JOURNAL OF ALLOYS AND COMPOUNDS
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2023
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IF 6.2
Xiaohui Wu,Yulan Jing,Yuanxun Li,Hua Su
The comprehensive properties and sintering temperature of microwave dielectric ceramics are the key factors limiting their practical application. In this work, a novel strategy of complex (Co 1/3 Nb 2/3 ) 4+ ions substituted and adding glass (Li 2 O-B 2 O 3 - SiO 2 -CaO-Al 2 O 3 : LBSCA) was proposed to greatly enhance the microwave dielectric properties of Ba 3 Ti 4- x (Co 1/3 Nb 2/3 ) x Nb 4 O 21 (0 ≤ x ≤ 12 mol%, x CN-BTN) ceramics. A new ceramic of (Co 1/3 Nb 2/3 ) 4+ substitution improved hexagonal phase BTN was successfully fabricated and systematically investigated. As the increased of (Co 1/3 Nb 2/3 ) 4+ ions concentration, the Q× f was greatly increased because of higher packing fraction, and the reduction in the [Nb1/Ti1O 6 ] octahedral distortion caused great changes of τ f . Besides, the P-V-L theory revealed that the Ti/Nb ratio greatly contributed in permittivity ε r , and the Nb-O bonds mainly affected dielectric loss, especially in Nb(1)-O2(1) bond. As a result, the superior microwave dielectric properties were obtained in 6CN-BTN ceramic sintered at 950 °C: ε r ∼40.99 ± 0.48, Q× f ∼17,310 ± 565 GHz, and τ f ∼8.62 ± 4.34 ppm/°C. More encouragingly, 6CN-BTN showed good compatibility with silver, making it a promising K 40 LTCC material for filter and dielectric resonators . This study presented a new strategy to improve the properties of BTN-based materials by complex ions substitution, which was expected to provide a general approach for the design of advanced microwave dielectric ceramics for other material systems.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Xiaohui Wu,Qin Zhang,Fangyi Huang,Xingyu Huo,Fuyu Li,Yulan Jing,Yuanxun Li,Hua Su
In this work, a new low loss Ba 3 Ti 4- x (Mn 1/3 Nb 2/3 ) x Nb 4 O 21 (MN-BTN, 0 ≤ x ≤ 12 mol%) ceramics configuration was presented through preparing by the solid-state route. The XRD patterns, Rietveld refinement , microstructure, and microwave properties were systematically analyzed. All the fabricated MN-BTN ceramics belonged to the hexagonal structure with a P 6 3 / mcm space group. More specifically, the 6MN-BTN ceramic exhibited a high relative density of ~92.3 %, homogeneous grains distribution with an average size of ~71.95 µm, and several excellent microwave dielectric properties : ε r = 59.67, Q× f = 16,226 GHz, τ f = +103.9 ppm/℃ sintered at 1220 ℃. The incorporation of 1.5 wt % BaCu(B 2 O 5 ) (BCB) compound within the 6MN-BTN ceramic not only effectively reduced the sintering temperature from 1220 ℃ to 950 ℃, but also the excellent microwave dielectric properties were maintained: ε r = 42.33, Q× f = 11,300 GHz, τ f = +24.7 ppm/℃. Interestingly, the 6MN-BTN + 1.5 wt % BCB ceramic showed better chemical compatibility with Ag. The proposed 6MN-BTN + 1.5 wt % BCB ceramic configuration could be regarded as a promising material for LTCC applications.
研究领域:
材料科学
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陶瓷工程
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微波工程
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2024
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IF 3.5
Xiaohui Wu,Xixi Wang,Yulan Jing,Yuanxun Li,Hua Su
With the emergence of 5G–6G communication technology, the miniaturization and integration of electronic components are crucial. Ba 3 Ti 4 Nb 4 O 21 (BTN) ceramics with hexagonal structures have attracted special attention due to their high dielectric constant, which shows greater application potential in communication base stations and dielectric resonators. However, its high sintering temperature and low-quality factors also greatly limit the application field. In this paper, boric acid (H 3 BO 3 ) as a dopant, was used to investigate the influence on the structure, microstructure, Raman spectrum, and microwave properties for Ba 2.92 Cu 0.08 (Zn 1/3 Nb 2/3 ) 2 Ti 2 Nb 4 O 21 (BCZTN)- x HB (0.25≤ x ≤1.25 wt%) ceramics. The results reflected that H 3 BO 3 was an effective additive, which could promote ceramic densification, accelerate grain growth and uniform distribution, and enhance its microwave performance. Among them, high densification was 93.92 ± 0.35%, and the Q × f value ∼16981 ± 340 GHz at x = 0.75, was more than 2∼3 times higher than other BTN-based ceramics. Superior microwave dielectric properties were achieved for 0.75 wt% H 3 BO 3 -doped BCZTN ceramic sintered at 900°C: ε r ∼42.35 ± 0.48, Q× f ∼16981 ± 340 GHz, and τ f ∼40.02 ± 1.43 ppm/°C. More encouragingly, BCZTN-0.75HB ceramic did not chemically react with Ag, which suggested that it had the potential to be a candidate material for low-temperature co-fired ceramics base station communication devices.
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
CERAMICS INTERNATIONAL
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2026
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IF 6
Xiaolei Shi,Fuyu Li
Currently, microwave communication devices are rapidly evolving toward miniaturization, high stability, and cost-effectiveness. However, traditional microwave dielectric ceramics with moderate dielectric constants require excessively high sintering temperatures and exhibit poor microwave dielectric properties. Here, 2 wt % V 2 O 5 -modified Ba 3 Ti 4 Nb 4 O 21 (BTN) ceramic is prepared via solid-state reaction method. The sintering temperature of the BTN ceramic is successfully reduced from 1270°C to 975°C. This ceramic exhibits excellent microwave dielectric properties ( ε r = 47 (@5.78GHz), Q × f = 15,841 GHz (@5.78GHz), τ f = + 14.3 ppm/°C). Using XRD, SEM, EDS, Raman spectroscopy, and first-principles calculations, the changes in the microwave dielectric properties of BTN ceramics and their effects are elucidated. Based on this ceramic, a slot-coupled side-fed cylindrical dielectric resonant antenna was designed and investigated by full-wave electromagnetic simulation. The simulated antenna achieves excellent impedance matching and polarization isolation while maintaining a compact size: simulated center frequency is 6.74 GHz, BW = 200 MHz, and S 11 = -36.26 dB. This work demonstrates that BTN + 2 wt % V 2 O 5 microwave dielectric ceramics hold great potential for development in the field of 5G microwave communications.
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DOI
高影响因子
INORGANIC CHEMISTRY
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2024
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IF 4.3
Tingting Tang,Fangqing Ye,Huang Hua,Chaoyang Li,Jian Shen
With the rapid development of 5G communication technology, microwave dielectric ceramics with high dielectric constants are very conducive to the miniaturization of passive devices. Here, Ba3Ti4–x(Ni1/3Nb2/3)xNb4O21 (BTN ∼ NN, 0.03 ≤ x ≤ 0.15) ceramics with hexagonal phases are synthesized via the solid-phase route. The composite (Ni1/3Nb2/3)4+ ion substitution strategy can substantially improve the microwave dielectric properties of the Ba3Ti4Nb4O21 (BTN) ceramic. The εr and Q × f values depend on the ionicity (Nb–O bonds) and lattice energies (Nb(1)–O3 and Nb(1)–O2(1) bonds). The microwave dielectric properties of the BTN ∼ NN (x = 0.09) ceramic sintered at 1250 °C are εr = 60.3, Q × f = 22073 GHz, and τf = 78.1 ppm/°C. A miniaturized all-ceramic radome (@400 mm × 400 mm × 8 mm) for 5G beam-splitting function is designed and demonstrated using this ceramic. Compared to other radomes designed for other work utilizing low εr, the size of this radome has been reduced by 3/7. The reflection coefficients of the beam splitting function are all 0.73, and the phase shifts are all 360°. This work contributes to the development of miniaturized passive devices from a materials point of view.
研究领域:
材料科学
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电子工程
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DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2022
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IF 6.364
Xiaohui Wu,Qin Zhang,Fangyi Huang,Xingyu Huo,Fuyu Li,Yuanxun Li,Hua Su
New low loss and low-sintering temperature co-fired Ba 3- x Cu x Ti 4 Nb 4 O 21 (BCTN, 0 ≤ x ≤ 0.12) ceramics with 0.60 wt % Li 2 O-B 2 O 3 -SiO 2 -CaO-Al 2 O 3 (LBSCA) glass were prepared by solid-state reaction methodology. This work showed that CuO and LBSCA were effective sintering aid, which improved the densification and decreased sintering temperature . Thus, the excellent microwave dielectric properties of BCTN ceramics ( x = 0.08) were obtained after sintering at 925 ℃ with ε r ~ 44.18, Q× f ~ 17,860 GHz (@ 5.6 GHz) and τ f ~ 94.76 ppm/℃. Q× f value was increased nearly 3-fold compared to pure BTN ceramics (~ 6090 GHz). Based on the P-V-L bond theory, the Ti-O and Nb-O bonds together contributed greatly to ε r . The Nb-O bonds was the main factor affecting the internal loss on Q× f . The τ f closely related to the oxygen octahedron [Ti1/Nb1O 6 ]. The BCTN ceramics would not react with Ag electrodes, and had great potential to be used in LTCC microwave devices.
研究领域:
材料科学
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电子工程
✓ 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）