料科学
·
红外隐身技术
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yucong Liao,Shengqiu Zhao,Guoliang Liu,Hao Li,Jiaqi Shuai,Letian Wang,Bingxuan Liu,Haolin Tang
Proton exchange membrane fuel cells (PEMFCs) face a significant challenge when operating in high-temperature and low-humidity environments, the hydrocarbon-based polymers that are sulfonated or phosphonated can’t meet the demand for achieving high performance. Modifying perfluorosulfonyl fluoride (PFSF) through meticulous design of side-chain chemical structures and introducing functionalized sulfonimide and phosphonic acid groups. Membranes derived from a perfluorocarbon backbone and polyacid side chain structures exhibit distinct microphase separation. The sulfonimide group exhibits hyper-acidic properties, whereas the phosphonic acid group functions as proton acceptor and donor. These two groups work synergistically to establish a distinct proton transport channel. The robust adsorption between acidic functional groups and water molecules enhances the diffusion of water molecules, resulting in an increase in proton conductivity. Moreover, Density Functional Theory (DFT) calculations reveal that the phosphonic acid group of the side chain has difficulty forming anhydrides. The prepared perfluorosulfonimide-phosphonic acid (PFSNPA) proton exchange membrane demonstrates an impressive conductivity of 263 mS·cm −1 at 120 °C. In H 2 /Air fuel cell tests, PFSNPA achieves an outstanding output power of 1076.1 mW·cm −2 at 120 °C and 40 % RH. This study introduces a new approach for designing and fabricating proton exchange membrane materials for high-temperature fuel cells.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2025
·
IF 4.3
Zeren Kang,Wei Wang,Jinhai Xu,Xiaoji Zhou,Shusu Shen,Renbi Bai
The poor thermal stability of polyvinylidene fluoride (PVDF) membranes and their tendency to swell in organic solvents limit their widespread application in the field of membrane technology. In this study, the fluorinated polyimide (FPI), P(6FDA-BAPOFP), was investigated for the first time as a modifier for the PVDF membrane to enhance its stability at high temperatures and in organic solvents. By leveraging the inherent affinity between the C-F bond in FPI and PVDF, the compatibility of the physical blending has been significantly improved. The optimal addition of 2.5 % FPI led to a 2.0-fold increase in flux while preserving rejection. The introduction of FPI into the membrane effectively delayed the thermal weight loss, demonstrating stable performance in 90 °C water. In particular, after an operational period of up to 12 days, the modified membrane exhibited > 80 % Congo Red rejection and relative stable permeance (85 L·m −2 ·h −1 ·bar −1 ). This high-flux polymer membrane contributes to energy conservation and emissions reduction in industrial production.
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Jiabin Ma,Yuping Duan,Ning Zhu,Hanxiao Jia,Naibo Wu,Huifang Pang
Traditional EMI shielding materials encounter significant problems, including pyrolytic deformation, oxidation and reduced performance at high temperatures. Perovskite oxide ceramics, with non-oxidizing properties and increasing conductivity with rising temperature, offer solutions. To address these issues, high-entropy perovskite cobaltate ceramics (Y 0.2 La 0.2 Sm 0.2 Nd 0.2 Gd 0.2 )CoO 3 (HE RECoO 3 ) were designed and synthesized via a straightforward one-step solid-state reaction. These ceramics exhibit unique transport properties due to the high-entropy effect, multivalent Co ions, and high defect concentration. The resulting dielectric-conductive synergy enables microwave absorption and wide-temperature-range EMI shielding compatibility, alongside thermoelectric conversion capabilities. Specifically, treating HE RECoO 3 at 1200 °C for 2 h shows a reflection loss of up to −62.60 dB at 25 °C and SE values >30 dB across the entire X-band at 500 °C, and a Seebeck coefficient of 53.56 μV/K. This simple, cost-effective synthesis process makes HE RECoO 3 ideal for wide-temperature-range EMI shielding applications.
研究领域:
材料科学
·
电磁学
·
无机化学
·
热电材料
✓ 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）