JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2022
·Vol. 106
·期 1
·285-292
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IF 4.186
Mengjiao Chi,Yahan Liu,Jianwei Zhao,Chao Dong,Xinjiang Luo,Dawei Wang,Bing Liu,Minmin Mao,Feng Shi,Kaixin Song
It is difficult to get pure-phase Mg 3 B 2 O 6 (abbreviated as MBO) ceramics by the traditional high-temperature solid-state reaction method. In this paper, pure-phase MBO ceramics were successfully densified and obtained by combining the cold sintering and post-annealing process. The relative density of MBO ceramics was ∼80% cold sintered at 150°C/90 min/800 MPa, which was further improved to ∼91% by post-annealing at 900°C, 400°C lower than that of the traditional high-temperature sintering process (∼1300°C). X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and Raman results demonstrated that the secondary phase of MgO was effectively eliminated, and dense microstructure was observed by the cold-sintering process plus post-annealing treatment. Finally, the microwave dielectric properties of MBO were evaluated with ε r : 5.15–6.37, Q×f : 5942–16 686 GHz, τ f : −48.45–69.72 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
MATERIALS CHEMISTRY AND PHYSICS
·
2012
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IF 2.234
Zhi Wang,Junyu Zhu,Wenfei Xu,Jin Sui,Hui Peng,Xiaodong Tang
In this work, a facile method for the synthesis of pure phase BiFeO 3 (BFO) nanoparticles with the microwave assistance was reported. BFO nanoparticles with high pure phase can be prepared in 20 min, which is much shorter than that of the traditional hydrothermal methods . The effect of microwave heating time on the phase purity of obtained samples was investigated in detail by using X-ray diffraction (XRD). An interesting phenomenon was observed that the pervoskite-type BFO with pure phase periodically appeared during the microwave heating process. The investigation of the magnetic properties of prepared samples also revealed the periodical formation of the pure phase BFO. The sample with a microwave heating time of 20 min shows a magnetization of 1.05 emu g −1 which is in accordance with the reported value.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Yuqi Geng,Yuxiang Zhao,Fen Yue,Qingshan Zhu,Maoqiao Xiang
Si 2 N 2 O ceramic, an emerging functional and structural material, has a wide range of applications. However, the preparation of pure-phase Si 2 N 2 O powder remains challenging due to the mass transfer resistance and undesirable side reactions in the conventional methods. Herein, a novel molecular approach combined with the decomposition process has been developed to synthesize pure-phase Si 2 N 2 O powders. The hydrated Si(NH) 2 precursors were synthesized through the chemical vapor deposition (CVD) of SiCl 4 , NH 3, and humidified N 2 in a fluidized bed reactor (FBR) in two steps. Then, the hydrated Si(NH) 2 precursors were decomposed into amorphous and subsequently transformed into crystalline powders under different temperatures and time. It was found that the molar ratio of N/O of the hydrolyzed Si(NH) 2 can be controlled by N 2 ventilation time and played an important role in synthesizing high pure Si 2 N 2 O powder. When it varied from 2.5:1 to 2:1, pure-phase Si 2 N 2 O powder was obtained after heat treatment at 1300–1500 °C, which features a big tolerance for N/O ratios. This newly developed method offered a chance for the preparation of high-quality Si 2 N 2 O powder with high efficiency and low cost.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 5
·期 9
·6879-6885
·
IF 3.708
Ping An,Zhurong Liang,Xueqing Xu,Xin Wang,Hu Jin,Nan Wang,Junxia Wang,Furong Zhu
Pure phase kesterite Cu2ZnSnS4 (CZTS) nanocrystals (NCs) have been successfully synthesized via a heating-up method utilizing metal salts as cation sources and thioacetamide (TAA) as a coordinating sulphur precursor in combination with oleylamine (OAm) as a coordinating ligand and solvent. The slower release of H2S from the metal–TAA complexes, as compared with the commonly used sulphur powder, is crucial for control of the grain size and size distribution of the NCs. As dominating coordinating ligands, OAm led to Sn-rich nuclei and kesterite CZTS NCs. The formation of pure phase kesterite CZTS NCs depends significantly on the temperature and Zn2+/Sn4+ molar ratio of the reaction system. The formation mechanism of the pure phase kesterite CZTS NCs has been clarified taking into account the chemical potentials of the elements involved.
研究领域:
材料科学
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2025
·
IF 8.3
Jing-Hui Zhang,Dong-Chu Lu,Hai-Yan Mao,Shan-Lin Zhang,Cheng-Xin Li
One significant challenge of using Sr and Mg doped LaGaO 3 (LSGM) as an electrolyte for solid oxide electrochemical cells lies in attaining a high-purity phase and exceptional ionic conductivity through a straightforward and cost-effective fabrication process. This study introduces an innovative approach to synthesizing high-purity phase LSGM electrolytes by incorporating Li oxides as a phase formation additive within the conventional solid-state reaction method. The impact of Li oxides addition on the phase structure, sintering characteristics, and conductivity of LSGM electrolytes is thoroughly characterized. Results indicate that addition of 1 mol% Li completely eliminates La 2 O 3 impurities, yielding an LSGM electrolyte with a high-purity phase structure. However, increasing Li to 1.5 and 2 mol% introduces common impurities such as LaSrGa 3 O 7 and LaSrGaO 4 . Notably, the high-purity phase LSGM with 1% Li demonstrates impressive oxygen ionic conductivity. At 800 °C, the conductivity reaches 0.195 S cm −1 and shows remarkable stability across a wide range of oxygen partial pressures. Furthermore, a full cell employing a ∼200 μm high-purity phase LSGM electrolyte achieves an output power density of 1.5 W cm −2 in solid oxide fuel cell mode and a current density of 3.02 A cm −2 at 1.5 V in steam electrolysis mode at 800 °C.
研究领域:
材料科学
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能源工程
✓ 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）