CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Jingwei Chen,Xinqiang Wang
Three kinds of Gd 2 Zr 2 O 7 /ZrO 2 (GZC) composite fibers with different proportions of Gd 2 Zr 2 O 7 were prepared by electrospinning method through changing the amount of Gd 3+ in precursor solutions. The thermal decomposition, crystallization process , high temperature stability and heat-conducting properties of GZC fibers were fully characterized. The results showed that there were three crystalline phases, tetragonal phase ZrO 2 , cubic phase ZrO 2 and defect fluorite phase Gd 2 Zr 2 O 7 in all the GZC fibers. The content of Gd 2 Zr 2 O 7 increased gradually with the increase of Gd 3+ in precursor solutions which led to the gradual slowing down of grain growth rate, the decrease of thermal conductivity and the increase of high temperature stability of the obtained composite fibers. The thermal conductivities of all the GZC fiber sheets were lower than that of 7YSZ fiber sheet. The sheets of all the GZC fibers could keep the high temperature stability up to 1300 °C.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2021
·
IF 3.423
Antuo Wang,Xianglong Li,Teng Hou,Yishen Lu,Jing Zhou,Xianggui Zhang,Bin Yang
In order to solve the problem of air pollution, especially in high temperature environment, an ultrafine poly(tetrafluoroethylene) (PTFE) porous fibrous membrane (UPPFM) was created by electro-centrifugal spinning, sintering calcination and impregnation technology in this paper. The pores distribution on the surface of the fibers could be simply controlled by adjusting PVP/PTFE ratios, and prompted the porosity of obtained membrane up to 94.1%. The obtained membrane presented an ultralow air resistance to 89.9 Pa with filtration efficiency higher than 99.72%. Moreover, UPPFM showed excellent heat stability and reusability, and therefore exhibited a great potential application in the high temperature air filtration.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xinlei Jia,Zihan Zhou,Donghui Guo,Baolu Shi,Ning Zhou,Baosheng Xu
Polymer-derived ceramic aerogels are promising materials for thermal insulation and microwave absorption in harsh environments because their microstructures can be controlled at the molecular level. Silicon oxycarbide (SiOC) aerogels are considered as potential high-temperature electromagnetic wave (EMW) absorbers, but their application range is limited by complex preparation process and unsatisfactory microwave-absorption performance. This paper reports a new SiC nanowire/SiOC composite aerogel (SCA) synthesized through the sol–gel process, environmental pressure drying, and high-temperature treatment. The SCA performance is adjusted by controlling the ratio of SiC nanowires, obtaining low thermal conductivities (0.04–0.042 W m −1 K −1 ) and excellent mechanical properties (4.37–5.45 MPa). Increasing the SiC nanowire content gradually increases the EMW absorption capacity of SCA. The optimal reflection loss is −53.64 dB and the effective absorption bandwidth is 3.88 GHz, substantially higher than that of SiOC aerogels . This high performance is mainly attributable to the appropriate impedance matching characteristics and strong polarization loss ability. Moreover, the performance of the composite aerogels was retained after long-term treatment in an air environment at 800 °C. SCA also exhibits excellent high-temperature insulation and flame retardancy. Owing to its light weight, strong microwave-absorption ability, good thermal insulation performance, and oxidation resistance , SCA is a highly promising alternative material for use in extreme environments.
研究领域:
材料科学
·
复合材料
·
热能工程
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Junpeng Jiang,Liwen Yan,Jiangtao Li,Yunjia Xue,Chensi Zhang,Xiaoxia Hu,Anran Guo,Haiyan Du,Jiachen Liu
Owing to tunable dielectric properties, light weight and high porosity, polymer-derived SiBCN ceramic aerogels possess significant application prospects in electromagnetic wave (EMW) absorption and thermal insulation. However, due to inadequate oxidation resistance, the structural collapse and performance deterioration of SiBCN aerogels will easily occur in high-temperature aerobic environments, limiting their application. Herein, to address this issue, a novel and straightforward strategy based on typical polymer-derived-ceramic (PDC) aerogel method and impregnation with boehmite sol was proposed for synthesizing SiBCN/Al 2 O 3 composite ceramic aerogels. The microstructure, phase composition, thermal insulation, oxidation resistance and EMW absorption properties of SiBCN/Al 2 O 3 ceramic aerogels were investigated. The resulting SiBCN/Al 2 O 3 composite aerogel demonstrates superior high-temperature structural stability, exhibiting an ultra-low linear shrinkage of only 6.5 % following heat treatment at 1200 °C for 2 h in air. Additionally, the composite aerogel shows a low thermal conductivity of 0.039 W/mK and a low density of 0.112 g/cm 3 . The SiBCN/Al 2 O 3 composite aerogel, composed of dielectric SiBCN, conductive free carbon, and insulating alumina, demonstrates outstanding EMW absorption properties with a minimum reflection loss of −48.6 dB and an effective bandwidth of 5.8 GHz. The enhanced microwave absorption performance is mainly attributed to the improved impedance matching, multiple reflection, and enhanced interfacial polarization resulting from the introduction of Al 2 O 3 . Given prominent oxidation resistance, thermal insulation and EMW absorption properties, the SiBCN/Al 2 O 3 composite aerogel paves the way for developing microwave absorption and thermal insulation integrated material in high-speed vehicles.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Qingguo Chi,Zhiyou Gao,Tiandong Zhang,Changhai Zhang,Yue Zhang,Qingguo Chen,Xuan Wang,Qingquan Lei
In recent years, polymer-based dielectric capacitors have attracted much more attention due to the advantages of excellent flexibility, light weight, and high power density. However, most studies focus on energy storage performances of polymer-based dielectrics at room temperature, and there have been relatively fewer investigations on polymer-based dielectrics working under high-temperature conditions, which is much closer to the practical applications. Besides, dielectric capacitors operating in a high-temperature environment require excellent temperature stability of structure and performance. In this paper, high-temperature-resistant polyimide (PI) is selected as the matrix material, and 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BZT–BCT) nanofibers are used as the filling phase. By analyzing the energy storage behaviors of BZT–BCT/PI composites at different temperatures, it can be found that when the doping content of BZT–BCT nanofibers is more than 1 vol % the dielectric strength of the composites drops sharply when the temperature increases from 25 to 150 °C, resulting in serious deterioration of energy storage properties. On the basis of this, a composite film with a sandwich structure has been designed, where BZT–BCT/PI with different volume fractions is the intermediate layer and hexagonal boron nitride (h-BN) with good thermal and insulating properties is introduced in the top and bottom layers with a content of 5 vol %. Consequently, the results have shown that the energy storage properties of the constructed sandwiched dielectric composite films exhibit excellent temperature stability. The maximum field strength of the composite film with a BZT–BCT content of 1 vol % in the intermediate layer is 360 and 350 kV/mm under temperatures of 25 and 150 °C, and the storage density is 2.3 and 1.83 J/cm3 respectively.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Chen Zhang,Xin Wang
In this paper, CaO-B 2 O 3 -SiO 2 (CBS) is utilized as matrix material of microwave coating for the first time to achieve high-performance microwave absorption under high-temperature. A series of FeSiAl (FSA)/CBS composite coatings were prepared via atmospheric plasma spraying. The impact of spraying power on the microstructure, electromagnetic properties, and high-temperature stability of as-sprayed coatings were studied. The experimental results reveal that CBS could effectively suppress the formation of the lamellar structure of FSA as the low initial melting temperature, also form unexpected Fe 2 SiO 4 structure with FSA during the spraying process. The increase in complex permittivity of the coating is primarily attributed to enhanced coating density and the development of Fe-rich regions within the CBS matrix. Furthermore, the dense coating prevents the oxidation of FSA and exhibits high-temperature stability. Our coating of 1 mm thickness has a reflection loss below -5 dB with frequency range of 7–14.8 GHz at 500 °C.
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
·
2020
·
IF 6.182
Yulin He,Ying Li,Yaochun Liu,Nianchun Yao,Jiamei Li,Yang Liu
Inspired by the WO 3 transition metal semiconductor, a simple liquid phase WO 3 coating strategy is introduced to improve the surface stability of LiNi 0.5 Co 0.2 Mn 0.3 O 2 . The electrochemical performance of WO 3 -coated LiNi 0.5 Co 0.2 Mn 0.3 O 2 is improved at both a high cut-off voltage (4.5 V) and high temperature (50 °C). With the WO 3 (0.6 wt%) coating amount optimized, the material capacity retention is maintained at 138 mAh g −1 and 170.9 mAh g −1 at 25 °C and 50 °C after 200 cycles compared with 107.8 mAh g −1 and 143.9 mAh g −1 , respectively, for pristine NCM523. The WO 3 -coated sample also exhibits a better rate capability, maintaining 126 mAh g −1 at 25 °C in the voltage range of 3–4.5 V at the current density of 5 C. The enhanced properties of the WO 3 -coated LiNi 0.5 Co 0.2 Mn 0.3 O 2 due to the WO 3 coating layer result from the interface that prevents immediate contact between the electrolyte and the active material as well as the lower polarization and electrochemical resistance of the battery. SEM, TEM, XPS and EIS further reveal these improved electrochemical performances, which indicate the success of the approach for regenerating NCM523.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2023
·Vol. 25
·期 39
·5533-5540
·
IF 3.1
Xu Zhang,Shenghui Han,Gang Lian,Deliang Cui,Qilong Wang
Matrix- and metal-free phosphorescence materials with long room-temperature lifetime and high-temperature phosphorescence properties have attracted tremendous attention but seldom reported. Herein, a universal fluorination strategy was proposed to obtain a series of matrix-free fluorinated boron nitride dots (F-BNDs) with markedly extended lifetime by constructing rigid F-induced hydrogen-bond networks. Miraculously, when the F-BNDs(e) were heated to 150 °C, the afterglow was temperature-controlled and still maintained with a lifetime as long as 0.25 s. In terms of their interesting phosphorescence properties, this work actually provides a guiding strategy to realize F-BND phosphorescence materials with time-resolved and temperature-controlled lifetime encoding characteristics. Widespread applications in higher-level information encryption, time-resolved information displaying, dynamic multidimensional anti-counterfeiting and colorless security ink were demonstrated.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2024
·
IF 2.3
Gao Shuai,Han Meixu,Pan Jinwen,Zhong Yang,Jiang Hongyi
Silica aerogel (SA) was synthesized through the sol-gel process followed by ambient pressure drying, with aluminum-deposited silica aerogel (ASA) subsequently produced via aluminum deposition using an AlCl 3 ·6H 2 O hydrolysis solution. This study examined the impact of deposition time and calcination temperature on ASA’s characteristics. Compared to the non-aluminum-deposited SA, ASA with 12 h of deposition time (ASA-12h) showcased a significant increase in specific surface area, reaching 675m 2 ∙ g −1 at room temperature. Post-calcination at 800 °C and 1000 °C resulted in specific surface areas of 613m 2 ∙ g −1 and 265m 2 ∙ g −1 , respectively, markedly surpassing those of SA (240 m 2 ∙g −1 at 800 °C and 16m 2 ∙ g −1 at 1000 °C). The results demonstrate that during the aging process, the deposited aluminum is coated by the aging solution, enabling it to remain stable and distribute uniformly. This deposition not only increases the particle size but also enhances structural stability. Furthermore, the formation of new Si-O-Al bonds improves the thermal stability of the silicon dioxide lattices. These insights pave the way for the industrial production of aerogels that are resistant to high temperatures. Graphical Abstract
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Biao Zhang,Shuhang Yu,Qiantong Li,Zhihong Luo,Wangxin Li,Mingmei Lin,Junhui Lang,Mingwang Yuan,Jianming Deng,Feng Yan,Changbai Long,Dawei Wang,Laijun Liu
Next-generation jet engines, metal forging processes, and non-destructive monitoring of nuclear power plants demand piezoelectric sensors with ultra-high operating temperature, exceptional sensitivity, and outstanding temperature stability. Bismuth calcium niobate (CaBi 2 Nb 2 O 9 , CBNO) is considered a candidate for high-temperature piezoelectric materials due to high-Curie temperature ( T C ) near 900 °C. However, pure CBNO shows a poor piezoelectric coefficient ( d 33 ) and low high-temperature resistivity ( ρ ). In this work, the piezoelectricity, ferroelectricity, and resistivity of CBNO ceramics were significantly improved by constructing pseudo-tetragonal boundary through the co-substitution of Li/Ce at A site and W/Mo at B site. Remarkably, Ca 0.92 (Li 0.5 Ce 0.5 ) 0.08 Bi 2 Nb 1.97 (W 2/3 Mo 1/3 ) 0.03 O 9 (CLCBN-3WM) ceramic exhibits the best performance: ultra-high T C (∼ 922 °C), very high d 33 (∼ 16.1 pC/N), a large remanent polarization (∼ 11.61 μC/cm 2 ), and very good high-temperature insulation ρ (∼ 7.4 × 10 5 Ω·cm at 600 °C), as well as excellent thermal stability with its d 33 value degeneration from 16.1 pC/N to 15.1 pC/N from room temperature to 800 °C (less than 7.0 %). These results indicate that CLCBN-3WM ceramics have significant potential for using in electromechanical transducers operating at high temperatures (600 °C or higher).
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·Vol. 13
·期 1
·456-464
·
IF 5.7
Xiaoman Zhang,Yehua Zheng,Kun Nie,Xiaodong Zhang,Xiuqiang Duan,Ziyao Hu,Ming Yang,Lefu Mei,Luoxin Wang,Hua Wang,Mingquan Li,Xiaoxue Ma
Lead-free double perovskites are environmentally friendly, and their good photoelectric efficiency has received widespread attention. However, the stability and efficiency of lead-free perovskites need to be further improved to meet the growing application needs. In this study, thermally quenched perovskite (Cs2NaHoCl6) crystals (PCs) were successfully synthesized by co-precipitation. By doping with Sb3+, the excitation wavelength of the original perovskite increased significantly to 250–360 nm, and the emission wavelength of the original perovskite also increased significantly to 660 nm. Cs2NaHoCl6:Sb3+ PCs are made of red and white light-emitting diodes (LEDs) for general lighting applications. In addition, Cs2NaHoCl6:Sb3+ PCs are made into flexible luminescent fibers with aramid/polyphenylene sulfide (ACFs/PPS) composite fibers. Based on the good thermal quenching resistance of Cs2NaHoCl6:Sb3+ PCs, the flexible luminescent fibers showed excellent high-temperature luminescence stability. At 125 °C, flexible luminescent fibers retained 99.8% of the original luminescence intensity; at 250 °C, they retained 75.6% of the original. These flexible luminescent fibers have the potential to be used in fluorescence detection in high-temperature environments. In summary, this study used a simple method to prepare lead-free perovskites with good optical properties and stability, expanding the application of perovskites in the field of fibers.
研究领域:
材料科学
·
光学工程
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yong Zhang,Yuchang Qing,Junjie Yang,Chuanyang Jiang
SiC, with outstanding oxidation stability and tunable dielectric property, has been regarded as a promising microwave absorption material for high-temperature applications. However, the application of pristine SiC is restricted by its inadequate dielectric response and weak loss capability. Herein, a novel strategy is proposed to construct Cr-Si-C conductive shell on SiC surface via molten salt method is proposed to introduce heterogeneous interfaces and enhance dielectric loss. The optimal SiC@Cr-Si-C core-shell sample achieves a minimum reflection loss (RL m ᵢ n ) of −36.7 dB at a matching thickness of 1.4 mm. Meanwhile, it exhibits an effective absorption bandwidth (EAB) of 2.41 GHz. Notably, even after heat treatment at 600 °C in air for 5 h, the core-shell absorber maintains an intact core-shell structure and its RL m ᵢ n remains as high as −34.4 dB, demonstrating superior high-temperature stability. This work provides an effective method for high-performance microwave absorption materials targeted at high-temperature applications.
研究领域:
材料科学
·
电磁功能材料
·
介电材料
·
高温材料
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子