International Journal of Applied Ceramic Technology
·
2022
·Vol. 19
·期 6
·3392-3402
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IF 2.328
Tong Shi,Fan Zhang,Wuyou Sun,Jinrui Li,Yu Bai,Chao Wang,Shiying Liu,Xin Wang,Yunhong Yang,Zhan jie Wang
In this study, 0.94Mg (1-3 x /2) Ce x TiO 3 −0.06(Ca 0.8 Sr 0.2 )TiO 3 (MCe x T−CST, 0≤ x ≤0.01) composite ceramics were prepared at a low temperature of 1175°C by using the 50-nm-sized powders. The effects of Ce 3+ doping on crystalline phase, microstructure, and microwave dielectric properties of MCe x T−CST were studied. A main ilmenite (Mg,Ce)TiO 3 phase and a minor perovskite (Ca 0.8 Sr 0.2 )TiO 3 phase coexist well with the appearance of impurity MgTi 2 O 5 phase in MCe x T−CST. The dielectric properties of MCe x T−CST are affected by the molecular polarizability, the impurity phase, and the Ce 3+ doping. The replacement of Mg 2+ by high valence Ce 3+ could effectively inhibit the formation of oxygen vacancy, resulting in the enhancement of Q×f . When x = 0.005, MCe x T−CST exhibits microwave dielectric properties with a moderate ε r of 21.5, a high Q×f of 67 000 GHz, and a near-zero τ f of −0.74 ppm/°C. The results reveal that the Ce 3+ substitution is a prospective approach to optimize the microwave dielectric properties of MgTiO 3 -based ceramics.
研究领域:
材料科学
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电子材料
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高影响因子
Ceramics-Switzerland
·
2024
·Vol. 7
·期 1
·426-435
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IF 2.7
Yuan-Bin Chen,Yu Fan,Shiuan-Ho Chang,Shaobing Shen
In this study, we used solid-state synthesis to prepare Ba[(ZnxCo1−x)1/3(Nb0.5Ta0.5)2/3]O3microwave ceramics for mobile communications. Compared with Ba[Zn1/3(Nb0.5Ta0.5)2/3]O3, in the prepared materials, Co2+substitution with Zn2+improved the Q × f value and enabled densification and sintering at a lower temperature. We used X-ray diffraction (XRD) and scanning electron microscopy (SEM) to analyze the obtained microstructure. Ba[(ZnxCo1−x)1/3(Nb0.5Ta0.5)2/3]O3was found to have a 1:2 ordered hexagonal structure, and its Q × f value increased with the increase in sintering temperature. In this work, excellent microwave dielectric properties—τf= −0.7 ppm/°C, εr= 34.5, and Q × f = 110,000 GHz—were obtained by sintering Ba[(Zn0.3Co0.7)1/3(Nb0.5Ta0.5)2/3]O3at 1400 °C for 5 h.
研究领域:
材料科学
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电子工程
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高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Chang Jiang,Linzhao Ma,Guo Tian,Longxiang Jiang,Hongzhi Xiao,Qianbiao Du,Hao Li
Novel spinel-type Li 2 Mg 2 Ga 2 Ti 3 O 12 ceramics were prepared by the solid-state method. Rietveld refinement revealed that the Li 2 Mg 2 Ga 2 Ti 3 O 12 ceramics possess a cubic spinel structure with the F d 3 ‾ m ( 227 ) space group. Raman spectrum analysis indicated that the Q × f and FWHM of ceramics exhibit an inverse relationship. According to the P-V-L theory, the Ti-O bond has the highest percentage of contribution to both of bond ionicity and lattice energy, indicating a significant impact on ε r and Q × f , respectively. The Li 2 Mg 2 Ga 2 Ti 3 O 12 ceramics showed the best microwave dielectric properties ( ε r = 15.72, Q × f = 69,633 GHz, and τ f = −20 ppm/°C), sintering at an optimum temperature of 1200 °C. Additionally, a dielectric resonance antenna, on the basis of Li 2 Mg 2 Ga 2 Ti 3 O 12 ceramics was designed and simulated.
研究领域:
材料科学
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物理学
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
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IF 4.65
Moke Zhou,Bin Tang,Zhe Xiong,Xing Zhang,Shuren Zhang
In this study, the crystal structures and microwave dielectric properties of the Y 3 Al 5 O 12 garnet (YAG) doped with Magnesium (Mg) were investigated. The samples were prepared by a method that the isostatic pressing technique was introduced into the conventional preparation of microwave dielectric ceramics . From XRD patterns of resulted compound, we see Y 3 Al 5−x Mg x O 12–1/2x ( x = 0–0.045) samples form a solid solution with MgO. The lattice parameters of the Y 3 Al 5−x Mg x O 12–1/2x samples have been refined by the Rietveld method, and the unit cell volume of samples swell up slightly as the x value increases. The SEM images demonstrate that the porosity in the system has been effectively eliminated and the values of the relative density significantly increase due to the addition of Mg 2+ , which is conducive to the improvement of Q × f value. The TEM results present the high crystallinity of Y 3 Al 5−x Mg x O 12–1/2x samples. The Raman spectra study illustrates the relationship between the vibrational FWMH values corresponding to the internal loss and the Q × f value. Finally, the Q × f value has been dramatically promoted from 133,209 GHz at x = 0–218,168 GHz at x = 0.035.
研究领域:
材料科学
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陶瓷学
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2025
·
IF 6.2
Yuan-Bin Chen,Ling Tang,Xiuyuan Su
Low-temperature sintered microwave dielectric ceramics are gaining increasing attention for next-generation wireless communication systems, particularly within the 6 G frequency range. However, materials that simultaneously exhibit ultra-low dielectric loss and low sintering temperatures remain scarce. In this study, Nd 2 [Zr 1-X (Bi 0.5 Ta 0.5 ) X ] 3 (MoO 4 ) 9 ceramics were prepared via a conventional solid-state reaction method and exhibited a single-phase structure with a trigonal symmetry (space group R 3 ¯ C, No. 167). The optimal sample at x = 0.11 sintered at 750 ℃ showed excellent performance: ε r = 11.4, Q×f = 186,300 ± 8900 GHz, and τ f = –42.9 ppm/℃. The elevated Q×f value is chiefly ascribed to increased lattice energy, with its variation more plausibly arising from intrinsic effects within the material. The dielectric constant (εᵣ), analyzed using the Clausius–Mosotti equation, was predominantly influenced by ionic polarizability. According to P–V–L theory, the effective bond strength f iNd–O played a major role in determining εᵣ, while τ f was governed by the bond energy and thermal expansion behavior of Mo–O bonds. Raman spectroscopy further confirmed the structure–property relationships. These results suggest that B-site substitution with (Bi 0.5 Ta 0.5 ) 4+ not only promotes densification and increases lattice energy, but also maintains thermal stability, thereby enhancing Q×f without compromising τ f . This system offers strong potential for integration into future microwave dielectric components.
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JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 7
·1-13
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IF 2.8
Hu Qi,Teng Yuancheng,Zhao Xiaofeng,Zhou Fei,Arslanov Temirlan,Dai Bo
Zn 1− x Ni x ZrTa 2 O 8 ( x = 0.02, 0.04, 0.06, 0.08, 0.10, 0.12) microwave dielectric ceramics were synthesized by traditional solid-state method. The effect of introducing Ni–O bonds to replace part of Zn–O bonds on the ceramic lattice and microwave dielectric properties was systematically studied. An appropriate amount of Ni 2+ substitution improves the microscopic morphology of crystal, including the grain size, number of pores, number of grain boundaries, and the grain uniformity, giving rise to an increase in the compactness of ceramics and, thereby enhancing the microwave dielectric properties. The Raman analysis prove that the introduction of Ni 2+ is beneficial to enhance the vibrational peak intensity of the oxygen octahedron and effectively improve the Q × f value. However, the introduction of excessive Ni 2+ will lead to the decrease of lattice oxygen and the increase of adsorbed oxygen, and the crystal will become relatively active and unstable, and the microwave performance will decrease. In addition, the substitution of Ni 2+ can also effectively control the resonance temperature coefficient, which is beneficial to improve the τ f value. As a result, Zn 0.94 Ni 0.06 ZrTa 2 O 8 exhibits excellent microwave dielectric properties: ε r = 32.15, Q × f = 15,7500 GHz, τ f = − 33.1 ppm/°C, presenting as a potential candidate for low-loss microwave dielectric materials.
研究领域:
材料科学
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电子材料
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2026
·Vol. 47
·期 3
·118901
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IF 6.3
Zipeng Huang,Lili Gan,Lihua Qiao,Yanru Wu,Chenru Hao,Li Cheng,Ziqiang Chi
Microwave dielectric ceramics for next-generation communication systems require a high relative permittivity (
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高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Zhijian Wang,Lanlan Liu,Qifeng Du,RuiTao Tang,Jun Ai,Ying Chen
Ti-related oxide ceramics often exhibit excellent microwave dielectric properties and are widely applied in the microwave communication field. However, their microwave dielectric properties are often influenced by unstable defects, which are caused by the relatively low oxygen partial pressure at high sintering temperatures . In this work, Al 2 O 3 was introduced to improve the defect structures of the 0.85CeO 2 -0.15TiO 2 ceramics. According to the XPS pattern and AC conductivity analysis, Al 2 O 3 doping could stabilize the valence state of Ti but increase the oxygen vacancy concentration. Q × f first increased and then decreased as the Al 2 O 3 content increased. The highest Q × f value of 54361 GHz was obtained for the CTA0.015 sample sintered at 1275 °C, as well as the ε r of 29.41 and τ f of +7.8 ppm/°C. Finally, the CTA0.015 sample was used to prepare a microstrip antenna via the screen-printing process, which exhibited a good temperature-independent resonant frequency and indicated good application prospects.
研究领域:
材料科学
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电子工程
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Weijia Guo,Yutian Lu,Chongyang Zhang,Zhenxing Yue
Low-loss (high- Q × f , where Q = 1/tan δ ) dielectric ceramics can help achieve efficient microwave signal transmission and reduce heat generation. In the traditional Ca-Ln-Ti-O perovskite system (where Ln = rare earth) with the general formula of Ca 1– x Ln 2 x /3 TiO 3 (CST x ), the sharp decline in the Q × f value when x > 0.5 remains unexplained, posing a challenge for designing low-loss ceramics. In this study, CST x ceramics ( x ≤ 0.7) are synthesized via the solid-state reaction method, with a focus on their structure, defects, and broadband dielectric properties. A significant discrepancy between the Q × f values in the microwave and terahertz bands is found when x ≥ 0.6, suggesting the presence of additional loss mechanisms in the microwave band beyond ion displacement depolarization. Meanwhile, the low-frequency dielectric spectra show a weak dielectric relaxation in the low-temperature region, attributed to the partially ordered A -site vacancies. Therefore, this relaxation can act on the microwave frequency band at room temperature, resulting in a sharp decline in Q × f values. Such low-frequency and low-temperature dielectric relaxation should not be ignored in the research of microwave dielectric ceramics. These findings provide a crucial theoretical reference for developing low-loss microwave dielectric ceramics.
研究领域:
材料科学
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电子工程
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高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2023
·Vol. 107
·期 1
·367-376
·
IF 3.9
Weijia Luo,Xubin Wang,Baiheng Bai,Jianli Qiao,Xingcong Chen,Yongzheng Wen,Jingbo Sun,Lingxia Li,Ji Zhou
Internal strain is considered to be related to the dielectric loss of tungsten bronze structural ceramics, while its effects often cannot be effectively distinguished from non-intrinsic factors. To quantitatively determine the influential mechanism of dielectric loss by internal strain, B-site controllable co-substituted (Al 3+ , Ga 3+ , and Sc 3+ ) Ba 4 Nd 9.33 Ti 18 O 54 ceramics with single phase were designed and synthesized, and the ratio is designed with the equivalent radius of substituted ions is equal to Ti 4+ . Through calibrating the global instability index, the relatively straightforward relationship between internal strain and Q×f value is established. As a result, a loss gradient ( Q×f value from 8468 to 14311 GHz) and an almost stable real part of permittivity (ε r ∼ 68 with near-zero τ f ) can be obtained. Not only does it provide direct evidence for the effectiveness of internal strain control on dielectric loss, but also decouples three key parameters of microwave dielectric ceramics, which may be of great significance in future device physics, especially for all-ceramic non-Hermitian devices.
研究领域:
材料科学
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陶瓷工程
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电气工程
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高影响因子
CERAMICS INTERNATIONAL
·
2025
·Vol. 51
·期 30
·63013-63021
·
IF 5.6
Ning Zhang,Junqi Chen,Ning Guan,Huaicheng Xiang,Ying Tang,Yuandong Qin,Liang Fang
Two novel ceramics, Li 2 Mg 2 Ga 2 Ti 3 O 12 (LMGT) and Li 2 Zn 2 Ga 2 Ti 3 O 12 (LZGT), featuring a spinel structure, were synthesized utilizing the solid-state method. Comprehensive characterization confirms that LZGT ( P 4 3 32) forms a B-site 1:3 ordered spinel, while LMGT ( Fd -3 m ) adopts a disordered spinel structure. The ceramics exhibit outstanding microwave dielectric properties, characterized by low ε r of 14.92 and 19.11, high Q×f of 120,000 and 93,800 GHz, and negative τ f of −40.21 and −32.83 ppm/°C for LMGT and LZGT, respectively. The observed ε r values significantly exceed theoretical values due to underestimated Ti 4+ polarizability along with the rattling effect of Ti 4+ and Ga 3+ . Q×f values correlate with packing fraction, lattice energy, and electrical properties. The negative τ f values stem from dominant positive τ ε and τ αm contributions. Utilizing LMGT with ultra-low loss, a dielectric resonator antenna was designed, achieving a radiation efficiency of 93.01 % and a gain of 6.12 dBi at 6.60 GHz, highlighting significant potential for C-band communication satellite applications.
研究领域:
材料科学
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无机非金属材料
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电子功能材料
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微波技术
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天线工程
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固态化学
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高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 27
·1-9
·
IF 2.8
He Chuansheng,Li Yingxiang,Wang Fei,Hou Zegui,Liu Wei,Liang Deyin,Tang Bin,Fang Zixuan,Shi Zitao,Chen Jingjing,Li Hao
For the timely transmission of signals, the research of low dielectric constant microwave ceramics is essential. In this study, a new type of low-permittivity Lu 2 MgAl 4 SiO 12 microwave dielectric ceramic was prepared by traditional solid-phase method. The successful synthesis of Lu 2 MgAl 4 SiO 12 ceramics with cubic crystal system and space group Ia-3d (230) was determined by XRD and Rietveld refinement. SEM observation confirmed the garnet structure of Lu 2 MgAl 4 SiO 12 ceramics, and verified the dense structure of the ceramic samples with a relative density of 99.1%. In addition, the influence of relative density and packing fraction on Q × f was studied by analyzing the Lu 2 MgAl 4 SiO 12 system. The findings revealed that τ f was affected by the valence state of V Si-O bond. Finally, Lu 2 MgAl 4 SiO 12 sample sintered at 1490 °C demonstrated notable microwave properties ( ε r = 9.13, Q × f = 15,100 GHz, τ f = –47.1 ppm/°C).
研究领域:
材料科学
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无机非金属材料
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介电材料
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微波技术
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陶瓷工程
·
晶体结构
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高影响因子
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