MATERIALS RESEARCH BULLETIN
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2024
·
IF 5.3
Kang Du,Zheyu Liu,Changzhi Yin,Yiyang Cai,Mengdie Zhou,Tailai Wen,Wei Zhu,Cai Zhou,Weijia Han,Shengxiang Wang,Wen Lei
Novel Ba 2 RE 2 Si 4 O 13 ( RE = La, Nd, Sm, Eu, Gd, Ho, Er and Yb) ceramics were prepared by traditional solid reaction methods. The phase compositions of Ba 2 RE 2 Si 4 O 13 ceramics were explored. The triclinic structure with P 1 ¯ space group of Ba 2 RE 2 Si 4 O 13 ceramics was confirmed by TEM and Rietveld refinement analyses, and the decrease in the ionic radius of RE 3+ induced the phase transition from low symmetry (triclinic) to high symmetry (monoclinic) between Ba 2 Sm 2 Si 4 O 13 and Ba 2 Eu 2 Si 4 O 13 . ε r-exp of the Ba 2 RE 2 Si 4 O 13 ceramics was significantly affected by ionic polarisability. The ‘rattling and compressing effects’ of cations also affected the ε r-exp of Ba 2 RE 2 Si 4 O 13 ceramics. The intrinsic dielectric loss of Ba 2 RE 2 Si 4 O 13 ceramics were evaluated by the far-IR reflectivity spectrum, and high Q × f values of the Ba 2 Nd 2 Si 4 O 13 and Ba 2 Eu 2 Si 4 O 13 ceramics were attributed to their large total lattice energy and activation energy. The average bond valence of RE 3+ played an important role in controlling the τ f values of the Ba 2 RE 2 Si 4 O 13 single-phase ceramics, and the high average bond valence of RE 3+ corresponded with the small negative τ f values. Great microwave dielectric properties ( ε r = 11.52, Q × f = 33,600 GHz at 11.80 GHz and τ f = ‒25.6 ppm/ °C) were obtained in the Ba 2 Nd 2 Si 4 O 13 single-phase ceramic.
研究领域:
材料科学
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物理学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Manting Zeng,Xingzhong Liu,Hua Hao,Zhonghua Yao,Hanxing Liu
BaTiO 3 -1.6MnO 2 - x Er 2 O 3 ceramics (abbreviated as BMT- x Er) and BaTiO 3 -1.6MnO 2 -3Er 2 O 3 - x MgO ceramics (abbreviated as BEMT- x Mg) were prepared under a reducing atmosphere by solid-state synthesis method in this work. The effects of Er/Mg co-doping on phase transformation, microstructure, dielectric properties, and defect were systematically investigated. Research shows that Er-doping reduces the Curie temperature and increases the dielectric constant of BaTiO 3 ceramics at low temperatures. Mg-doping refines the grain size and makes the grain size distribution more uniform, which is an important reason for the enhanced bias stability. The substitution of Mg at the B-site generates additional oxygen vacancies which capture free electrons and simultaneously forms defect dipoles. The anti-reducing properties are improved by reducing the carrier concentration. The synergistic effect of co-doping forms defect dipoles such as [ Mg Ti ″ ‐ 2 Er Ba ∙ ] , [ Mg Ti ″ ‐ V O ∙ ∙ ] and [ 2 Er Ti ′ ‐ V O ∙ ∙ ] to enhance dielectric relaxation behavior which is considered to be the reason for the improved dielectric temperature stability. When x = 0.4, optimized dielectric ceramics are obtained with ε 25°C = 1820, tanδ = 0.009, resistivity of 1.0 × 10 11 Ω·cm, which meets the EIA X7R standard (−55 °C - 125 °C, TCC ≤ ± 15 %).
研究领域:
材料科学
·
电子工程
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产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2012
·Vol. 95
·期 11
·3525-3531
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IF 2.272
Guofeng Yao,Xiaohui Wang,Yichi Zhang,Zhengbo Shen,Longtu Li
0.9BaTiO 3 –0.1Bi 0.5 Na 0.5 TiO 3 -based (0.9BT–0.1BNT) ceramics with T c = 180°C were prepared using a novel chemical coating method. The relationships among compositions, microstructures, and properties were investigated. TEM morphologies displayed the Nb-coated powders, which were confirmed by energy dispersive spectroscopy (EDS). Temperature-dependence of permittivity for Nb-modified 0.9BT–0.1BNT ceramics measured at different frequencies showed no relaxor characteristic at high temperature, but frequency dispersion at low temperature. The microstructures were characterized by two types of grains: Nb-rich grains and Nb-free grains, which were responsible for temperature-stable dielectric properties. The sample with 5 mol% Nb addition satisfied the X9R specification. The permittivity was 1934 and the dissipation factor was 1.53% at room temperature.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·
IF 2.605
J.C. Wang,P. Zheng,R.Q. Yin,L.M. Zheng,J. Du,L. Zheng,J.X. Deng,K.X. Song,H.B. Qin
Four groups of barium titanate (BaTiO 3 ) ceramics with high piezoelectric coefficient have been successfully fabricated from different raw materials. Their average grain size ( g ) dependences of the piezoelectric coefficient d 33 were systematically studied. It was found that for two groups of BaTiO 3 ceramics, d 33 firstly increases and then decreases with the increase of g , with a maximum d 33 of 449 pC/N and 501 pC/N respectively at approximately 1 µm grain size, while for the other two groups of BaTiO 3 ceramics, d 33 keeps increasing with the increase of g . The highest d 33 of 401 pC/N and 424 pC/N were obtained when g is larger than 50 µm. The experimental results indicated that piezoelectric grain size effect in BaTiO 3 ceramics may be not absolute. Possible mechanisms arising from differences in domain configuration were discussed.
研究领域:
材料科学
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物理学
✓ 已验证
产品关联
DOI
高影响因子
FERROELECTRICS
·
2015
·
IF 0.469
Y Feng,W. L. Li,D. Xu,W.D. Fei
Ba(1-2x)LixAlxTiO3 (x = 0, 0.5, 1.5 and 2.5 mol%) ceramics were prepared by a conventional sintering method. The effects of Li+ and Al3+ content on the crystalline structure, dielectric and piezoelectric properties of BT ceramic were investigated. A better incorporation of Li+ and Al3+ ions recently occurs in our system without any impurity at x≤1.5 mol%. Ba(1-2x)LixAlxTiO3 ceramic can generate a large piezoelectric constant of d33 = 276 pC/N at x = 1.5 mol%. According to the dielectric properties results, the high piezoelectricity is possible from the suppressed energy barrier of second-like order transition induced by the incorporation of Li+ and Al3+ ions.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
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2020
·
IF 1.265
Junjie Li,Jinghong Song,Weiwei Li,Bingchu Mei,Zuodong Liu,Yongqiang Zhang
In this study, high concentration (5 mol%) of cerium doped barium fluoride transparent ceramic was fabricated by hot pressing method t a temperature of 1200 °C under 30 MPa. XRD (X-ray Diffraction), SEM (Scanning Electron Microscope), PLE (Photoluminescence Emission) measurements was used to investigate the phase composition, microstructure as well as photoluminescence properties of Ce 3 + : BaF 2 . XEL (X-ray Excited Luminescence) and pulse height spectrum were used to investigate the scintillation properties of this ceramic. The phase composition and microstructure analyses showed that the Ce 3 + : BaF 2 precursor nanoparticles prepared by the co-precipitation method were uniform and have a average size of 25 nm. The highest transmittance of the ceramic was 77% at the wavelength of 2300 nm. The PL (photoluminescence) spectrum showed that the 5d–4f transition of Ce 3 + : BaF 2 transparent ceramic is located at 340 nm. X-ray excited luminescence exhibited only one violet peak at 392 nm. Scintillation decay time measurements showed only a slow component of 437 ns under 662 keV gamma excitation.
研究领域:
材料科学
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光学工程
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DOI
高影响因子
GLASS AND CERAMICS
·
2022
·Vol. 78
·期 11
·506-511
·
IF 0.668
Kai-Tuo Zhang,Yuan Xu,Li-Gui Chen,Lei Fu,Shi-Kui Jia,Zhong-Guo Zhao
BaTiO 3 ceramics are common components of capacitors, sensors, and actuators. Recent research has focused on improving the dielectric properties of BaTiO 3 by using Zr ions for B-site substitution. Additional additives can further enhance ceramic performance. In this work, BaZr 0.15 Ti 0.85 O 3 (BZT) ceramics were prepared by a solid-phase reaction at various contents of added Al ions. All of the ceramic samples had a perovskite cubic phase structure. Compared with BZT ceramics without added Al 2 O 3 , the size of the grains increased considerably, and the grain size decreased slightly in accordance with increasing concentration of Al ions. Addition of Al ions considerably increased the density of the ceramics, yet excessive addition of Al ions decreased the density. The dielectric constants were relatively large when the Al ion content was 0.25 and 1.0 mol.%: 9117 and 8725 C 2 /(N · m 2 ), respectively, at the Curie temperature. Compared with BZT ceramics without Al ions, the dielectric properties were greatly improved, by two different mechanisms (depending on the Al content). In accordance with increasing Al content, the hysteresis loop was narrower, the remanent polarization decreased, and the coercive electric field increased.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Zhujun Jiang,Liying Cheng,Yong Zeng,Zijia Zhang,Yongtao Zhao,Peng Dong,Jimin Chen
A series of porous scaffolds of piezoelectric ceramic barium titanate (BaTiO 3 ) were successfully fabricated by Digital Light Processing (DLP) 3D printing technology in this work. To obtain a high-precision and high-purity sample, the debinding sintering profile was explored and the optimal parameters were determined as 1425 °C for 2h. With the increase of scaffolds porosity from 10% to 90%, the compressive strength and piezoelectric coefficient (d 33 ) decreased gradually. The empirical formulas about the mechanical and piezoelectric properties were obtained by adjusting BaTiO 3 ceramics with different porosity. In addition, the distribution of potential and stress under 100 MPa pressure were studied by the finite element method (FEM).
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Dongxia Tian,Dongyang Liu,Kai He,Fu-Hua Sun,Xiaobing Hu,Shuhan Zheng,Xinyu Wang,Fei Liu,Hong Li
Flexoelectric effect possesses potential applications in electromechanical conversion, and the flexoelectric coefficient of ferroelectrics is greatly larger than that of ordinary dielectrics . Among the ferroelectrics, BaTiO 3 (BT) ceramics are lead-free materials, also receive a high flexoelectric response. However, it is still inferior to the piezoelectric response of lead-based piezoelectric materials . Herein, we inhomogeneously added x wt. % ZrO 2 into BT ceramics ( x wt. % ZrO 2 /BT ceramics, and x = 0.05, 0.5, 1, 2) to enhance the flexoelectric response of BaTiO 3 -based ceramics. The largest effective flexoelectric coefficients ( μ ρ ) of ∼800 μC/m at room temperature (RT) and ∼1500 μC/m near Curie temperature ( T C ∼ 127 °C) were obtained in 0.5 wt % ZrO 2 /BT ceramics, which is ∼6.7 times and ∼3.9 times larger than that of the as-prepared BT ceramics at RT and near T C (∼131.7 °C here) respectively. Although T C of the 0.5 wt % ZrO 2 /BT ceramics decreases compared with that of BT ceramics, its higher μ ρ than that of the as-prepared BT ceramics maintains a wide temperature range, extending to 160 °C. The enhancement of the μ ρ of the 0.5 wt % ZrO 2 /BT ceramics is largely attributed to the compositional heterogeneity between grain boundaries gathered with irregular paraelectric and orthorhombic Ba(Zr, Ti)O 3 , and grains which are tetragonal BaTiO 3 . The compositional heterogeneity is easily shaped into a strain gradient (namely a flexoelectric polarization), which plays a promoting effect on the flexoelectric coefficients.
研究领域:
材料科学
·
物理学
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产品关联
DOI
高影响因子
Science of Advanced Materials
·
2016
·Vol. 8
·期 6
·1200-1207
·
IF 1.812
Zhao Lili,Guo Daidong,Kang Xueliang,Liang Longyue,Yang Zhiyuan,Sang Yuanhua,Liu Hong
Barium titanate (BaTiO3) nanopowders with various morphologies and crystallinities were successfully prepared by three methods. For each of them, the sintering kinetics of the BaTiO3 ceramics tuned by morphology were correlated to exposed crystal facets, crystallinity,
interface curvature and particle size distribution. A highly crystalline particle with flat interface results in a low sintering driving force, and the grain growth proceeds along predetermined growth direction. By contrast, spherical particles with small curvature radius and low crystallinity
possess a high sintering driving force, and growth occurs rapidly in all directions. In this latter case, the resulting ceramic presents a large shrinkage and the highest rate of densification. Small particle size with homogeneous size distribution contributes to the ceramic sintering as well.
The understanding of the morphology tuned sintering kinetic of BaTiO3 ceramics provides a basis for the fabrication of BaTiO3 transparent ferroelectric ceramics in the future.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS LETTERS
·
2024
·Vol. 124
·期 6
·
IF 3.5
Li Hao,Wu Hao,Wang Zhiguo,Xie Zhengqiu,Shu Shengwen,Liu Zhiyong,Ke Shanming,Shu Longlong
Donor doping can increase the dielectric constant of a material by several orders of magnitude due to induced space charge causing interfacial polarization. Giant dielectric properties and interface polarization are also both expected to greatly enhance the flexoelectric behavior of a material. In this work, a typical flexoelectric ceramic material, BaTiO 3 , was selected and donor doped using elemental Nb. Compared with the nominal BaTiO 3 ceramic, the dielectric constant and flexoelectric coefficient of the Nb-doped BaTiO 3 ceramics were significantly improved. The transverse flexoelectric coefficient of 0.3 mol. % Nb-BaTiO 3 was found to increase to nearly 40 times the nominal value, reaching 387 μ C/m. The results indicate that the giant dielectric response, and therefore the giant flexoelectric response, is the result of the combined effects of internal barrier-layer capacitance and surface barrier-layer capacitance. This study not only deepens the understanding of the semiconductor macro-dielectric effect and the flexoelectric mechanism caused by doping, but it also provides a feasible strategy for the design of giant dielectric/flexoelectric response materials and related devices with high dielectric constants and flexoelectric coefficients.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Zhuohao Qiu,Gaoyuan Chen,Xixi Bao,Jitao Xu,Chengyi Chu,Guangjian Peng,Jianjun Guo,Yuchuan Cheng,Aihua Sun
Barium titanate ceramics exhibit great potential in ceramic capacitors due to their excellent dielectric properties. However, with the highly integrated advancement in electronic components, the preparation of high-capacitance ceramic capacitors with complex structural design has been the focus in current research. In this study, the complex structural barium zirconium titanate is first prepared through direct ink writing (DIW) technique. Subsequently, based on the regulation of zirconium substitution on the phase transition temperature of barium titanate, we reasonably designed zirconium-substituted barium titanate ceramics with varying stoichiometric ratios to regulate the three-phase transition temperatures of zirconium titanate ceramics, and following optimized the sintering temperature of the over-substituted barium zirconium titanate, thus improving the dielectric properties of the barium titanate. The results demonstrate that the solid content of 65 % exhibited the optimal forming precision and the highest densification. Additionally, the over-substituted zirconia alter the phase structure of barium titanate, increasing the proportion of tetragonal phase and subsequently elevating the dielectric constant of the specimens. Notably, among all sintering temperatures tested, the specimen sintered at 1400 °C display the highest proportion of tetragonal zirconia-barium titanate and an optimal dielectric constant. This research offers valuable technical and theoretical insights for the preparation and utilization of zirconium-substituted barium titanate ceramics with intricate structures.
研究领域:
材料科学
·
电子工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）