JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Yutian Lu,Weijia Guo,Chongyang Zhang,Zhenxing Yue
The rapid development of fifth/sixth-generation (5 G/6 G) telecommunication technologies has led to increased demands for silicate ceramic materials. In this work, Ge 4+ -substituted diopside , CaMg 0.9 Zn 0.1 Si 2- x Ge x O 6 (CMZSG, x = 0.0–2.0) ceramics were synthesized via the conventional solid-state method. All samples were sintered densely at 1200 ℃ for 4 h. CMZSG ceramics keep a single phase with C 2/ c and the lattice parameters vary smoothly with x . When 0.1 ≤ x ≤ 0.8, Ge 4+ substitution prevents the abnormal grain growth . CMZSG ceramics have enhanced dielectric properties after substituting Ge 4+ , and the sample with x = 0.1 has the greatest dielectric properties with ε r = 7.78 and Q × f = 190,300 GHz. The dielectric properties in the microwave and terahertz bands are compared, and the larger ε r and Q × f values in the terahertz band are found due to the withdrawal of the partial polarization mechanism and different measurement methods. The relationship between lattice distortions and the dielectric properties is established. Both the local distortion in [Si/GeO 4 ] tetrahedra chain and the distortion within [Si/GeO 4 ] tetrahedron are found to contribute to the enhancement of Q × f values. Furthermore, the increased lattice expansion and the distortion within [Si/GeO 4 ] tetrahedron contribute to a larger negative τ f . These conclusions can guide us to design silicate ceramics with higher Q × f values and near-zero τ f for application. The CaMg 0.9 Zn 0.1 Si 1.9 Ge 0.1 O 6 ceramics exhibit excellent dielectric properties with ε r = 7.48 and Q × f = 303,400 GHz in the terahertz band, rendering it a promising dielectric material for future terahertz mobile communication systems.
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
·
介电材料
·
通信技术
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2023
·Vol. 106
·期 8
·4794-4805
·
IF 3.9
Kui Liu,Yuran Yang,Dainan Zhang,Liang Shi,Xueying Wang,Qisheng Yin,Cheng Liu,Jie Li,Yulong Liao,Huaiwu Zhang
Herein, Li 1+ x Mg 0.5 Ti 0.5 O 2 (0.000 ≤ x ≤ 0.075) ceramics with excess lithium were prepared by solid-state reaction method to compensate for lithium volatilization, thus optimizing dielectric properties. The second phase Mg 2 TiO 4 decreases with excess lithium content and eventually disappears at x = 0.05. Of these, Li 1.0375 Mg 0.5 Ti 0.5 O 2 illustrates the best dielectric properties with ε r = 16.58, Q × f = 120712 GHz (@9.18 GHz), and τ f = −16.31 ppm/°C. From the point of view of non-intrinsic factors, excess lithium at optimum ratios slightly facilitates the sintering of the ceramics, improves densification, and increases the grain size, resulting in improved dielectric properties. For intrinsic factors, a slight increase in bond ionicity results in a slight improvement in ε r . First-principles calculations demonstrate that suitable excess lithium increases electron cloud density in the internal space of Li/Mg/TiO 6 octahedron and increases band gap, thus optimizing the dielectric properties. The same results were obtained from the perspective of lattice vibrations. The modified Li 1.0375 Mg 0.5 Ti 0.5 O 2 ceramics offer great potential for future microwave communication technology.
研究领域:
材料科学
·
电气工程
·
陶瓷
·
微波技术
✓ 已验证
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 23
·5824
·
IF 3.1
Guoyu Zhang,Lu Li,Yanxin Nan,Peng Li,Tao Deng,Zhipeng Lei,Yuanyuan Li,Jianhua Zhang
In this work, the effects of different sintering temperatures and TiO2concentrations on the dielectric properties of ZrO2and Nb2O5pre-doped CaCu3Ti4O12(CCTO) ceramics were investigated. These doped ceramics were sintered at temperatures of 1020, 1030, and 1040 °C, exhibiting the lowest dielectric loss of 0.01, which consistently remained below 0.03 across a wide frequency range from 10 to 105Hz. Simultaneously, they maintained a high dielectric constant of more than 3000 and remarkably met the requirements for an X8P capacitor (Δε′ ≤ ±10% at temperature range from −55 to 150 °C). It was clarified that TiO2doping increased grain boundary resistance, leading to the reduced dielectric loss, and elevated the grain boundary activation energy, thereby enhancing the temperature stability. The TiO2-doped CCTO-based ceramics also demonstrated reduced sensitivity to variations in sintering temperature, highlighting their excellent manufacturability. This characteristic holds great promise for the fabrication of CCTO-based ceramics, which usually exhibit poor repetitiveness.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 11
·10651-10659
·
IF 2.195
Huang Xuechen,Liu Bang,Wang Shuanghu,Liu Yuxi,Wu Gang
Bi 2 O 3 - and MgO-doped BaTiO 3 –(Na 1/4 Bi 3/4 )(Mg 1/4 Ti 3/4 )O 3 (BT–NBMT) ceramics were synthesized from a solid-state approach, and then the impacts of Bi 2 O 3 and MgO dosages on the structures and dielectric characteristics were studied. Obvious dual peaks were observed with Bi 2 O 3 dosage to 0.04 and MgO dosage to 0.02. The low-temperature dielectric stability and grain size of the Bi 2 O 3 dopant were improved, while those of the MgO dopant hardly changed with MgO dosage to 0.02, indicating the core/shell microstructure of BT–NBMT was formed following the dissolving-precipitating mechanism of BT systems doped with low-melting-point substances. The low-temperature dielectric stability of the Bi 2 O 3 - or MgO-doped BT–NBMT ceramics first improved and then deteriorated with the increase of doping concentrations. High-temperature stability and diffuse-state transition were found in the optimal ceramics. The second phases of Bi 2 O 3 and MgO, magnesium titanium compounds were observed in Bi 2 O 3 and MgO dopants, respectively. Bi 2 O 3 -doped and MgO-doped ceramics exhibited a fine-grained microstructure and significant grain growth, respectively, and the core/shell microstructure was responsible for the dielectric temperature stability for Bi 2 O 3 dopants and collapsed to a homogeneous one with remarkable grain growth and the second phases for MgO dopants.
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 SCIENCE
·
2025
·
IF 3.9
Chen Huyue,Li Yitao,Wang Jingrong,Lu Tengfei,Xu Haiping,Yang Dandan,Chen Lifei
As the demand for lightweight and compact integrated devices accelerates, dielectric materials are pivotal in enabling efficient energy storage. Composite materials, particularly those combining a polymer matrix with two-dimensional (2D) conductive MXene fillers, have emerged as promising candidates for improving dielectric performance. However, their high dielectric constant is often accompanied by significant dielectric loss, limiting their application in high-frequency circuits and electronic devices. This study investigates a ternary composite system consisting of polyvinylidene fluoride (PVDF) as the matrix, Ti 3 C 2 T x MXene as a conductive filler, and strontium titanate (SrTiO 3 ) as a ceramic filler to enhance dielectric properties. The ternary composites were prepared through a combination of physical mixing followed by a hot-pressing process. The results demonstrate that the MXene/SrTiO 3 /PVDF composites achieve a notable reduction in dielectric loss while retaining a high dielectric constant. At 12 wt% MXene, the composite achieves a dielectric constant of 117.8 at 10 3 Hz, 14.7 times higher than pure PVDF, with dielectric loss reduced by 71.4% compared to MXene/PVDF composites. Furthermore, the incorporation of SrTiO 3 markedly enhances the thermal stability, elevating the thermal decomposition temperature of the composite to 437.88 °C, up from 357.9 °C for pure PVDF. This research presents a promising strategy for developing capacitors with superior dielectric properties and enhanced thermal stability, suitable for high-temperature applications.
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
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Changhai Zhang,Tongqin Zhang,Mengjia Feng,Yang Cui,Tiandong Zhang,Yongquan Zhang,Yu Feng,Yue Zhang,Qingguo Chi,Xianli Liu
The increasing energy problem and the demand of environmental protection raise higher requirements for the development of clean energy. Dielectric capacitors have attracted lots of attention as a supporting facility of energy storage and conversion for clean energy, but their further development is limited by the low energy storage performance. In this paper, all-organic composite dielectrics were reported, with a poly(methyl methacrylate) (PMMA)/poly(vinylidene fluoride) (PVDF) composite dielectric with different mixing ratios as the matrix and the organic molecular semiconductor with high electron affinity [6,6]-phenyl C61 butyrate acid methyl ester (abbreviated as PCBM) as fillers. The related test results show that with the increase in the doping contents of PCBM, the energy storage density increases obviously. When the doping content of PCBM is 0.9 wt %, the PMMA/PVDF-based organic composite dielectric possesses an optimal breakdown field of 685.67 kV mm–1, accompanying excellent energy storage performances (Ue, ∼21.89 J cm–3; η, ∼70.34%). The PVDF blended with PMMA strategy not only restrains the ferroelectric polarization loss of PVDF but also improves the breakdown strength of the polymer. More importantly, the polarization and breakdown strength of the composites can be synergistically enhanced by filling with PCBM fillers.
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
EPL
·
2016
·Vol. 114
·期 5
·56003
·
IF 1.963
Lidong Dai,Lei Wu,Heping Li,Haiying Hu,Yukai Zhuang,Kaixiang Liu
In this study, the effect of pressure on undoped and 5% yttrium-doped SrZrO3 (SZY0 and SZY5) were conducted from the ambient condition to {\sim}25\ \text{GPa} with a diamond anvil cell. The comparison of the high-pressure Raman spectra of SZY0 and SZY5 indicate that SZY0 displays a rigid structure without any structural modification, whereas for SZY5 a structural transition at {\sim}15\ \text{GPa} is revealed. Some characteristic physical parameters such as bulk conductivities, grain boundary conductivities, Warburg diffusion coefficient, transference number and bulk relaxation frequency were determined by the high-pressure impedance spectroscopy data. An obvious discontinuous inflexion point (at {\sim}13\ \text{GPa}) for SZY5 sample is observable which was also verified the phase-transition of the Raman spectroscopy results. A mixed conduction mechanism for both SZY0 and SZY5 are coexisting for both SZY0 and SZY5 in a wide pressure range. The pressure-induced phase-transition of SZY5 would result in an inversion of conduction mechanism that is characterized by the dominant charge carriers transformation from electron to ion. The Maxwell-Wagner relaxation arising at the interfaces of grain and grain boundary indicates that Y-doping and pressure could make the ions diffusion much easier through the boundaries and finally enhance the dielectric performance of the sample. It is suggested that pressure could be a useful tool to manipulate the microstructure and dielectric performance of polycrystal through altering the grain boundary distribution.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Chun Tong,Xinlei Shen,Chang Feng,Xia Feng,Haikui Zhu,Lixi Wang
Temperature-stable ULTCC composite (1- x )Li 3 AlMo 3 O 12 - x Li 0.5 Bi 0.5 MoO 4 ceramics were prepared by solid-state reaction method. X-ray and EDS results showed that Li 3 AlMo 3 O 12 phase and Li 0.5 Bi 0.5 MoO 4 phase exist independently, and no other phase is generated. Due to the low sintering temperature of both two phases, the composite ceramics can obtain high density at 560 ℃. Microwave dielectric properties mainly depend on the ceramic Li 0.5 Bi 0.5 MoO 4 content x , the addition of Li 0.5 Bi 0.5 MoO 4 effectively increases the τ f of Li 3 AlMo 3 O 12 from −65.05 ppm/℃ to 4.96 ppm/℃, but caused the dielectric loss increase. When x =0.45 and sintered at 560 ℃, microwave dielectric properties of 0.55Li 3 AlMo 3 O 12 -0.45Li 0.5 Bi 0.5 MoO 4 ceramics with close zero τ f : ε r = 15.32, Q × f = 13,158 GHz, τ f = 4.96 ppm/℃.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Wenchao Lin,Pengrong Ren,Yuhui Wan,Shu Yang
BaTiO 3 , Ba(Ti 0.2 Zr 0.2 Sn 0.2 Hf 0.2 Nb 0.2 )O 3 , SrTiO 3 , Sr(Ti 0.2 Zr 0.2 Sn 0.2 Hf 0.2 Nb 0.2 )O 3 , (Sr 0.5 Ba 0.5 )TiO 3 and (Sr 0.5 Ba 0.5 )(Ti 0.2 Zr 0.2 Sn 0.2 Hf 0.2 Nb 0.2 )O 3 ceramic samples were prepared using a traditional solid-state reaction method. XRD analysis shows that all the samples are a single-phase perovskite structure. After the addition of B-site high-entropy components Sn 4+ , Zr 4+ , Hf 4+ , and Nb 5+ in BaTiO 3 , the permittivity and dielectric loss decrease significantly, and the temperature stability of the permittivity is remarkably improved. Compared with the undoped sample, the insulation resistance of the high-entropy ceramic sample increases exponentially. The incorporation of high entropy components changes the conduction mechanism, improves the insulation performance, and significantly decreases thermal conductivity, which improves the adiabatic performance of ceramics. These results demonstrate that the high entropy strategy can significantly influence the electrical and thermal properties of BaTiO 3 and SrTiO 3 -based ceramics. Our work provides a new idea for the modification of functional ceramic materials and offers new promising candidates of dielectrics applied for Class-I type ceramic capacitors.
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
Crystals
·
2020
·Vol. 10
·期 3
·173
·
IF 2.404
Panpan Zhang,Ke Zhang,Shuliang Dou,Jiupeng Zhao,Xiangqiao Yan,Yao Li
Several kinds of polyimide (PI) films stemmed out of 4, 4’–diaminodiphenyl ether, as well as various structurally various aromatic dianhydride, were prepared. The films’ mechanical, dielectric, and dynamic mechanical attributes were put under investigation. According the findings, the PI films’ performance is significantly different as a result of their diverse structure. PI’s dielectric constant and dielectric loss tangent of abides by the increasing order below: PMDA-PI>BTDA-PI>BPDA-PI. Moreover, the electric breakdown strength of BTDA-PI (478.90 kV/mm) presents a lot higher value compared to the one PMDA-PI (326.80 kV/mm) and BPDA-PI (357.07 kV/mm). In particular, BTDA-PI film possesses high electric breakdown strength about 478.90 kV/mm. In addition, PI’s glass transition temperature (Tg) are, respectively, 276 °C (BTDA-PI), and 290 °C (BPDA-PI), as well as 302 °C (PMDA-PI). Therefore, in virtue of their various structures and performances, practical applications of PI films can exert significant role in the electronics and microelectronics industries.Keywords:polyimide;film;dielectric properties;thermal properties
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 ELECTRONIC MATERIALS
·
2023
·Vol. 52
·期 11
·7164-7170
·
IF 2.1
Li Yingxiang,Liang Deyin,Zhang Xing,Xiong Zhe,Tang Bin,Si Feng,Fang Zixuan,Li Hao,Shi Zitao,Chen Jingjing
This study presents the dielectric properties of Ba 2 Zr 2 Si 3 O 12 ceramics, synthesized using the solid state method. The cubic crystal structure of Ba 2 Zr 2 Si 3 O 12 ceramics was conclusively verified through the analysis of XRD patterns and subsequent structural refinement. Refined lattice parameters of a = b = c = 10.23178 Å were found, with a corresponding unit cell volume of V = 1071.159026 Å 3 . The grain microstructure of the ceramics was characterized using SEM, which showed density of 97.6% for the Ba 2 Zr 2 Si 3 O 12 ceramic. The Si-O bond valences ( V Si-O ) were found to be closely related to the τ f of the Ba 2 Zr 2 Si 3 O 12 ceramics. The microwave dielectric properties of the Ba 2 Zr 2 Si 3 O 12 ceramics sintered at 1490°C were ascertained to be ε r = 15.08, Q × f = 14885 GHz ( f = 9.9 GHz), and τ f = −78.6 ppm/°C.
研究领域:
材料科学
·
无机非金属材料
·
微波介质陶瓷
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2022
·Vol. 25
·期 1
·95-107
·
IF 3.756
Lei Wang,Xudong Liu,Jinsheng Li,Mu Zhang,Xiaoguo Bi,Zhixin Ma,Jialin Chen,Xudong Sun
High-performance dielectric materials are essential components of electronic devices. In this work, RE-doped SrTiO3 (RE = La, Nd, Yb) single crystals with excellent dielectric properties were prepared by the Verneuil method. For La-STO and Nd-STO, the RE ions are substituted for Sr2+ only, and the excellent dielectric properties are mainly caused by defect dipoles associated with oxygen vacancies including and defect dipole clusters. For Yb-STO, Yb3+ partially replaces Ti4+, forming an additional defect dipole , resulting in the best dielectric properties (ε′ = 3.6 × 104, tan δ = 0.0036 under 1 kHz). In addition, N2 atmosphere treatment promotes the production of oxygen vacancies and Ti3+ and the formation of more defect dipoles, thus further optimizing the dielectric properties of Yb-STO (ε′ = 4.9 × 104, tan δ = 0.004 under 1 kHz). This work suggests that the dielectric properties of RE-doped SrTiO3 materials are closely related to oxygen vacancies, and the simultaneous substitution of Sr2+ and Ti4+ should enable obtaining dielectric properties superior to those of the substitution of Sr2+ only. The present work provides a clearer understanding of the origin of SrTiO3 dielectric properties, which is of great significance to the development of SrTiO3-based dielectric materials.
研究领域:
材料科学
·
凝聚态物理
·
电子器件
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）