Article
Engineering, Electrical & Electronic
Pengfei Yu, Wenfei Liu, Pandeng Gao, Tingquan Shao, Shiwei Zhao, Zhao Han, Xuanbing Gu, Jiawei Zhang, Yan Wang
Summary: In this study, tetragonal barium titanate (BaTiO3) nanopowders were successfully synthesized using the sol-hydrothermal method. The effects of temperature, time, and raw materials on the properties of BaTiO3 were investigated. The optimized conditions resulted in powders with high crystallinity and tetragonal content, making them suitable as medium materials for multilayer ceramic capacitors.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Chemistry, Physical
Tingting Wang, Xiaoxiao Pang, Bin Liu, Jie Liu, Jing Shen, Cheng Zhong
Summary: The effects of different proportions of hydrothermal medium composition on the hydroxylation process were explored to obtain high tetragonality in tetragonal barium titanate (BT) powders. The optimal solvent condition of water:ethanol:ammonia solution of 2:2:1 resulted in a BT powder with a high tetragonality of 1.009, which increased with the particle size. The uniformity and dispersion of BT powders with particle sizes of 160, 190, 220, and 250 nm were improved by the inhibition of ethanol on the interfacial activity of BT particles (BTPs). The core-shell structure of BTPs was revealed, explaining the relationship between tetragonality and average particle size.
Article
Materials Science, Multidisciplinary
Xiaoxiao Pang, Tingting Wang, Bin Liu, Xiayue Fan, Xiaorui Liu, Jing Shen, Cheng Zhong, Wenbin Hu
Summary: Tetragonal barium titanate was successfully synthesized via a one-step hydrothermal method using different solvents. Ethanol/water mixed solvent promoted the formation of a tetragonal structure with smaller particle size compared to other solvents. Among all the solvents, ethanol/water was considered the optimal reaction media for high tetragonality (c/a = 1.0088) and small average particle size (82 nm), making it suitable for applications in multilayer ceramic capacitors.
INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Huiqi Zheng, Jin Chen, Meidan Que, Tai Yang, Zhikang Liu, Weihua Cai, Lingfu Yang, Xinwei Liu, Yanjun Li, Xiaofeng Yang, Yuzhao Ma, Gangqiang Zhu
Summary: The coupling of the piezoelectric effect and photocatalytic process promoted the separation of photogenerated carriers, thus increasing the piezo-photocatalytic activity. BaTiO3 nanoparticles were prepared on the Ti3C2Tx surface, and the obtained BaTiO3/Ti3C2Tx piezo-photocatalysts exhibited rapid electron transfer and a wide visible light response range. These results demonstrate that coupling piezoelectric and photocatalytic properties has broad application prospects in water pollution control.
INORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Materials Science, Ceramics
Alireza Ramezani, Hossein Abdizadeh, Mohammad Reza Golobostanfard
Summary: BaTiO3 and SrTiO3 thin films and BaTiO3/SrTiO3 lamellar composites were successfully synthesized using the sol-gel spin-coating method in this study. The morphology and band gap of the composite samples could be altered by changing the periodicity of the samples. The optical properties of the multi-stacked composites, including dielectric constant, dielectric loss, impedance, Urbach tail, extinction coefficient, and electric modulus, were also investigated.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Ceramics
Xing Ji, Yan Zhu, Xin Lian, Baoyan Fan, Xiaoyan Liu, Peng Xiao, Yunhuai Zhang
Summary: This study successfully synthesized cubic and tetragonal BaTiO3 nanocrystals by changing the ratio of water and ethanol in the solvent. It was found that hydroxylation process affects the phase transition of BaTiO3, with ethanol being catalytically oxidized by titanium atoms promoting the formation of cubic phase, while the mixed solution of ethanol and water facilitates the tetragonal phase formation.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Bo Jiang, Changhao Zhao, Peter C. Metz, Palani Raja Jothi, Benard Kavey, Linda Reven, Michael Lindner-D'Addario, Jacob L. Jones, Gabriel Caruntu, Katharine Page
Summary: The temperature-dependent local structure evolution of surface functionalized barium titanate nanocrystals is investigated, revealing that nanocubes capped with polar BF4- ligands undergo sharper ferroelectric to paraelectric phase transitions than those capped with nonpolar OA ligands and exhibit enhanced ferroelectric order.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Ning Xu, Yuan Hao, Kaiqian Jie, Shuai Qin, Hui Huang, Li Chen, Hongzhan Liu, Jianping Guo, Hongyun Meng, Faqiang Wang, Xiangbo Yang, Zhongchao Wei
Summary: This paper introduces a novel electrically-driven zoom metalens (EZM) utilizing the electro-optic effect to accurately control the phase distribution, achieving high-speed zooming and ultra-compact design. This metalens can be widely applied in fields requiring precise beam focusing and zoom imaging.
Article
Nanoscience & Nanotechnology
Farnaz Safi Samghabadi, Long Chang, Mohammad Khodadadi, Karen S. Martirosyan, Dmitri Litvinov
Summary: In this study, cobalt ferrite/barium titanate particulate composites with high magnetoelectric coefficients were synthesized using mechanical ball milling and high-temperature annealing. The use of 50 nm cubic BaTiO3 powder as a precursor resulted in a composite with a magnetoelectric coupling coefficient value as high as 4.3 mV/Oe cm. The Microstructure of these composites differs significantly from those synthesized using 200 nm tetragonal BaTiO3 powder, showing larger CoFe2O4 grains and better electrical insulation due to the surrounding BaTiO3 matrix.
Article
Materials Science, Coatings & Films
Yu-Zhen Zheng, Huan-Ping Teng, Fu-Hsing Lu
Summary: Al-doped barium titanate thin films were synthesized using a hydrothermal-galvanic couple (HT-GC) method, exhibiting higher residual polarization and piezoelectric coefficient, suitable for technological applications in piezoelectric and triboelectric materials.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Materials Science, Ceramics
R. A. Surmenev, R. V. Chernozem, A. G. Skirtach, A. S. Bekareva, L. A. Leonova, S. Mathur, Yu. F. Ivanov, M. A. Surmeneva
Summary: The study investigated the effects of varying properties of 1D barium titanate nanostructures on ion exchange processes and phase formation. It was found that BaTiO3 nano- and microrods with surface nanomaces and nanoparticle aggregates could be formed within specific temperature, time, and alkalinity ranges. X-ray diffraction and Raman spectroscopy analyses revealed improvements in material purity and phase composition control with increasing alkalinity and synthesis time.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Physical
Marin Cernea, Mihail Secu, Roxana Radu, Paul Ganea, Vasile Adrian Surdu, Roxana Trusca, Eugenia Tanasa Vasile, Elisabeta Corina Secu
Summary: The study synthesized polycrystalline Ba1-xTbxTiO3 materials and analyzed their photoluminescence and dielectric properties, revealing that increasing terbium content reduces Curie temperature and increases phase transition diffuseness. UV-vis reflectance spectra showed a decrease in band gap energy with higher Tb content, while photoluminescence spectra demonstrated terbium enhances photoluminescence accompanied by self-trapped exciton emission.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Electrochemistry
Mukhlis M. Ismail, Odi N. Salman, Thamir Hassen Ali
Summary: In this study, BST nanorods were successfully prepared via hydrothermal method and deposited on TiO2 substrate with film transfer completed. The BST nanorods showed regular tetragon-like shape and specific vibration bands in FESEM images and FTIR spectra. The band gap of the BST nanorod films decreased as the reaction time of the prepared TiO2 nanorods increased.
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Soujanya Neti, Anupama Rani Nanmangalam, Chinna Narasimhulu Chintakuntla, Tamilselvi Ramasamy, Sanjay Sankaranarayanan
Summary: Strontium titanate nanocubes (ST NCs) with high photocatalytic activity were synthesized via a simple hydrothermal technique. The samples were characterized using advanced analytical tools, and the crystal structure, morphology, composition, and optical characteristics were analyzed. The photocatalytic activity of the samples was tested using methylene blue dye, and the results showed that ST NCs grown at 210 degrees C exhibited a degradation rate of about 94% in 90 minutes. The ST NC electrode also showed high specific capacitance, indicating its potential in energy-related applications.
INORGANIC CHEMISTRY COMMUNICATIONS
(2023)
Article
Materials Science, Ceramics
Zhe Qiao, Shujing Li, Yuanbing Li, Zhi Tu
Summary: Barium zirconate powders were synthesized via a hydrothermal reaction using a mixture of barium hydroxide and zirconium oxychloride. The reaction time and NaOH concentration were found to significantly influence the morphology and size of the particles. Prolonged reaction times promoted phase formation and improved particle crystallinity, while increasing NaOH concentration resulted in a transformation of particle morphology and improved dispersibility, with optimal results observed at 2.0mol/L NaOH concentration.
CERAMICS INTERNATIONAL
(2022)
Article
Physics, Applied
Hiroki Itasaka, Ken-ichi Mimura, Masayuki Nishi, Kazumi Kato
APPLIED PHYSICS LETTERS
(2018)
Editorial Material
Physics, Applied
Norifumi Fujimura, Yoshihiro Kuroiwa, Akira Ando, Yasuo Cho, Makoto Iwata, Ken-ichi Kakimoto, Kazumi Kato, Hajime Nagata, Masaru Shimizu, Takaaki Tsurumi
JAPANESE JOURNAL OF APPLIED PHYSICS
(2018)
Article
Materials Science, Ceramics
Yoshitake Masuda, Kazumi Kato, Masahito Kida, Jun Otsuka
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY
(2019)
Article
Chemistry, Physical
Tetsuya Hori, Qiang Ma, Kazuyo Kobayashi, Masahiro Nagao, Shinya Teranishi, Takashi Hibino
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2019)
Article
Chemistry, Multidisciplinary
Satoshi Suehiro, Teiichi Kimura, Makoto Tanaka, Seiji Takahashi, Ken-ichi Mimura, Kazumi Kato
Article
Physics, Applied
Yoko Takada, Ken-ichi Mimura, Zheng Liu, Kazumi Kato
JAPANESE JOURNAL OF APPLIED PHYSICS
(2019)
Article
Chemistry, Multidisciplinary
Yoshitake Masuda, Junji Akimoto, Kazumi Kato
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
(2020)
Article
Engineering, Electrical & Electronic
Yuji Ando, Hidemasa Takahashi, Qiang Ma, Akio Wakejima, Jun Suda
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2020)
Article
Nanoscience & Nanotechnology
Hiroki Itasaka, Ken-ichi Mimura, Kyuichi Yasui, Koichi Hamamoto, Kazumi Kato
Summary: In this study, Raman spectroscopy and scanning microwave impedance microscopy were used to investigate the internal stress and relative permittivity of BaTiO3 nanocube three-dimensional assemblies under different heat treatment temperatures. The results show that heat treatment caused internal compressive stress in the nanocube assemblies and a positive correlation between the internal compressive stress and relative permittivity.
Article
Engineering, Electrical & Electronic
Qiang Ma, Yuji Ando, Akio Wakejima
Summary: This study investigates the electron trapping behavior in GaN HEMTs on GaN substrate after bias stress, finding that the current collapse is mainly due to electron injection in the barrier layer. The time constants of electron emission are dependent on the gate quiescent bias V-gq, with multiple time constants observed.
ELECTRONICS LETTERS
(2021)
Article
Physics, Applied
Qiang Ma, Shiyo Urano, Yuji Ando, Atsushi Tanaka, Akio Wakejima
Summary: The impact of SiN film stress on the electroluminescence of AlGaN/GaN HEMTs was reported in this study, with changes in EL color and intensity observed as the stress varied. Current collapse in the HEMTs was found to worsen with increased SiN film stress and drain-to-source voltage (V (ds)).
APPLIED PHYSICS EXPRESS
(2021)
Article
Engineering, Electrical & Electronic
Qiang Ma, Shiyo Urano, Atsushi Tanaka, Yuji Ando, Akio Wakejima
Summary: This paper investigates the bias-dependence of electroluminescence in an AlGaN/GaN HEMT fabricated on a SiC substrate. The results show that as the drain voltage increases, the color of the electroluminescence changes from low-intensity red to high-intensity white, accompanied by a shift in the location of the emission from the gate to the drain edge.
IEEE JOURNAL OF THE ELECTRON DEVICES SOCIETY
(2022)
Article
Physics, Applied
Qiang Ma, Tomoyo Yoshida, Yuji Ando, Akio Wakejima
JAPANESE JOURNAL OF APPLIED PHYSICS
(2020)
Article
Materials Science, Ceramics
Yoko Takada, Ken-ichi Mimura, Kazumi Kato
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN
(2018)
Article
Materials Science, Ceramics
Ken-ichi Mimura, Kazumi Kato
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN
(2018)
