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Katsumata, Tetsuhiro*; Suzuki, Ryo*; Sato, Naoto*; Oda, Ryoya*; Motoyama, Shingo*; Suzuki, Shumpei*; Nakashima, Mamoru*; Inaguma, Yoshiyuki*; Mori, Daisuke*; Aimi, Akihisa*; et al.
Chemistry of Materials, 36(8), p.3697 - 3704, 2024/04
A perovskite-type oxynitride BaFeOF was prepared by high-pressure synthesis. Since the SHG signal was observed in the obtained material, suggesting the existence of spontaneous polarization, the mechanism of polarization was investigated by synchrotron high-energy X-ray diffraction. The obtained pair distribution functions were fitted, and a local polarization mechanism with different orientations was found. Since BaFeO
F is also a magnetic material, a magnetic domain and a ferroelectric domain are considered to coexist.
Yoneda, Yasuhiro; Tsuji, Takuya; Matsumura, Daiju; Okamoto, Yoshihiro; Takaki, Seiya; Takano, Masahide
Physica B; Condensed Matter, 663, p.414960_1 - 414960_9, 2023/08
Times Cited Count:0 Percentile:0.00(Physics, Condensed Matter)We performed various synchrotron X-ray measurements to extract local and average structures of DyN-ZrN solid solutions. We performed the nanoscale structural analysis by combining X-ray absorption fine structure and high-energy X-ray diffraction. The DyN-ZrN solid solution has a rock-salt type cubic crystal structure, and there are instabilities such as the chemical order of the metal site and the distribution of the bond length of the nitrogen site.
Yoneda, Yasuhiro
JSAP Review (Internet), 2023, p.230202_1 - 230202_7, 2023/00
It is important to determine whether a sample is a single phase or not in order to improve the quality of ferroelectrics. Therefore, we have succeeded in developing a detection method for trace amounts of segregated phases by using two-body correlation distribution function (PDF) in addition to X-ray diffraction, which has been conventionally used to detect impurities. In the X-ray diffraction pattern of the BaTiO-BiFeO
solid solution, it appears as a single phase with a rhombohedral structure. However, when the PDF was calculated from the obtained diffraction pattern, it was found that not only the component derived from the rhombohedral crystal structure calculated from the average structure but also the BaTiO
component was mixed and segregated. By using PDF in this way, it has become possible to detect fine segregation phases on the order of nanoscale.
Yoneda, Yasuhiro
Oyo Butsuri, 91(12), p.729 - 735, 2022/12
It is important to determine whether a sample is a single phase or not in order to improve the quality of ferroelectrics. Therefore, we have succeeded in developing a detection method for trace amounts of segregated phases by using two-body correlation distribution function (PDF) in addition to X-ray diffraction, which has been conventionally used to detect impurities. In the X-ray diffraction pattern of the BaTiO-BiFeO
solid solution, it appears as a single phase with a rhombohedral structure. However, when the PDF was calculated from the obtained diffraction pattern, it was found that not only the component derived from the rhombohedral crystal structure calculated from the average structure but also the BaTiO
component was mixed and segregated. By using PDF in this way, it has become possible to detect fine segregation phases on the order of nanoscale.
Yoneda, Yasuhiro; Kim, S.*; Mori, Shigeo*; Wada, Satoshi*
Japanese Journal of Applied Physics, 61(SN), p.SN1022_1 - SN1022_10, 2022/11
Times Cited Count:1 Percentile:14.73(Physics, Applied)Local structural analysis of the (1-) BiFeO
-
BaTiO
solid solution was performed by PDF analysis of the data obtained in the synchrotron radiation high-energy X-ray diffraction experiment. First, when XAFS experiments were performed and sample screening was performed, it was found that structural fluctuations were large in the BiFeO
-rich composition. Therefore, PDF analysis of a sample with BiFeO
-rich composition was performed. As a result, it was found that although the average structure is a cubic structure, the local structure can be reproduced with a rhombohedral crystal structure, and there is a displacement that breaks the symmetry of the rhombohedral structure in a composition with a large fluctuation.
Kyono, Atsushi*; Yamamoto, Genichiro*; Yoneda, Yasuhiro; Okada, Satoru*
Isotope News, (783), p.23 - 27, 2022/10
Mineral traps are attracting attention as an underground storage method for carbon dioxide. Carbon dioxide laden groundwater reacts with basalt to form magnesite. The formed magnesium carbonate phase varies in many ways, but we tried to clarify the structure because all of them pass through amorphous magnesium carbonate. Pair distribution function using high-energy X-ray diffraction revealed that amorphous magnesium carbonate has a structure similar to that of hydromagnesite. It can be said that it is a safe sequestration method as a carbon dioxide storage technology.
Yagi, Yutaro*; Wakita, Yudai*; Kagomiya, Isao*; Matsue, Ikuya*; Kakimoto, Kenichi*; Matsumura, Daiju; Yoneda, Yasuhiro
ChemistrySelect (Internet), 7(21), p.e202104575_1 - e202104575_7, 2022/06
Times Cited Count:0 Percentile:0.00(Chemistry, Multidisciplinary)Nakashima, Koichi*; Hironaka, Kota*; Ouchi, Kazuma*; Ajioka, Mao*; Kobayashi, Yoshio*; Yoneda, Yasuhiro; Yin, S.*; Kakihana, Masato*; Sekino, Toru*
ACS Omega (Internet), 6(48), p.32517 - 32527, 2021/12
Times Cited Count:5 Percentile:35.86(Chemistry, Multidisciplinary)The BaTiO nanoparticles synthesized by the hydrothermal method is examined by synchrotron X-ray and TEM observation. It was found that the particle size of synthesized BaTiO
depends on the particle size of the raw material of TiO
. Succeeded in synthesizing 100 nm size BaTiO
nanocrystals showing uniform particle size distribution using TiO
nanoparticles with optimized particle size. The obtained BaTiO
nanocrystal is a tetragonal system of ferroelectric phase. A three-dimensional structure of BaTiO
nanoparticles could be obtained by the electron beam tomography.
Yoneda, Yasuhiro; Noguchi, Yuji*
Japanese Journal of Applied Physics, 60(SF), p.SFFA08_1 - SFFA08_10, 2021/11
Times Cited Count:4 Percentile:34.55(Physics, Applied)BiNa
TiO
(abbreviated as BNT) is a lead-free material but exhibits relatively large piezoelectric properties, a lot of researches have been conducted. We performed local structural analysis using high-quality BNT with a stoichiometrically correct composition, and found a chemical order structure of Bi/Na in locally. BNT undergoes a phase transition to a cubic phase at 400
C. We estimated that a new disorder structure will appear in the high-temperature phase. In the high temperature phase, pair distribution function (PDF) analysis using synchrotron radiation high-energy X-rays was performed. As a result, we found that Bi shifts from 200
C, and this shift becomes an order parameter for the phase transition.
Yoneda, Yasuhiro; Ohara, Koji*
Fummatsu X-sen Kaiseki No Jissai, Dai-3-Han, p.272 - 286, 2021/08
In recent material development, not only conventional crystal structure analysis but also pair distribution function (PDF) analysis is increasingly used. This chapter (Chapter 15) deals with PDF analysis of crystalline materials using data obtained from synchrotron radiation powder X-ray diffraction experiments.
Nakashima, Koichi*; Onagi, Kaito*; Kobayashi, Yoshio*; Ishigaki, Toru*; Ishikawa, Yoshihisa*; Yoneda, Yasuhiro; Yin, S.*; Kakihana, Masato*; Sekino, Toru*
ACS Omega (Internet), 6(14), p.9410 - 9425, 2021/04
Times Cited Count:9 Percentile:57.40(Chemistry, Multidisciplinary)We succeeded in synthesizing barium titanate nanocubes by hydrothermal synthesis. When the nanocubes were examined in detail using a scanning electron microscope, pulsed neutrons, and large synchrotron radiation, it was found that a reconstituted layer of titanium oxide was formed on the surface.
Yoneda, Yasuhiro; Taniguchi, Hiroki*; Noguchi, Yuji*
Journal of Physics; Condensed Matter, 33(3), p.035401_1 - 035401_8, 2021/01
Times Cited Count:4 Percentile:31.62(Physics, Condensed Matter)Nanoscale structural analysis of relaxor Pb(MgNb
)O
(PMN) was performed using synchrotron high-energy X-ray diffraction measurements. Although PMN is a well-known relaxor ferroelectric material, the average structure is a cubic structure, and various models have been proposed to explain the ferroelectric microstructure. We performed a wide-range local structure analysis up to 20 nm using the pair distribution function (PDF). As a result, it was found that the structure of PMN changed depending on the distance and it was a glass-like structure.
Yoneda, Yasuhiro; Noguchi, Yuji*
Japanese Journal of Applied Physics, 59(SP), p.SPPA01_1 - SPPA01_7, 2020/11
Times Cited Count:19 Percentile:76.63(Physics, Applied)We investigate A-site cation ordering in the ferroelectric perovskite BiNa
TiO
(BNT) by synchrotron X-ray total scattering. Although BNT has a problem of a low depolarization temperature, it is promising a lead-free piezoelectric material. Since the depolarization temperature is presumed to correspond to a relaxer like gradual order-disorder phase transition, local structure analysis is necessary to understand the structure of the diorder phase. Through this approach, the elusive connection between chemical heterogeneity and structural heterogeneity is revealed. Because of the large randomness, the Ti off-center shift is averaged out beyond the unit cell and the structure becomes very close to the average structure beyond the unit cell.
Yoneda, Yasuhiro; Yoshigoe, Akitaka; Takeda, Yukiharu; Shiwaku, Hideaki; Matsumura, Daiju; Shobu, Takahisa; Tamura, Kazuhisa
Materia, 58(12), p.763 - 769, 2019/12
This is an introduction to the equipment provided for each implementation period belonging to the structure analysis platform in the nanotechnology platform.
Yoneda, Yasuhiro; Kunisada, Ryoichi*; Chikada, Tsukasa*; Ueno, Shintaro*; Fujii, Ichiro*; Nagata, Hajime*; Ohara, Koji*; Wada, Satoshi*
Japanese Journal of Applied Physics, 58(SL), p.SLLA03_1 - SLLA03_7, 2019/11
Times Cited Count:4 Percentile:21.16(Physics, Applied)Katsumata, Tetsuhiro*; Suzuki, Ryo*; Sato, Naoto*; Suzuki, Shumpei*; Nakashima, Mamoru*; Inaguma, Yoshiyuki*; Mori, Daisuke*; Aimi, Akihisa*; Yoneda, Yasuhiro
Journal of Solid State Chemistry, 279, p.120919_1 - 120919_8, 2019/11
Times Cited Count:10 Percentile:55.44(Chemistry, Inorganic & Nuclear)Katsumata, Tetsuhiro*; Inaguma, Yoshiyuki*; Mori, Daisuke*; Aimi, Akihisa*; Yoneda, Yasuhiro
Seramikkusu, 54(9), p.629 - 632, 2019/09
Crystal structure analysis of ABO perovskite-type oxyfluoride were performed by using high-energy synchrotron X-ray measurement. The effect of tolerance factor appeared in the local structure. The average structure of perovskite-type oxyfluoride found to be a cubic structure in the traditional crystal structure analysis.
Yoneda, Yasuhiro; Taniguchi, Hiroki*; Kitanaka, Yuki*; Noguchi, Yuji*
Ferroelectrics, 538(1), p.57 - 62, 2019/05
Times Cited Count:5 Percentile:26.60(Materials Science, Multidisciplinary)High-energy X-ray diffraction study was performed on lead titanate (PbTiO). Short-range order structure was revealed using atomic pair-distribution function (PDF) method. In the high-temperature cubic phase, there is a large deviation between local and average structure. Especially, Pb atoms deviated from the cubic lattice framework, but establish Pb-O-Pb random network.
Yoneda, Yasuhiro; Harada, Makoto; Takano, Masahide
Transactions of the Materials Research Society of Japan, 44(2), p.61 - 64, 2019/04
We performed three-dimensional observation of simulated fuel debris using Synchrotron Computed Tomography (CT). CT was used to make the inside of fuel debris clear. The CT observation provides that a clear contrast in the zirconia rich part and concrete rich part. Zirconia heavier than concrete moved to the lower part when crystals precipitate and aggregates near the bottom surface. As a result, phase separation occurs. The phase separation is caused by the difference in the composition ratio of zirconia, and can also be observed difference in crystal growth mode by composition ratio.
Li, S.*; Toyoda, Masayuki*; Kobayashi, Yoshiaki*; Ito, Masayuki*; Ikeuchi, Kazuhiko*; Yoneda, Yasuhiro; Otani, Akira*; Matsumura, Daiju; Asano, Shun*; Mizuki, Junichiro*; et al.
Physica C, 555, p.45 - 53, 2018/12
Times Cited Count:1 Percentile:4.92(Physics, Applied)-dependence of local distortions in BaFe
As
and LiFeAs by X-ray PDF and XAFS methods. Although PDF data exhibit anomaly at the structure transition temperature, EXAFS data exhibit no anomaly. Data supporting the local orthorhombicity at 300 K in the tetragonal phase for BaFe
As
. Arguments on the origins of the 4-fold symmetry breaking in the ground average structure of the tetragonal phase.