JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2023
·Vol. 34
·期 2
·1-12
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IF 2.8
Su Qi,Qu Jing-Jing,Liu Fei,Feng Ai-lin,Yuan Chang-Lai,Liu Xiao,Meng Liu-Fang,Ding Guo-An,Su Ming-wei,Chen Guo-Hua
A series of new systems of the SrCe 1- x Ti x O 3 and SrCe 1− x Zr x O 3 (SCT x and SCZ x , x = 0.0–0.1) ceramics have been prepared by the traditional solid-phase methods. The XRD patterns results show that an ABO 3 -type perovskite structure of the SrCeO 3 ceramic can be obtained as x = 0.0. With the increase in Ti 4+ - and Zr 4+ -ions-doping content of x = 0.02–0.1, the SCT x and SCZ x ceramics basically belong to the perovskite phase with the orthorhombic structure of the space group Pmcn (62), and the results of EDS analysis on the proportion of each element can also verify the correctness of the XRD analytical results. In addition, all the microstructures are dense for the SCT x and SCZ x ( x = 0.0–0.1) samples. The fitting results of complex plane impedance verified that the temperature stability of SCT x solid solution ceramics is more suitable for adjusting to the practical application range. Especially, the SCT x ( x = 0.03) ceramics sintered at 1270 °C for 4 h can obtain the relatively excellent dielectric properties of ε r = 50.16, Q × f = 8,940 GHz (at 5.91 GHz), and τ f = + 0.08 ppm/°C.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
·
IF 6.3
Tao Wang,Jian Zou,Jun Yang
The optical properties of colored cool pigments including their color and solar reflectance are predominantly governed by chemical defects.In this study, a series of yellow cool pigments SrCe 1-x Tb x O 3 (x = 0–0.3) and SrCe 0.7-x Tb 0.3 Y x O 3 (x = 0–0.1) were synthesized via the solid-state reaction based on defect engineering. The effects of chemical defects on their optical performance were systematically investigated. Tb doping extends the absorption edge of the pigments to the visible region beyond 500 nm, thereby imparting a distinct yellow hue to the pigment. However this doping process simultaneously introduces oxygen vacancy defects and facilitates the coexistence of mixed-valence cations (Ce 4+ /Ce 3+ and Tb 4+ /Tb 3+ ) within the host lattice. This results in pronounced tail absorption that compromises both color properties and solar reflectance. To address this issue, yttrium was introduced as a co-dopant following the charge compensation principle which effectively suppressed defect formation and reduced tail absorption intensity. This co-doping strategy successfully achieved a synergistic optimization of pigment color and solar reflectance. The optimized pigments exhibited a high b* value of 75 and an exceptional near-infrared reflectance of95.33 %. The simulation experiment revealed that coating based on the as-prepared pigment exhibited an internal surface temperature reduction of 15.5 °C compared to the conventional cement coating. These findings underscore that optimizing color and solar reflectance through chemical defect regulation represents a feasible approach for preparing high-performance colored cool pigments.
研究领域:
材料科学
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光学性能
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固态化学
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陶瓷颜料
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节能涂层
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2025
·
IF 4.3
Fengjuan Liu,Yan Zhang,Tingting Wang,Peng Jiang,Bei Liu,Yunxia Wen,Ning Qu,Jie Kong,Zhenchen Tang,Feng Zeng,Han Lin,Xiaohua Lu,Tuo Ji,Jiahua Zhu
The strong N N bond, notoriously difficult to dissociate, has long posed a significant challenge to ammonia synthesis under mild conditions, typically requiring high temperatures and pressures. Here, Ru-supported Sr-based perovskite/CNT core/shell composites were developed as microwave-responsive catalysts for ammonia synthesis. Leveraging their exceptional microwave responsiveness, Ru/SrCeO 3 /CNT achieved an NH 3 production rate of 1.04 mmol·(g·h) −1 at 300 °C and 0.1 MPa, with no deactivation observed after 72 h. The energy consumption reached 0.10 MJ·(mol·g) −1 at 30 W much lower than the recent research on microwave ammonia synthesis. The core/shell architecture facilitated in-situ heat generation from the CNT core, enhancing interfacial reactions on Ru nanoparticles. Furthermore, XPS and H 2 -TPR analyses revealed that oxygen vacancies and strong interfacial interactions in the SrCeO 3 support boosted the electron-donating capacity of Ru active sites, promoting N N bond cleavage. This work offers a scalable, energy-efficient strategy for sustainable ammonia production.
研究领域:
催化化学
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材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2023
·Vol. 13
·期 6
·955
·
IF 2.7
Qi Su,Jingjing Qu,Fei Liu,Changlai Yuan,Xiao Liu,Mingwei Su,Liufang Meng,Guohua Chen
Ti4+-ion-doped (n+ 1)SrO −nCeO2(n= 2) ceramic systems were prepared with the conventional solid-state reaction method, and the effects of the phase structures and compositions, sintering behaviors, microstructures and microwave dielectric properties of these ceramic systems were investigated in detail as a function of TiO2content. The analytical results of the XRD patterns show that the pure (n+ 1)SrO −nCeO2(n= 2) system is a composite-phase ceramic system with coexisting SrCeO3and Sr2CeO4phases (represented as a SrCeO3+ Sr2CeO4system), which belong to the orthogonal structures of the Pmcn (62) and Pbam (55) space groups, respectively. For thexTiO2-(1 − x) (SrCeO3+ Sr2CeO4) (x= 0.1–0.4) ceramic samples, the secondary phase Sr2TiO4can also be detected within the range of the investigated components. Meanwhile, the Raman spectroscopy, SEM-EDS, and HRTEM (SAED) analysis results also verified the correctness and consistency of the phase structures and compositions for all the given specimens. In addition, complex impedance spectroscopy was used to detect the conductive behavior of these compound ceramic systems, and the calculation results show that the appropriate addition of Ti4+-ions can make the SrCeO3+ Sr2CeO4system have better thermal stability. The composition ofx= 0.2 multiphase structural ceramic sample sintered at 1330 °C for 4 h has a near zero τfvalue of ~−4.6 ppm/°C, a moderateεrof ~40.3 and a higherQ×f~44,020 GHz (at 6.56 GHz). The relatively superior-performing ceramics developed in this work are expected to provide a promising microwave dielectric material for communication components.Keywords:phase structures and compositions;SrCeO3+ Sr2CeO4system;TiO2addition;microwave dielectric properties
研究领域:
材料科学
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陶瓷学
✓ 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）