CERAMICS INTERNATIONAL
·
2021
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IF 4.527
Jiaxiong Lu,Peng Dong,Yongtao Zhao,Yan Zhao,Yong Zeng
In this study, ZnO ceramics with two types of TPMS structure (Gyroid structure and Schwartz P structure) were fabricated by 3D printing . The solid content of ZnO ceramics powder was 38 wt%. The solid content of SR454NS Acrylic was 57 wt%. The other components of the slurry were photoinitiator, dispersant and sintering additive. The ZnO ceramics with high densification could be achieved after sintering at 1250 °C for 2 h. The average grain size was 37 μm and the true density of the printed ZnO ceramics was 4.95 g/cm 3 . The shape of printed ZnO ceramics can be controlled and the minimum size of thin rod is 200 μm. The compressive strength for Gyroid structural ZnO ceramic with 55% porosity and the Schwartz P structural ZnO ceramic was approximately 6.87 MPa and 4.02 MPa, respectively. The result shows that the Gyroid structural ZnO ceramics can bear much more deformation than the Schwartz P structure during the compression tests. The TPMS structural ZnO ceramics can be used in the field of sensing and detection in the future.
研究领域:
材料科学
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制造工程
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产品关联
DOI
高影响因子
Physica Status Solidi-Rapid Research Letters
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2024
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IF 2.5
Yadong Cheng,Liaoying Zheng,Huarong Zeng,Tian Tian,Xue Shi,Zhenyong Man,Xuezheng Ruan,Guorong Li,Min Zhu
Low working voltage-driven ZnO-based varistor ceramics play an important role in the multilayer chip varistors, which require a low sintering temperature of ZnO varistor for its low energy consumption. Herein, a remarkable reduction of the sintering temperature from the usual 1100–1300 °C to 950 °C is successfully achieves in the ZnO ceramics via a certain 0.05 mol% of Cr 2 O 3 dopants. The underlying mechanism is found to be involved with the formation of basal-plane inversion boundaries between the ZnO grains, which can promote the rapid grain growth within the ceramics. Furthermore, the ZnO varistors with 0.05 mol% Cr 2 O 3 dopant exhibit excellent performance. A low breakdown voltage of 416 V mm −1 , a high nonlinear coefficient of 39, and a low leakage current of 3.4 μA are obtained simultaneously. This work presents an effective and promising approach for the cost-efficient preparation of high-performance ZnO-based varistors, which have particular significance for the application of multilayer chip varistors with low working voltage.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 39
·16740-16745
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IF 0
Xuhai Li,Liang Xu,Lixin Liu,Yuan Wang,Xiuxia Cao,Yuanjie Huang,Chuanmin Meng,Zhigang Wang
ZnO ceramics with giant dielectric constants have been synthesized via a high pressure treating method. SEM results reveal that the ceramics using high pressure treated powders are porous, and the dielectric constant of the specimens first increases and then decreases with increasing density. Ceramics sintered at 1050 °C possess the optimal giant room temperature dielectric constants (∼1.8 × 104 at 100 Hz) with low relative density and dielectric loss. The improved dielectric constant can be attributed to enhanced Maxwell–Wagner poly-dispersive relaxation due to the high pressure treating process, which makes ZnO porous ceramics a potential material for high dielectric constant applications. This approach is generic and provides a new avenue to obtain porous ceramics with excellent dielectric properties.
研究领域:
材料科学
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电子材料
✓ 已验证
DOI
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
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红外隐身技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2023
·
IF 4.9
Boxu Xu,Chao Song,Jie Song,Rui Huang,Shaomin Lin,Zhenxu Lin,Yi Zhang,Dejian Hou,Jun Song
In this study, Er 3+ /Yb 3+ codoped Y 2 O 3 –ZnO ceramic phosphors were prepared by sol–gel method. The samples had two emission bands, namely, green (535 nm) and red (660 nm), which are attributed to Er 3+ : 2 H 11/2 ( 4 S 3/2 ) → 4 I 15/2 and Er 3+ : 4 F 9/2 → 4 I 15/2 radiative transitions , respectively. The samples exhibited green- and red-emission intensity enhancement by 1.728 and 2.286 times that of the pure Y 2 O 3 host, respectively and by 514.468 and 214.341 times that of the pure ZnO host. The emission intensities are first enhanced by lattice expansion. With the change of Y:Zn ratio, the high surface energy is converted into low crystal surface resulting in the change of asymmetry crystal field for matrix. When the intensity of the asymmetric crystal field reaches maximum, both emissions are further boosted. When the high surface energy transforms into crystal surface energy, the microstructure changes into a compact mesoporous structure. Consequently, the chemical stability of the samples improves significantly, and the final emission band of the three samples with mesoporous structures is continuously red.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
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IF 5.7
Meng Cao,Wen Bin Hong,Xiao Dong Yang,Xiao Jian Yan,Lei Li,Shu Ya Wu,Xiao Long Zhang,Xiang Ming Chen
The transportation of Zn 2+ in acetic acid (HOAc) or Zn(OAc) 2 water solution was considered crucial for the successful cold sintering of ZnO ceramics. However, our work shows that ZnO ceramics can even be densified by cold sintering with the aid of solid Zn(OAc) 2 ·2 H 2 O without introducing extra free water. DSC-TG analysis reveals that pure Zn(OAc) 2 ·2 H 2 O is dehydrated completely into solid Zn(OAc) 2 during heating in an open environment, while it melts in ZnO-Zn(OAc) 2 ·2 H 2 O mixture or a high-pressure and semi-closed circumstance due to the strongly suppressed dehydration. Consequently, molten Zn(OAc) 2 ·2 H 2 O acts as the transient liquid medium for the dissolution-precipitation process at over 100 °C, and plays a dominant role in the densification, microstructural evolution , and mechanical robustness of the cold-sintered ZnO ceramics. The densification mechanism is confirmed by the pressure-time curves, and reveals a novel strategy for cold sintering of water-insoluble ceramics by introducing molten hydrated salt or alkali as the transient liquid medium.
研究领域:
材料科学
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陶瓷
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烧结技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Boxu Xu,Chao Song,Jie Song,Rui Huang,Zhenxu Lin,Yi Zhang,Shaomin Lin,Jun Song
In this study, a series of well-crystallized Yb 3+ /Er 3+ /Tm 3+ -tridoped Y 2 O 3 –ZnO ceramic phosphors were prepared using sol–gel synthesis, and the phosphor structures were studied using X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis . The phosphors had excellent physical stability and porous structure. All phosphors generated blue, green, and red emission bands attributed to Tm: 1 G 4 → 3 H 6 , Er: 2 H 11/2 ( 4 S 3/2 )→ 4 I 15/2 , and Er: 4 F 9/2 → 4 I 15/2 radiative transitions , respectively. The emissions were intensified twice by tuning the Tm 3+ ratio in the host matrix Y 2 O 3 and ZnO parts. The color coordinates were adjusted by tuning both the Tm 3+ concentration and the excitation laser pump power to shift the color coordinates and only enhance the brightness, respectively. Meanwhile, heating phosphors can also linearly adjust the color coordinates of the luminescence. Therefore, it can also be used as a fluorescence thermometer in the field of temperature sensor . The study findings will broaden the phosphor practical application potential.
研究领域:
材料科学
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光学
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陶瓷
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发光材料
·
温度传感
✓ 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）