Micromachines
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2023
·Vol. 14
·期 9
·1663
·
IF 3.4
Yunsheng Fu,Xianglei Yu,Li Liu,Xianjie Tang,Junpeng Li,Guoyou Gan
Low-temperature lead-free silver pastes deserve thorough investigation for sustainable development and application of MgTiO3ceramics in electronic devices. In this study, a series of Bi2O3-B2O3-ZnO-SiO2-Al2O3-CaO glasses with suitable softening temperatures were prepared via melt quenching using a type of micrometer silver powder formed by silver nanoparticle aggregates. The composite pastes containing silver powder, Bi2O3glass powder and an organic vehicle were then screen-printed. The effects of glass powder concentration and sintering temperature on the microstructure of the surface interface were also investigated. The results showed that the silver paste for microwave dielectric ceramic filters (MgTiO3) possessed good electrical conductivity (2.28 mΩ/□) and high adhesion (43.46 N/mm2) after medium temperature (670 °C) sintering. Thus, this glass powder has great application potential in non-toxic lead-free silver pastes for metallization of MgTiO3substrates.Keywords:silver paste;MgTiO3;bonding strength;low-temperature sintering
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
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yuang Chen,Yang Zou,Lili Zhao,Zijian Lei,Lixin Song
Point defect has a significant impact on the optical properties of materials. The light absorption behavior can be changed through adjusting the concentration of point defect. Here, nonequilibrium surface oxygen vacancy is firstly introduced into MgTiO 3 material and then eliminated under laser irradiation to realize an optical transformation from high absorption to high reflectivity among a wide range of wavelength. NaBH 4 low-temperature reduction treatment is conducted to control the distribution of oxygen vacancy. MgTiO 3 @MgTiO 3-x core-shell structure is fabricated through the treatment, in which disordered MgTiO 3-x with high-concentration of oxygen vacancy forms a shell covering a highly crystalline MgTiO 3 core. The reflectivity is reduced to 5 % among 400–2500 nm due to the interconduction subband absorption of the metallized disordered MgTiO 3-x shell. Research shows that the core-shell structure is beneficial for enhancing the transformation rate owing to the short diffusion distance. Remarkably, under 100 W cm −2 1064 nm laser irradiation, the nonequilibrium surface oxygen vacancy can be eliminated in a short time and the material will transform to high-reflectivity state in 1000 ms, with the reflectivity restoring to 83 %.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2021
·Vol. 8
·期 12
·125901
·
IF 1.62
Xiaodong Jia,Shuo Mao,Lin Tian,Shujiang Chen,Guohua Li,Wei Gao
Herein, magnesium metatitanate (MgTiO3) ceramics were synthesised using recycled magnesia-hercynite (MH) bricks as the raw materials to achieve solid waste reusing of cement kiln refractories. The recycled MH materials were mixed with anatase TiO2 to investigate the effect of addition of doped B2O3 during the synthesis of MgTiO3 ceramics at 1400 °C. Phase compositions and microstructural studies were performed using x-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. In addition, energy-dispersive spectroscopy (EDS) was conducted and the dielectric properties of the samples were studied. Results show that the addition of B2O3 can promote sintering, improve shrinkage, promote densification, stabilise MgTiO3 lattice, and inhibit the formation of MgTiO3. In addition, the presence of appropriate amount of B2O3 can accelerate the material diffusion and result in grain growth through the formation of intercrystalline liquid phase. Results also suggest that an increase in dielectric constant results in a decrease in dielectric loss. It was concluded that 2 wt% was the optimum amount of B2O3 required to obtain the most favourable synthesis rate of MgTiO3 (98.2%). The samples exhibited a maximum density of 3.69 g·cm−3 and excellent microwave dielectric properties at εr = 18.28 and tanδ = 0.086.
研究领域:
材料科学
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无机化学
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DOI
高影响因子
PHYSICS AND CHEMISTRY OF MINERALS
·
2025
·Vol. 52
·期 3
·1-10
·
IF 1.6
Wang Kai,Xu Jingui,Zhang Shanrong,Zhong Qifa,Zhao Wei,Fan Dawei
The equation of state of ilmenite (FeTiO 3 ) and geikielite (MgTiO 3 ) have been investigated using in situ synchrotron X-ray diffraction at high pressures up to ~ 21.8 GPa and ~ 23.0 GPa, respectively. No phase transitions were observed within the experimental pressure ranges for both samples. The pressure-volume data were fitted using the third-order Birch-Murnaghan equation of state (EoS), yielding the following results: for FeTiO 3 , the zero-pressure unit-cell volume V 0 = 312.2(1) Å 3 , the zero-pressure bulk modulus K 0 = 165(4) GPa, and its pressure derivative K ′ 0 = 6.6(6); for MgTiO 3 , V 0 = 304.17(8) Å 3 , K 0 = 157(3) GPa, and K ′ 0 = 7.3(4). Additionally, the axial compressional behavior of FeTiO 3 and MgTiO 3 were also fitted with a linearized third-order Birch-Murnaghan EoS. The axial compressibility coefficients for FeTiO 3 along the a- and c- axes are β a = 1.43(4) × 10 − 3 GPa -1 and β c = 3.17(11) × 10 − 3 GPa -1 , respectively, with an anisotropic ratio of β a : β c = 0.45: 1.00, while β a = 1.76 (7) × 10 − 3 GPa -1 and β c = 2.61(7) × 10 − 3 GPa -1 with an anisotropic ratio of β a : β c = 0.67: 1.00 for MgTiO 3 . Both FeTiO 3 and MgTiO 3 exhibit the axial compression anisotropy, of which FeTiO 3 shows stronger axial compressibility anisotropy than MgTiO 3 . Moreover, the potential influencing factors (e.g., cation radius, crystal structure, and chemical bond strength) on the bulk moduli and the anisotropic linear compressibilities of FeTiO 3 and MgTiO 3 were further discussed.
研究领域:
地球科学
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材料科学
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DOI
高影响因子
Materials Research Express
·
2023
·Vol. 10
·期 4
·045201
·
IF 2.3
Yun Chuan Liu,Li Ying Zhang,Xiang Lei Yu,Wei Chao Li,Jun Peng Li,Guo You Gan
A high-temperature conductive silver slurry containing lead-free ZnO-B2O3-SiO2 glass for metallization of ceramic MgTiO3 substrate has been prepared. The ZnO-B2O3-SiO2 glass was obtained by high-temperature melting and cold extraction with a transition temperature (Tg) of 579 °C and thermal stability (∆T) of 105 °C as an inorganic bonding phase of high-temperature conductive silver paste. Then, silver paste with different glass powder content was sintered on ceramic MgTiO3 substrate between 730 °C and 930 °C in increments of 50 °C. Characterization of the prepared materials revealed that their resistivity increases with the increase in glass powder content and decreases with the increase in sintering temperature. Sintering temperature and glass content have significant effects on the resistivity and adhesion of the thick silver film. When the silver paste with a glass content of 1.1 wt% was sintered at 830 °C for 10 min, the resulting thick silver film had a low resistivity of 1.81 μΩ·cm (1.65 μΩ·cm for silver) and a good adhesive strength of 39.4 N mm−2. During the sintering process, the glass material melts and wets the silver powder, which promotes the sintering of the silver powder to form a dense network structure and improves the electrical conductivity of the silver film. In addition, the formation of ZnTiO3 by chemical reactions between the glass and the substrate was observed, which dramatically improved the bonding strength of the silver film. Therefore, lead-free silver paste containing ZnO-B2O3-SiO2 glass powder and MgTiO3 ceramics has broad development prospects in ceramic filters.
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
·
2025
·
IF 5.6
Baolin Guo,Xiaokang Li,Yiwen Wu,Qing Yao
Microwave dielectric ceramics, as a novel electronic material, had been extensively utilized in the fabrication of radio frequency components for communication systems, including filters, dielectric antennas, and radar applications. While dry pressing remained the most prevalent method for filter fabrication, this study proposed an innovative gel casting system for manufacturing ceramic waveguide filters. The developed system employed Hydantion epoxy resin (HER) as the gelling agent, polyethyleneimine (PEI) as the curing agent, and MgTiO 3 -CaTiO 3 (MCT) ceramic powder (exhibiting dielectric properties of ε r = 20.5, Q×f = 55,000 GHz, and τ f = ±10 ppm/°C) as the dielectric material. Experimental results demonstrated that incorporating 13 wt.% Hydantoin epoxy resin with 0.7 wt.% polyacrylic acid (PAA) dispersant yields a well-dispersed ceramic slurry containing 80 wt.% solid loading. After drying, the green body was sintered at 1400 °C for 3 h at air atmosphere. This process resulted in densified samples with homogeneous microstructure and optimized microwave dielectric properties. Building upon this foundation, a fourth-order waveguide filter was designed and fabricated with a center frequency of 3.5 GHz, bandwidth of 300 MHz, and return loss exceeding 15 dB. Compared to conventional dry pressing techniques, the gel casting approach demonstrated distinct advantages in simplified processing and cost-effectiveness. Its superior near-net-shape forming capability for complex geometries proved potential applications in next-generation 5G/6G microwave devices.
研究领域:
材料科学
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电气工程
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微波技术
·
通信系统
·
陶瓷工艺
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·Vol. 44
·期 17
·21000-21003
·
IF 3.057
Jie Zhang,Zhenxing Yue,Yu Luo,Longtu Li
A cofired trilayer ceramic architecture showing as MgTiO 3 /TiO 2 /MgTiO 3 was designed to realize temperature-stable and ultrahigh- Q microwave dielectrics in the typical MgTiO 3 -TiO 2 system. The effects of TiO 2 content on the microwave dielectric properties of cofired trilayer ceramics were studied. Through the design of cofired trilayer architecture, the chemical reactions between MgTiO 3 and TiO 2 were limited within a narrow region of MgTiO 3 /TiO 2 interfaces (~ 15 µm in width), which could be beneficial for optimizing the microwave dielectric properties. Excellent characteristics of ε r ~ 18.38, Q×f value ~ 169,900 GHz and τ f ~ − 1 ppm/°C were gained for the MgTiO 3 /TiO 2 /MgTiO 3 ceramic architectures stacked with 1.63 vol% TiO 2 . The current work could serve as new strategies to develop high-performance dielectric resonators and multilayers for 5G wireless communication applications.
研究领域:
材料科学
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无机非金属材料
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电子陶瓷
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微波介质材料
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功能陶瓷
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 29
·期 15
·13005-13010
·
IF 2.324
Cao Renping,Cheng Xinyu,Zhang Fangteng,Su Lei,Chen Ting,Ao Hui,Yu Xiaoguang,Ruan Wen
A series of MgTiO 3 :Mn 4+ , MgTiO 3 :Mn 4+ , Ge 4+ , and MgTiO 3 :Mn 4+ , B 3+ phosphors are prepared by the high temperature solid-state reaction method in air. X-ray powder diffraction (XRD) patterns confirm that there is only pure phase in all samples. The samples are composed of microparticles with irregular shapes. Their excitation spectra monitored at 658 nm may be observed in the range of 200–600 nm and their emission spectra with excitation at 330 nm cover the region from 600 to 800 nm due to the 2 E → 4 A 2 transition of Mn 4+ ion. The chromaticity coordinate is (0.7233, 0.2767). The optimal Mn 4+ content is ~ 0.3% in MgTiO 3 :Mn 4+ phosphor. The luminescence intensity and quantum efficiency of MgTiO 3 :Mn 4+ phosphor may be obviously improved by adding Ge 4+ ion and H 3 BO 3 . The experimental results are helpful for the luminescence property improvement of other Mn 4+ doped materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Shuai Ma,Xiaohua Zhang,Jie Zhang,Xiaohui Zhang,Yu Liu,Chenglong Yu,Zhenxing Yue
Low-loss microwave dielectrics are of significant importance for the miniaturization and integration of microwave devices. In this paper, the ceramics of nominal composition Mgn+1TinO3n+1 (n = 3–6) are synthesized, and the correlations among their phase compositions, defect behaviors, and microwave dielectric properties are systematically investigated. The analyses indicate that the Mgn+1TinO3n+1 ceramics are a biphasic system consisting of hexagonal ilmenite-structured MgTiO3 and cubic spinel-structured Mg2TiO4. The Rietveld refinement results demonstrate that as the n value increases, the content of the MgTiO3 phase gradually increases, while that of the Mg2TiO4 phase decreases. The results of the thermally stimulated depolarization current (TSDC) indicate that the oxygen vacancy-related defects are considered to be the main types of defects in Mgn+1TinO3n+1. As the value of n increases, the increase of the MgTiO3 phases with a more stable crystal structure leads to a gradual decrease in the concentration of oxygen vacancies. The Mgn+1TinO3n+1 ceramics exhibit excellent microwave dielectric properties at n = 6: εr = 17.55, Q × f = 284,600 GHz, and τf = −46.39 ppm/°C. In addition, the relationship between the dielectric constant and the electric field distribution is solved utilizing high-frequency structure simulator (HFSS) software, and the Q × f values are also predicted. The low-frequency dielectric temperature spectra and direct current pulse charge/discharge tests show that the low-loss Mgn+1TinO3n+1 ceramics can be good candidates for microwave capacitors even when operated under high-temperature conditions.
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
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Peijun Liu,Wenjie Zhang,Da Chen,Lili Yang
Lanthanum doped MgTiO 3 (La–MgTiO 3 ; n (La): n (Mg) = 0.05:0.95) was synthesized using a sol–gel method, and a layer of this material was supported on quartz microspheres to produce La–MgTiO 3 ( x% )/SiO 2 microspheres (LMTO( x% )/SiO 2 ; where x% represents the weight fraction of La–MgTiO 3 in the microspheres). The crystal size of MgTiO 3 decreased from 43.4 nm in La–MgTiO 3 to 29.2 nm in LMTO( 20 % )/SiO 2 , and the bandgap energies increased from 3.34 eV (La–MgTiO 3 ) to 3.91 eV (LMTO( 20 % )/SiO 2 ). The supported La–MgTiO 3 contributed the most to the total surface area of the LMTO( x% )/SiO 2 microspheres; further, the specific surface area of the microspheres decreased with decreasing La–MgTiO 3 content. The photoluminescence intensity of the microspheres was significantly lower than that of La–MgTiO 3 . The activity of La–MgTiO 3 was enhanced after loading onto the quartz microspheres. The maximum photocatalytic activity was obtained using LMTO( 40 % )/SiO 2 , while the azophloxine degradation efficiency slightly decreased after five reaction cycles.
CAS / MDL:
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2022
·Vol. 19
·期 6
·3392-3402
·
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
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2016
·
IF 2.435
Jiaqi Long,Chaoyang Ma,Yuzhen Wang,Xuanyi Yuan,Miaomiao Du,Ran Ma,Zicheng Wen,Jiantao Zhang,Yongge Cao
TiO 2−x MgO: 0.1 at% Mn 4+ (1 ≤ x ≤ 2) red phosphors are synthesized through a traditional high temperature solid-state reaction method. The excitation and emission spectra indicate that 700 nm and 660 nm red emission peaks are ascribed to Mn 4+ ions doped in MgTiO 3 and Mg 2 TiO 4 , respectively. The Ti 4+ octahedron is connected in MgTiO 3 by O 2− ions of the octahedrons, while the Ti 4+ octahedron is separated in Mg 2 TiO 4 by Mg 2+ tetrahedron and Mg 2+ octahedron. This results that the quenching concentration is higher in Mg 2 TiO 4 than in MgTiO 3 leading the less luminous centers in MgTiO 3 . Detailed spectroscopic and crystal-field studies of the Mg 2 TiO 4 : Mn 4+ and MgTiO 3 : Mn 4+ is described in the present paper.
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DOI
高影响因子