Materials
·
2024
·Vol. 17
·期 22
·5655
·
IF 3.1
Tianyu Hao,Jing Shen,Qiaochu Peng,Jie Liu,Wenbin Hu,Cheng Zhong
This study successfully synthesized high-tetragonality barium titanate (BaTiO3) particles with a small particle size by implementing ball milling in the solid-state synthesis of BaTiO3and utilizing nanoscale raw materials. This study also addressed the issues of impurities and uneven particle size distribution that could exist in the synthesized BaTiO3particles. The crystal structure, morphology, and particle size of the synthesized BaTiO3particles have been meticulously analyzed and discussed through the use of techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and the laser particle size analyzer. BaTiO3has been successfully synthesized, exhibiting a uniform particle size with an average diameter of 170 nm and a high tetragonality value of 1.01022. This new solid-state synthesis method provided insights to avoid the impact of “size effects” during the process of electronic device miniaturization.
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
JOURNAL OF ELECTROCERAMICS
·
2023
·Vol. 50
·期 4
·97-111
·
IF 1.7
Luan Saiwei,Wang Pengfei,Zhang Lei,He Yanmei,Huang Xiong,Jian Gang,Liu Cuicui,Yu Shuhui,Sun Rong,Cao Xiuhua,Fu Zhenxiao
Ultrafine ceramic powders with high tetragonality are the fundamental for the multi-layer ceramic capacitors (MLCCs). In this study, an efficient method of atmospherically hydrothermal assisted solid-state synthesis for ultrafine BaTiO 3 particles is presented. The BaTiO 3 nanopowders with homogeneous distribution, a mean particle size ~ 260 nm and high tetragonality of 1.0095 were obtained by at the optimal parameters of hydrothermal time of 6 h, Ba(OH) 2 ·8H 2 O/BaCO 3 = 0.25/0.75 and calcination temperature of 1000 o C. XRD and HRTEM analyses revealed a “core-shell” structure of TiO 2 @BaTiO 3 formed in the first-step hydrothermal process, which reduces the diffusion distance between BaCO 3 and TiO 2 , resulting in a lower calcination temperature at the second-step solid-state reaction. Compared with pure hydrothermal and solid-state reaction processes, the atmospherically hydrothermal assisted solid-state synthesis in this study shows larger ability for improving the particle size distribution and the tetragonality, reducing defects of BaTiO 3 particles. In particular, the grain size, sintering density, and dielectric constant at the Curie temperature of BaTiO 3 ceramics are 1.93 μm, 98%, and 7066, respectively. In the solid-state reaction stage, the lattice diffusion distance from BaO to TiO 2 tends to decrease due to the formation of BaTiO 3 shells, thus, high tetragonal and relatively small particle size of BaTiO 3 powder was synthesized. This work presents a method for preparing ultrafine BaTiO 3 powders with large tetragonality for MLCCs.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
Tungsten
·
2024
·
IF 5.6
Peng Qiao-Chu,Hao Tian-Yu,Shen Jing,Liu Jie,Zhong Cheng
Barium titanate was successfully synthesized through both the solid-state method and the oxalate thermal decomposition method. The differences in tetragonality and particle size between the two methods were discussed using X-ray diffraction, scanning electron microscopy, and the laser diffraction method. The elemental content of the impurities ws characterized by an inductively coupled plasma optical emission spectrometer. Meanwhile, the influence of process parameters such as sintering temperature, aging time, and ball milling treatment on the morphology and size of powders was investigated. The results revealed that the oxalate thermal decomposition method could fabricate the BaTiO 3 with a narrow particle size distribution and high tetragonality. Additionally, ball milling treatment offered a significant advantage in reducing particle agglomeration caused by high sintering temperatures and in producing homogeneous BaTiO 3 , which was suitable for industrial production.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 11
·4191
·
IF 3.4
Tingting Wang,Xiaoxiao Pang,Bin Liu,Jie Liu,Jing Shen,Cheng Zhong
The preparation of tetragonal barium titanate (BT) powders with uniform and suitable particle sizes is a significant prerequisite for ultra-thin and highly integrated multilayer ceramic capacitors (MLCCs). However, the balance of high tetragonality and controllable particle size remains a challenge, which limits the practical application of BT powders. Herein, the effects of different proportions of hydrothermal medium composition on the hydroxylation process are explored to obtain high tetragonality. The high tetragonality of BT powders under the optimal solvent condition of water:ethanol:ammonia solution of 2:2:1 is around 1.009 and increases with the particle size. Meanwhile, the good uniformity and dispersion of BT powders with particle sizes of 160, 190, 220, and 250 nm benefit from the inhibition of ethanol on the interfacial activity of BT particles (BTPs). The core–shell structure of BTPs is revealed by different lattice fringe spacings of the core and edge and the crystal structure by reconstructed atomic arrangement, which reasonably explains the trend between tetragonality and average particle size. These findings are instructive for the related research on the hydrothermal process of BT powders.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2025
·Vol. 36
·期 9
·1-12
·
IF 2.8
Luan Saiwei,Tang Miao,Mu Hanze,Yu Jie,Wang Pengfei,Zhang Lei
Highly tetragonal BaTiO 3 nanopowder serves as a pivotal raw material for manufacturing high-performance miniaturized multilayer ceramic capacitors (MLCCs). In this study, barium acetate and tetrabutyl titanate were used as reactants, isopropanol served as the titanium source stabilizer and dispersant, and oxalic acid was employed as the precipitant to investigate the preparation process of tetragonal-phase BaTiO 3 nanopowder. The optimal process parameters were identified, and the reaction mechanism for synthesizing BaTiO 3 via oxalate co-precipitation was explored. The experimental results indicate that, with a Ba/Ti stoichiometric ratio of 1.000 and a solution pH of 2.33, following the appropriate sequence of experimental reagent additions, the precursor underwent a precipitation reaction at 25 °C. After calcination at 950 °C, BaTiO 3 powder with an average particle size of 56 nm and a tetragonality of 1.0075 was successfully synthesized. The BaTiO 3 ceramic sintered at 1250 °C exhibits a density of 96.5% and an exceptional dielectric performance, with a dielectric constant of 9369 at the Curie temperature (125 °C). This study provides valuable insights for addressing the complex hydrolysis and residual chloride ion issues associated with the chloride method.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2024
·
IF 4.5
Huifeng Xu,Pengfei Wang,Saiwei Luan,Lixia Cheng,Zhenxiao Fu,Xiuhua Cao,Lei Zhang,Shuhui Yu,Rong Sun
Conventionally, tetragonality in BaTiO 3 powder is attributed to grain size, disregarding the role of Ba/Ti ratio. However, our study reveals a significant impact of Ba/Ti ratio on tetragonality in BaTiO 3 . With an increase in Ba/Ti ratio from 0.990 to 1.010, particle size remains around 200 nm. Tetragonality initially rises from 1.006 to a maximum of 1.0092 at Ba/Ti = 1.000, then decreases to 1.005. Lower tetragonality is associated with Ba or Ti vacancies, using density functional theory (DFT), we analyzed the electron density and lattice distinction in BaTiO 3 powders. Both Ba and Ti vacancies affect lattice distortion, the Ti vacancies leading to more significant lattice expansion and lower tetragonality than Ba vacancies. Using this powder, we fabricated high-density BaTiO 3 ceramics and multi-layer ceramics capacitors (MLCCs) with X7R temperature stability (−55 to 125 °C, ±15% coefficient) and excellent reliability. This strategy has broad implications for tetragonal BaTiO 3 nanopowders and MLCCs development.
研究领域:
材料科学
·
无机非金属材料
·
电子陶瓷
·
固态化学
·
功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）