2022年07月, 物質・デバイス共同研究賞 受賞, チタン酸バリウムナノキューブの合成と微構造解析, 物質・デバイス領域共同研究拠点
中島光一、小名木海飛、廣中航太、大内一真、味岡真央、殷シュウ、垣花眞人、関野徹
その他の賞

2022年06月, 無機マテリアル学会 学術賞 受賞, 溶液化学に立脚した機能性セラミックス材料のナノクリスタル合成, 無機マテリアル学会
中島光一
その他の賞

Promoted Hydride Substitution in BaTiO₃ Cubes
Kazunari Arai; Kaito Onagi; Ya Tang; Toru Ishigaki; Hiroaki Sai; Yuki Sasahara; Gabriel Caruntu; Harumi Okabe; Masaru Harada; Kouichi Nakashima; Hiroshi Kageyama, 責任著者, American Chemical Society (ACS)
Inorganic Chemistry, 2024年11月26日, ［査読有り］

Temperature-Induced Lattice Defects and Surface Reconstruction in BaTiO₃ Nanocubes
Kouichi Nakashima; Atsuya Toi; Reira Kuribara; Mikitaka Yoshida; Natsune Hasegawa; Tomoya Kobayashi; Ken Yamaguchi; Kotaro Hata, 筆頭著者, American Chemical Society (ACS)
Chemistry of Materials, 2024年08月28日, ［査読有り］

Synthesis and optical properties of tris(2,4,6-trichlorophenyl)methyl-type luminescent radicals bearing multiple carbazole substituents
Peiyuan Yang; Masakazu Nagata; Hiroki Fukumoto; Kouichi Nakashima; Takuma Yasuda; Tomohiro Agou, Abstract

Two tris(2,4,6-trichlorophenyl)methyl (TTM)-type luminescent radicals, TTM-(3PCz)2 and TTM-(3PCz)3, bearing 2 and 3 9-phenylcarbazol-3-yl (3PCz) substituents, respectively, were synthesized and characterized. The photobleaching of these radicals was suppressed compared with that of previously reported TTM-type luminescent radicals, suggesting a favorable effect of the multiple electron-donating 3PCz groups on the photostability of the TTM-type radicals., Oxford University Press (OUP)
Bulletin of the Chemical Society of Japan, 2024年04月15日, ［査読有り］

〔主要な業績〕Synthesis of BaTiO3–CaTiO3 and BaTiO3–SrTiO3 Core–Shell Nanocubes via the Surface Reconstruction of BaTiO3 Nanocubes　　　　　　　　　　　　　　　
Kouichi Nakashima; Hikaru Takahama; Mikitaka Yoshida; Ken Yamaguchi; Kotaro Hata
Inorganic Chemistry, 2024年01月08日, ［査読有り］

〔主要な業績〕Atomic arrangement analysis and crystal growth mechanism of HAp nanocrystal synthesized from amorphous calcium phosphate　　　　　　　　　　　　　　　
Kouichi Nakashima; Sakino Misawa; Yoshio Kobayashi; Toru Ishigaki; Yoshihisa Ishikawa; Shu Yin; Masato Kakihana; Tomoyo Goto; Tohru Sekino
Journal of the American Ceramic Society, 2023年12月25日, ［査読有り］

〔主要な業績〕A Sillén Oxyhalide SrBi3O4Cl3 as a Promising Photocatalyst for Water Splitting: Impact of the Asymmetric Structure on Light Absorption and Charge Carrier Dynamics　　　　　　　　　　　　　　　
Hajime Suzuki; Daichi Ozaki; Yusuke Ishii; Osamu Tomita; Daichi Kato; Shunsuke Nozawa; Kouichi Nakashima; Akinori Saeki; Hiroshi Kageyama; Ryu Abe
Journal of Materials Chemistry A, 2023年05月, ［査読有り］

Improved photocatalytic O2 evolution on a Sillen-Aurivillius perovskite oxychloride Bi6NbWO14Cl by Rh2O3 additives and surface modifications　　　　　　　　　　　　　　　
Hajime Suzuki; Takanori Takashima; Osamu Tomita; Tomoki Kanazawa; Shunsuke Nozawa; Kosaku Kato; Akira Yamakata; Kouichi Nakashima; Akinori Saeki; Ryu Abe
The Journal of Physical Chemistry C, 2023年04月24日, ［査読有り］

Silica-coating of Ca14Al10Zn6O35:Mn4+ particles and their luminescence properties　　　　　　　　　　　　　　　
Yukina Kobayashi; Michi Nagatsuka; Keisuke Akino; Noriko Yamauchi; Kouichi Nakashima; Tomoya Inose; Chihiro Nishidate; Keisuke Sato; Kohsuke Gonda; Yoshio Kobayashi
Advanced Poeder Technology, 2023年03月07日, ［査読有り］

Boron complexes of π-extended nitroxide ligands exhibiting three-state redox processes and near-infrared-II (NIR-II) absorption properties　　　　　　　　　　　　　　　
Marika Nakamura; Risa Hyakutake; Shogo Morisako; Takahiro Sasamori; Yoshiyuki Mizuhata; Norihiro Tokitoh; Kouichi Nakashima; Hiroki Fukumoto; Tomohiro Ago
Dalton Transactions, 2022年08月, ［査読有り］

Oxidation control of metallic zinc nanoparticles by silica coating　　　　　　　　　　　　　　　
Satoru Furukawa; Noriko Yamauchi; Kouichi Nakashima; Ken-Ichi Watanabe; Hidekazu Koda; Hiroshi Kunigami; Hideki Kunigami; Yoshio Kobayashi
Materials Research Innovations, 2022年08月, ［査読有り］

Development of methods for fabricating nanoparticles composed of magnetite, gold, and silica toward diagnostic imaging
Yukina Kobayashi; Michi Nagatsuka; Keisuke Akino; Noriko Yamauchi; Kouichi Nakashima; Tomoya Inose; Chihiro Nishidate; Keisuke Sato; Kohsuke Gonda; Yoshio Kobayashi, Elsevier BV
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2022年06月20日, ［査読有り］

Controlled oxidation of metallic copper nanoparticles by a silica coating　　　　　　　　　　　　　　　
Hikaru Hayashida; Noriko Yamauchi; Kouichi Nakashima; Yoshio Kobayashi
Inorganic and Nano-Metal Chemistry, 2022年02月02日, ［査読有り］

Manipulation of charge carrier flow in Bi4NbO8Cl nanoplate photocatalyst with metal loading
Kanta Ogawa; Ryota Sakamoto; Chengchao Zhong; Hajime Suzuki; Kosaku Kato; Osamu Tomita; Kouichi Nakashima; Akira Yamakata; Takashi Tachikawa; Akinori Saeki; Hiroshi Kageyama; Ryu Abe, An efficient spatial separation of photoexcited carriers is demonstrated in a layered-oxyhalide nanoplate by controlling the direction of carrier flows upon Rh cocatalyst loading, which leads to drastic photocatalytic H₂ evolution activity., Royal Society of Chemistry (RSC)
Chemical Science, 2022年01月24日, ［査読有り］

Synthesis of metallic aluminum particles by electrolysis in aqueous solution　　　　　　　　　　　　　　　
Takefumi Hosoya; Takehiro Yonezawa; Noriko Yamauchi; Kouichi Nakashima; Yoshio Kobayashi
Micro and Nano Systems Letters, 2021年12月08日, ［査読有り］

〔主要な業績〕PbBi3O4X3 (X = Cl, Br) with single/double halogen layers as a photocatalyst for visible- light-driven water splitting: Impact of a halogen layer on the band structure and stability
Hajime Suzuki; Masanobu Higashi; Osamu Tomita; Yusuke Ishii; Takafumi Yamamoto; Daichi Kato; Tetsu Kotani; Daichi Ozaki; Shunske Noszawa; Kouichi Nakashima; Kouji Fujita; Akinori Saeki; Hiroshi Kageyama; Ryu Abe, Layered oxyhalides with a Sillén(−Aurivillius) structure have attracted considerable attention as promising photocatalysts for efficient visible-light-induced water splitting due to the elevation of the O-2p valence band maximum (VBM) derived from the strong s–p interaction between Pb/Bi-6s and O-2p electrons and the electrostatic destabilization of oxygen anions in the fluorite layers. However, the role of the halogen layer, consisting of single or double layers, was not known. In this study, we examined a Sillén-type layered oxyhalide PbBi3O4X3 (X = Cl, Br) with alternating stacks of single/double halogen layers and skeletal Bi-based oxide layers. Density functional theory (DFT) calculations of PbBi3O4X3 revealed that the two inequivalent halogen layers contribute differently to the valence band density of states; the halogen p orbitals in double layers are higher in energy and responsible for the VBM, which is understood in terms of Madelung site potentials, where the electrostatic repulsion between halide ions is at play. Another finding from the DFT calculation is the spatial separation of the conduction band minimum and the VBM based on the asymmetry of halogen layers, which may promote the charge separation. While both PbBi3O4Cl3 and PbBi3O4Br3 possess band levels appropriate for visible-light-induced water splitting, only the former showed photocatalytic O2 evolution activity. The stability of PbBi3O4Cl3 is due to the significant contribution of the O-2p orbitals to its VBM, in stark contrast to PbBi3O4Br3, where Br-4p predominately contributes to the VBM. PbBi3O4Cl3 functions as a stable O2-evolving photocatalyst in Z-scheme water splitting under visible light irradiation. These results show that the electrostatic repulsion of halogen layers is a key factor for tuning the valence band structure of oxyhalides while maintaining sufficient stability for water-splitting photocatalysis.
Chemistry of Materials, 2021年12月07日, ［査読有り］

〔主要な業績〕Optimizing TiO2 through water-soluble Ti complexes as raw material for controlling particle size and distribution of synthesized BaTiO3 nanocubes　　　　　　　　　　　　　　　
Kouichi Nakashima; Kouta Hironaka; Kazuma Oouchi; Mao Ajioka; Yoshio Kobayashi; Yasuhiro Yoneda; Shu Yin; Masato Kakihana; Tohru Sekino
ACS Omega, 2021年11月24日, ［査読有り］

Effect of silica-coating on crystal structure and magnetic properties of metallic nickel particles
Airi Tago; Noriko Yamauchi; Kouichi Nakashima; Daisuke Nagao; Yoshio Kobayashi, Elsevier BV
Advanced Powder Technology, 2021年09月11日, ［査読有り］

Fabrication of metallic copper nanoparticles by utilizing a difference in standard electrode potential　　　　　　　　　　　　　　　
Yuki Suga; Noriko Yamauchi; Kouichi Nakashima; Yoshio Kobayashi
Chemical Papers, 2021年09月06日, ［査読有り］

Preparation and properties od silica-coated metallic nickel particles
Airi Tago; Masato Yanase; Noriko Yamauchi; Kouichi Nakashima; Daisuke Nagao; Yoshio Kobayashi, Elsevier BV
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2021年09月06日, ［査読有り］

Synthesis of metallic zinc nanoparticles by reduction of zinc ions in protonic solvent　　　　　　　　　　　　　　　
Shota Noda; Noriko Yamauchi; Kouichi Nakashima; Ken-ichi Watanabe; Hidekazu Koda; Hiroshi Kunigami; Hideki Kunigami; Yoshio Kobayashi
Journal of Metastable and nanocrystalline Materials, 2021年06月15日, ［査読有り］

Fabrication of gold-immobilized quantum dots/silica core–shell nanoparticles and their multimodal imaging properties　　　　　　　　　　　　　　　
Mayu Tayama; Tomoya Inose; Noriko Yamauchi; Kouichi Nakashima; Masayuki Tokunaga; Chihiro Kato; Kohsuke Gonda; Yoshio Kobayashi
Particulate Science and Technology, 2021年06月08日, ［査読有り］

Fabrication and fluorescence imaging properties of indocyanine green-loaded poly(lactic-co-glycolic acid) nanoparticles　　　　　　　　　　　　　　　
Mayu Tayama; Tomoya Inose; Noriko Yamauchi; Kouichi Nakashima; Masayuki Tokunaga; Chihiro Kato; Kohsuke Gonda; Yoshio Kobayashi
Colloids and Polymer Science, 2021年05月24日, ［査読有り］

〔主要な業績〕Stabilization of Size-Controlled BaTiO3 Nanocubes via Precise Solvothermal Crystal Growth and Their Anomalous Surface Compositional Reconstruction　　　　　　　　　　　　　　　
Kouichi Nakashima; Kaito Onagi; Yoshio Kobayashi; Toru Ishigaki; Yoshihisa Ishikawa; Yasuhiro Yoneda; Shu Yin; Masato Kakihana; and Tohru Sekino
ACS Omega, 2021年03月29日, ［査読有り］

〔主要な業績〕Synthesis, band structure and photocatalytic properties of Sillén–Aurivillius oxychlorides BaBi5Ti3O14Cl, Ba2Bi5Ti4O17Cl and Ba3Bi5Ti5O20Cl with triple-, quadruple- and quintuple-perovskite layers
Daichi Ozaki; Hajime Suzuki; Kanta Ogawa; Ryota Sakamoto; Yoshiyuki Inaguma; Kouichi Nakashima; Hiroshi Kageyama; Ryu Abe,

New Sillén–Aurivillius layered oxychlorides with triple-, quadruple- and quintuple-perovskite layers (n = 3−5) are successfully synthesized and their photocatalytic activities are enhanced with increasing the number of the perovskite layers.

, Royal Society of Chemistry (RSC)
Journal of Materials Chemistry A, 2021年02月24日, ［査読有り］

Electrolytic synthesis of metallic zinc nanoparticles　　　　　　　　　　　　　　　
Haruna Iino; Noriko Kobayashi; Kouichi Nakashima; Ken-ichi Watanabe; Hidekazu Koda; Hiroshi Kunigami; Hideki Kunigami; Yoshio Kobayashi
Journal of Nanoparticle Reseach, 2021年02月13日, ［査読有り］

〔主要な業績〕A new lead-free Sillén–Aurivillius oxychloride Bi5SrTi3O14Cl with triple-perovskite layers for photocatalytic water splitting under visible light　　　　　　　　　　　　　　　
Daichi Ozaki; Hajime Suzuki; Osamu Tomita; Yoshiyuki Inaguma; Kouichi Nakashima; Hiroshi Kageyama; Ryu Abe
Journal of Photochemistry & Photobiology, A: Chemistry, 2020年12月10日, ［査読有り］

Development of composite nanoparticles composed of silica-coated nanorods and single nanometer-sized gold particles toward a novel X-ray contrast agent
Tomoya Inose; Takahiro Oikawa; Masayuki Tokunaga; Noriko Yamauchi; Kouichi Nakashima; Chihiro Kato; Keiichiro Hatoyama; Takashi Kamei; Kohsuke Gonda; Yoshio Kobayashi, Elsevier BV
Materials Science & Engineering B, 2020年08月28日, ［査読有り］

Synthesis of metallic zinc nanoparticles by electrolysis　　　　　　　　　　　　　　　
Ayumi Yoshida; Noriko Yamauchi; Kouichi Nakashima; Ken-ichi Watanabe; Hidekazu Koda; Hiroshi Kunigami; Hideki Kunigami; Yoshio Kobayashi
Applied Nanosience, 2020年08月05日, ［査読有り］

Synthesis of metallic copper nanoparticles in aqueous solution by sufactant-free reduction and silica coating　　　　　　　　　　　　　　　
Hikaru Hayashida; Noriko Yamauchi; Kouichi Nakashima; Yoshio Kobayashi
Chemical Papers, 2020年03月20日, ［査読有り］

Silica coating of indium phosphide nanoparticles by a sol–gel method and their photobleaching properties　　　　　　　　　　　　　　　
Masaya Kambayashi; Noriko Yamauchi; Kouichi Nakashima; Masaki Hasegawa; Yuki Hirayama; Teruaki Suzuki; Yoshio Kobayashi
SN Applied Sciences, 2019年11月08日, ［査読有り］

Solvothermal synthesis and morphology control of NaNbO3 nanocubes using a reaction medium of water and/or methanol
Nakashima, Kouichi; Toshima, Yasuharu; Kobayashi, Yoshio; Ishikawa, Yoshihisa; Kakihana, Masato, NaNbO3 particles were prepared by solvothermal synthesis at 230 degrees C in a reaction medium of either water or methanol. Morphological control of the particles was achieved by varying the synthesis conditions, such as the starting material and the reaction medium. The starting material was prepared by a process involving heat treatment of an Nb precursor at 400 degrees C and 800 degrees C. The crystal structure of the starting material depended on the heat treatment temperature, with the preferred orthorhombic Nb2O5 obtained at 800 degrees C. Large particles were obtained when water was used as the reaction medium, whereas fine particles were obtained using methanol. Under appropriate conditions, NaNbO3 nanocubes can be synthesized using orthorhombic Nb2O5 as the starting material and methanol as the reaction medium., TAYLOR & FRANCIS LTD
JOURNAL OF ASIAN CERAMIC SOCIETIES, 2019年10月, ［査読有り］

Au nanoparticles coated with chitosan
Akitoshi Tokumasu; Tomoya Inose; Noriko Yamauchi; Kouichi Nakashima; Masayuki Tokunaga; Chihiro Kato; Keiichiro Hatoyama; Takashi Kamei; Kohsuke Gonda; Yoshio Kobayashi, This paper describes a method of coating metallic gold (Au) nanoparticles with chitosan (CS) shells in an aqueous solution. A colloidal solution of Au nanoparticles with a particle size of 16.51.7nm was prepared by reducing the Au ions (III) with sodium citrate in water at 80 degrees C. CS coating was achieved in an aqueous solution containing the Au nanoparticles by using CS as a shell source and sodium hydroxide as a pH adjuster at 25 degrees C. Ultraviolet-visible extinction spectroscopy and transmittance electron microscopy observation revealed that the Au nanoparticles were coated with CS shells. Additionally, the CS shell thickness could be varied in a range up to 2.2nm by changing the CS concentration during the CS-coating process., SPRINGER
Colloids and Polymer Science, 2019年, ［査読有り］

Preparation of high‑concentration colloid solutions of metallic copper particles and their use in metal–metal bonding processes　　　　　　　　　　　　　　　
Yuki Suga; Kouichi Nakashima; Noriko Yamauchi; Yusuke Yasuda; Toshiaki Morita; Yoshio Kobayashi
SN Applied Sciences, 2019年, ［査読有り］

Fabrication and dual-modal imaging properties of quantum dot/silica coreshell particles with immobilized single-nanometer-sized gold nanoparticles
Mayu Tayama; Tomoya Inose; Noriko Yamauchi; Kouichi Nakashima; Masayuki Tokunaga; Chihiro Kato; Keiichiro Hatoyama; Takashi Kamei; Kohsuke Gonda; Yoshio Kobayashi, This work develops a process for fabricating particles composed of a quantum dot (QD) core, a SiO2 shell, and single-nanometer-sized Au nanoparticles (Au-S) immobilized on the particle surface. The QD nanoparticles were silica-coated with a sol-gel process using tetraethyl orthosilicate (QD/SiO2). A colloidal solution of the Au-S was prepared by reducing Au3+ with tetrakis(hydroxymethyl)phosphonium chloride in an aqueous solution. The QD/SiO2 particles were surface-modified with thiol groups by using (3-mercaptopropyl)trimethoxysilane (QD/SiO2/SH). The Au-S nanoparticles were immobilized on the QD/SiO2/SH particle surface by adding a colloidal Au-S solution to a colloidal QD/SiO2/SH solution (QD/SiO2/SH/Au-S). The QD/SiO2/SH/Au-S particles were surface-modified with thiol-terminated polyethylene glycol (PEG) (QD/SiO2/SH/Au-S/PEG). Fluorescence images and computed tomography (CT) images could be obtained for the colloidal QD/SiO2/SH/Au-S/PEG particle solution. The colloidal QD/SiO2/SH/Au-S/PEG particle solution had a CT value per unit concentration of Au (M) of 6.68 x 10(3) HU/M. The circulation of the QD/SiO2/SH/Au-S/PEG particles was confirmed in a mouse after injection of a colloidal particle solution into its blood vessels, and they accumulated in the heart. A portion of the QD/SiO2/SH/Au-S/PEG particles accumulated in the liver and spleen and remained there., ELSEVIER SCIENCE BV
Colloids and Surfaces A, 2019年, ［査読有り］

Electron Microscopy Observations of the Au nanorods and Au Nanorod/SiO2 Nanocapsules　　　　　　　　　　　　　　　
Kouichi Nakashima; Tomoya Inose; Takahiro Oikawa; Masayuki Tokunaga; Keiichiro Hatoyama; Masato Kakihana; Kohsuke Gonda; Yoshio Kobayashi
Journal of the Japan Society of Powder and Powder Metallurgy, 2019年, ［査読有り］

Effects of raw materials on NaNbO3 nanocube synthesis via the solvothermal method
Nakashima, Kouichi; Toshima, Yasuharu; Kobayashi, Yoshio; Kakihana, Masato, A nanocube is a single nanoscale crystal with a cubic shape. Raw materials are an important factor in determining the synthesis of nanocubes. In this study, we investigated various niobium compounds that serve as raw materials, each inducing different effects during nanocube synthesis. Perovskite sodium niobate (NaNbO3) nanocubes were synthesized using a two-step process. The first step in this process, synthesis of the raw materials, was followed by solvothermal synthesis of NaNbO3 nanocubes. The raw material for the first step was obtained by applying heat treatment to a precursor following Nb hydrolysis. The heat treatment was performed at temperatures of 300-1000 degrees C. Nb2O5 was obtained after heat treatment of its precursor, during which its crystalline system morphed into hexagonal, orthorhombic, and monoclinic systems with respective increases in temperature. For the second step, we obtained various NaNbO3 morphologies via the solvothermal method using water, methanol, or ethanol as a reaction medium. NaNbO3 nanocubes were formed by applying the solvothermal method to the synthesized precursor during heat treatment at 800 degrees C. Solvothermal synthesis was performed with methanol as the reaction medium at 200 degrees C, which resulted in the formation of NaNbO3 nanocubes., TAYLOR & FRANCIS LTD
JOURNAL OF ASIAN CERAMIC SOCIETIES, 2019年01月, ［査読有り］

Fabrication and dual imaging properties of quantum dot/silica core-shell particles immobilized with gold nanoparticles
Ting-ting Li; Tomoya Inose; Takahiro Oikawa; Masayuki Tokunaga; Keiichiro Hatoyama; Kouichi Nakashima; Takashi Kamei; Kohsuke Gonda; Yoshio Kobayashi, The present work proposes a preparation method for core-shell nanoparticles composed of quantum dots (QDs), SiO2, large Au nanoparticles (Au-L), and small Au nanoparticles (Au-s). The QDs were silica-coated with a sol-gel method using tetraethyl orthosilicate (QD/SiO2). Au-L and Au-s were fabricated by reducing Au3+ ions with sodium citrate and tetrakis(hydroxymethyl)phosphonium chloride in water, respectively. Amino groups were introduced onto QD/SiO2 surface by using (3-aminopropyl)-triethoxysilane (QD/SiO2/NH2). Both Au-L and Au-s were immobilized on QD/SiO2/ NH2 by successively reacting Au-L and Au-s with QD/SiO2/NH2 (QD/SiO2/NH2/Au-L/Au-s). Surface modification of QD/SiO2/NH2/Au-L/Au-s was performed by using polyethylene glycol (PEG) with a thiol group (QD/SiO2/NH2/Au-L/Au-s/PEG). The QD/SiO2/NH2/Au-L/Au-s/PEG colloid solution could be clearly imaged via its fluorescence. Its computed tomography (CT) value per unit concentration of Au {M) was 1.2 x 10(4) HU/M. The QD/SiO2/NH2/Au-L/Au-S/PEGs were circulated in a mouse through blood vessels, and some of them became trapped and accumulated in the liver and spleen., TAYLOR & FRANCIS LTD
Materials Technology: Advanced Performance Materials, 2018年, ［査読有り］

Silica-coating of quantum nanorods by a sol–gel process and their photo-bleaching properties　　　　　　　　　　　　　　　
Mai Yokokawa; Ting-ting Li; Masaya Kambayashi; Kouichi Nakashima; Yuki Hirayama; Hiroshi Okura; Masaki Hasegawa; Stephan Dertinger; Yoshio Kobayashi
Journal of Sol-Gel Science and Technology, 2018年, ［査読有り］

CaF2 nanocrystals synthesis that have a unique shape
Kouichi Nakashima; Joji Shibukawa; Yoshio Kobayashi; Masato Kakihana, CaF2 nanocrystals with a clear cubic shape were synthesized using both simple mixing and a hydrothermal method that neither of which required the use of surfactants or dispersants. The concentration and pH of the reaction medium, which in this case was an aqueous HNO3 solution, was found to be very important for determining the morphology of the CaF2 particles., Journal of the Japan Society of Powder and Powder Metallurgy
Funtai Oyobi Fummatsu Yakin/Journal of the Japan Society of Powder and Powder Metallurgy, 2018年, ［査読有り］

Fabrication of silica-coated gold nanorods and investigation of their property of photothermal conversion
Tomoya Inose; Takahiro Oikawa; Kyosuke Shibuya; Masayuki Tokunaga; Keiichiro Hatoyama; Kouichi Nakashima; Takashi Kamei; Kohsuke Gonda; Yoshio Kobayashi, This study described the preparation of silica-coated Au nanorods (AuNR/SiO2) in a colloidal solution, assessed their property of photothermal conversion, and investigated their ability to kill cancer cells using photothermal conversion. Au-seed nanoparticles were produced by reducing hydrogen tetrachloroaurate (HAuCl4) with sodium borohydride (NaBH4) in aqueous n-hexadecyltrimethylammonium bromide (CTAB) solution. AuNRs were then fabricated by reducing HAuCl4 and silver nitrate (AgNO3) with L-ascorbic acid in the aqueous CTAB solution in the presence of Au-seed nanoparticles. The as prepared AuNRs were washed by a process composed mainly of centrifugation to remove the CTAB. The washed AuNRs were coated with silica by mixing the AuNR colloidal solution, an aqueous solution of (3-aminopropyl)trimethoxysilane, and tetraethylorthosilicate/ethanol solution with a water/ethanol solution. We found that the addition of AuNR/SiO2 in water, in mice, and in a culture medium with cancer cells, followed by irradiation with a laser, cause an increase in temperature, demonstrating that AuNR/ SiO2 have the ability of photothermal conversion. In addition, the cancer cells in the culture medium were found to be killed due to the increase in temperature caused by the photothermal conversion. (C) 2017 Elsevier Inc. All rights reserved., ACADEMIC PRESS INC ELSEVIER SCIENCE
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 2017年03月, ［査読有り］

Electric field induced lattice strain in pseudocubic Bi(Mg1/2Ti1/2)O-3-modified BaTiO3-BiFeO3 piezoelectric ceramics
Ichiro Fujii; Ryo Iizuka; Yuki Nakahira; Yuya Sunada; Shintaro Ueno; Kouichi Nakashima; Eisuke Magome; Chikako Moriyoshi; Yoshihiro Kuroiwa; Satoshi Wada, Contributions to the piezoelectric response in pseudocubic 0.3BaTiO(3)-0.1Bi(Mg1/2Ti1/2)O-3-0.6BiFeO(3) ceramics were investigated by synchrotron X-ray diffraction under electric fields. All of the lattice strain determined from the 110, 111, and 200 pseudocubic diffraction peaks showed similar lattice strain hysteresis that was comparable to the bulk butterfly-like strain curve. It was suggested that the hysteresis of the lattice strain and the lack of anisotropy were related to the complex domain structure and the phase boundary composition. Published by AIP Publishing., AMER INST PHYSICS
APPLIED PHYSICS LETTERS, 2016年04月, ［査読有り］

Role of structure gradient region on dielectric properties in Ba(Zr,Ti)O3–KNbO3 nanocomposite ceramics
Eisuke Magome; Yoshihiro Kuroiwa; Chikako Moriyoshi; Yoshinobu Hirose; Shintaro Ueno; Kouichi Nakashima; Satoshi Wada, Crystal structures of KNbO3 (KN)/BaZrxTi1-xO3 [BZT, (0.1 <= x <= 1)] nanocomposite ceramics have been investigated using synchrotron radiation X-ray powder diffraction, where BZT nanoparticles thinly coated with KN crystals through the heteroepitaxial interface are sintered. The Rietveld analysis based on the multicomponent model reveals that the ceramic grain has the core/multishell structure consisting of a BZT core, distorted BZT and KN multishells. The variations of the volume ratio of the distorted BZT shell region corresponding to the structure gradient interface region and the dielectric property of the ceramics show similar trends as a function of x. From these results, we propose that the structure gradient region is electrically soft, and provides a crucial contribution to the dielectric properties of the nanocomposite ceramics. (C) 2015 The Japan Society of Applied Physics, IOP PUBLISHING LTD
Japanese Journal of Applied Physics, 2015年10月, ［査読有り］

Synthesis of Silver-Strontium Titanate Hybrid Nanoparticles by Sol-Gel-Hydrothermal Method
Shintaro Ueno; Kouichi Nakashima; Yasunao Sakamoto; Satoshi Wada, Silver (Ag) nanoparticle-loaded strontium titanate (SrTiO3) nanoparticles were attempted to be synthesized by a sol-gel-hydrothermal method. We prepared the titanium oxide precursor gels incorporated with Ag+ and Sr2+ ions with various molar ratios, and they were successfully converted into the Ag-SrTiO3 hybrid nanoparticles by the hydrothermal treatment at 230 degrees C in strontium hydroxide aqueous solutions. The morphology of the SrTiO3 nanoparticles is dendritic in the presence and absence of Ag+ ions. The precursor gels, which act as the high reactive precursor, give rise to high nucleation and growth rates under the hydrothermal conditions, and the resultant diffusion-limited aggregation phenomena facilitate the dendritic growth of SrTiO3. From the field-emission transmission electron microscope observation of these Ag-SrTiO3 hybrid nanoparticles, the Ag nanoparticles with a size of a few tens of nanometers are distributed without severe agglomeration, owing to the competitive formation reactions of Ag and SrTiO3., MDPI AG
NANOMATERIALS, 2015年06月, ［査読有り］

Microwave synthesis of KNbO3 nanocubes
Kouichi Nakashima; Shintaro Ueno; Satoshi Wada, Potassium niobate (KNbO3) nanocubes were obtained by microwave synthesis. The synthesis was performed using niobium oxide (Nb2O5) and potassium hydroxide (KOH) as starting materials. Water was used as the reaction medium. KNbO3 particles with perovskite structure were confirmed from X-ray diffraction (XRD). The morphology of the KNbO3 was investigated using transmission electron microscopy (TEM). KNbO3 nanocubes were synthesized by microwave synthesis at low temperature. (C) 2015 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2015年05月, ［査読有り］

Microstructures of lanthanum nickel oxide particles with crystal facets synthesized in molten chlorides
Shintaro Ueno; Yasunao Sakamoto; Hiroya Taguchi; Kouichi Nakashima; Satoshi Wada, LaNiO3 cuboid particles were successfully synthesized by the sol-gel method in the presence of molten chlorides. The precursor gels derived from the La(NO3)(3) and Ni(CH3COO)(2) solution were heated with molten chloride, NaCl or KCl, above the melting point of respective molten salts. The formation reaction of LaNiO3 was completed below the melting point of these chlorides, and then crystal growth process might be facilitated in liquid phase provided by the molten chlorides due to an increase in the mass-transportation rate. The formation of the submicron to micron-sized LaNiO3 cuboid particles, which are enclosed by {100} facets of pseudocubic perovskite, is confirmed by the electron microscope observations and the electron diffraction analysis. (C) 2015 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2015年05月, ［査読有り］

Preparation and size control of sodium niobate nanocube at various solvothermal condition　　　　　　　　　　　　　　　
Kenta Oshima; Kouichi Nakashima; Shintaro Ueno; Satoshi Wada
Transactions of the Materials Research Society of Japan, 2015年, ［査読有り］

Local structure analysis of KNbO3 nanocubes by solvothermal synthesis
Yasuhiro Yoneda; Shinji Kohara; Kouichi Nakashima; Hajime Nagata; Satoshi Wada, The atomic-scale structure of KNbO3 nanocubes synthesized by a solvothermal method has been studied using high-energy X-ray diffraction, Rietveld refinement, and the atomic pair-distribution function (PDF) technique. It was found that the local structure of KNbO3 nanocubes was rhombohedral. The rhombohedral distortion of NbO6 octahedra was maintained in the nanocubes and also observed in KNbO3 bulk ceramics. The size effect on the crystallographic structure can be understood as analogous to the temperature-driven and/or pressure-driven structural phase transitions. The tetragonal average structure of the KNbO3 nanocubes was observed as a disordered phase of the rhombohedral local structure. (C) 2015 The Japan Society of Applied Physics, IOP PUBLISHING LTD
Japanese Journal of Applied Physics, 2015年, ［査読有り］

Preparation of titanium metal/barium titanate composites with boundary layer structure and their dielectric properties
Shintaro Ueno; Yasunao Sakamoto; Hiroyuki Kakiuchi; Kouichi Nakashima; Satoshi Wada, To develop metal/insulator composite capacitors with a high effective dielectric constant, we focus on the microstructure of boundary layer (BL) capacitors. Titanium metal/barium titanate (Ti/BT) composites consisting of Ti metal grains and BT boundary nanolayers were successfully prepared from pressed Ti-BT core-shell particle compacts by a hydrothermal method below 230 degrees C. In this hydrothermal method, BT polycrystalline shell layers connected to each other by crystal growth via a dissolution and reprecipitation mechanism in barium hydroxide [Ba(OH)(2)] aqueous solutions. The thickness of BT boundary layers may increase with an increase in the Ba(OH)(2) concentration and determine electrical properties. These Ti/BT composites prepared in 250 and 500mmol/dm(3) Ba(OH)(2) solutions exhibit effective dielectric constants of over 5000 and 3000, and loss tangents below 0.075 and 0.060 in the frequency range of 100Hz-100 kHz at room temperature, respectively. (C) 2015 The Japan Society of Applied Physics, IOP PUBLISHING LTD
Japanese Journal of Applied Physics, 2015年, ［査読有り］

Microstructure and dielectric properties of silver-barium titanate nanocomplex materials by wet chemical approach　　　　　　　　　　　　　　　
Shintaro Ueno; Yasunao Sakamoto; Kouichi Nakashima; Satoshi Wada
Japanese Journal of Applied Physics, 2015年, ［査読有り］

Solvothermal synthesis of KNbO3 nanocubes using various organic solvents
Kouichi Nakashima; Shintaro Ueno; Satoshi Wada, Potassium niobate (KNbO3) nanocubes were synthesized via a solvothermal method using various organic solvents as the reaction medium. The solvothermal synthesis was conducted in different alcohols and ether-type solvents, and in mixtures of alcohol and ether-type solvents. The starting materials for the solvothermal synthesis were niobium oxide and potassium hydroxide. X-ray diffraction confirmed the presence of perovskite-structured KNbO3. The morphology of KNbO3 was investigated using scanning electron microscopy, transmission electron microscopy, and scanning transmission electron microscopy (STEM). Energydispersive X-ray (EDX) spectrometry was used to determine the elements present in the KNbO3. The KNbO3 nanocubes were the same length as the alkyl chain in the solvent that was used. The STEM and EDX analyses indicated that three elements, potassium, niobium, and oxygen, were present in the KNbO3 nanocubes, and that these elements were distributed homogeneously throughout the nanocubes. (C) 2014 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2014年07月, ［査読有り］

Low-temperature fabrication of titanium metal/barium titanate composite capacitors via hydrothermal method and their dielectric properties
Shintaro Ueno; Yasunao Sakamoto; Kouichi Nakashima; Satoshi Wada, We attempted to fabricate metal/dielectrics composite capacitors exhibiting high effective dielectric constant by a low-temperature wet chemical approach. The green compacts consisting of Ti metal particles, BaTiO3 fillers, and TiO2 precursor nanoparticles were successfully converted into Ti/BaTiO3 composite compacts by the hydrothermal method at 160 degrees C. The effective dielectric constant of these composites tends to increase with the Ti metal content and jumped up to over 10(3) near the percolation threshold. When we used the Ti(core)-BaTiO3(shell) particles as the metal component, the thin BaTiO3 shell layers covering on the Ti particles prevented the direct contact among metal particles and increases the percolation threshold. Since the effective dielectric constant of these composites depends largely on the dielectric properties of the BaTiO3 layers, it is important to control the microstructure of these composites to improve the dielectric properties of such composites. (C) 2014 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2014年06月, ［査読有り］

Preparation of Barium Titanate/Strontium Titanate Accumulation Ceramics with Necking Structure of Strontium Titanate Nanocubes
Kouichi Nakashima; Shogo Iwatsuki; Ichiro Fujii; Satoshi Wada, Barium titanate (BaTiO3) / Strontium titanate (SrTiO3) accumulation ceramics with necking structure of SrTiO3 nanocubes were prepared using a solvothermal method. XRD measurements confirmed SrTiO3 and BaTiO3 with a perovskite structure. The XRD peak intensities of the BaTiO3 increased significantly as the solvothermal reaction was repeated. After heat treatment of the SrTiO3 at 900 degrees C, the particles grew larger and formed necked contacts with each other. As the solvothermal reaction was repeated in order to coat with BaTiO3, the density increased, the porosity decreased, and the thickness of the BaTiO3 layer increased., TRANS TECH PUBLICATIONS LTD
ELECTROCERAMICS IN JAPAN XVI, 2014年, ［査読有り］

Preparation of BaZrO3 nanocrystals at low temperature
Kouichi Nakashima; Ichiro Fujii; Satoshi Wada, Barium zirconate (BaZrO3) was prepared by the composite-hydroxide-mediated (CHM) approach at low temperature. The CHM method is based on chemical reactions of materials in the eutectic hydroxide melt. In this method, the eutectic point at an sodium hydroxide (NaOH) : potassium hydroxide (KOH) molar ratio of 51.5 : 48.5 is about 165 degrees C. In the present work, the low-temperature preparation and morphology of BaZrO3 nanocrystals were investigated. Zirconium tetra-n-butoxide ((CH3CH2CH2CH2O)(4)Zr) and/or zirconium dioxide (ZrO2) were used as a zirconium source. X-ray diffraction measurements confirmed that the BaZrO3 had a perovskite structure. Barium hydroxide (Ba(OH)(2)) was used as a barium source. BaZrO3 nanoparticles were obtained when (CH3CH2CH2CH2O)(4)Zr was used as a raw material. On the other hand, BaZrO3 nanocubes were formed when ZrO2 was used as a raw material. Scanning electron microscopy and transmission electron microscopy observations indicated that BaZrO3 nanocrystals were formed., TRANS TECH PUBLICATIONS LTD
ELECTROCERAMICS IN JAPAN XVI, 2014年, ［査読有り］

Synthesis of titanium dioxide nanoparticles by solvothermal method with polymer gel
Kenta Oshima; Kouichi Nakashima; Shintaro Ueno; Satoshi Wada, Highly dispersed and homogeneous titanium dioxide (TiO₂) nanoparticles were synthesized by a solvothermal method with polymer gel. Polymer gel is essential for the highly dispersed and homogeneous nanoparticles. First, polyvinyl alcohol (PVA) was dissolved in water at 70°C and cooled to room temperature. Ammonium citratoperoxotitanate(IV) [ (NH₄)₈[Ti₄(C₆H₄O₇)₄(O₂)₄]・8H₂O] was subsequently added and dissolved in the PVA solution. Next, water was evaporated from the PVA gel using a microwave. This polymer gel and ethanol as a reaction medium were placed into the Teflon reactor of a stainless-steel autoclave with an internal volume of 100 ml. Thereafter, the autoclave was sealed and kept at 230°C for 18 h. After solvothermal synthesis, the polymer gel was collected and dissolved in water at 50°C-70°C. X-ray diffraction (XRD) measurement, scanning electron microscope (SEM), and transmission electron microscope (TEM) observations were performed for the remaining unresolved polymer gel. XRD confirmed the presence of anatase TiO₂. The crystallite particle size was estimated as 6.4 nm (D₁₀₁) from the XRD 101 peak using the Scherrer's equation. Highly dispersed and homogeneous TiO₂ nanoparticles were obtained from TEM observation with a particle distribution of 5.6 ± 1.2 nm., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Fabrication of textured ceramics using Mn and Nb-doped hexagonal BaTiO3 by an electrophoretic deposition in a high magnetic field
Eigo Kobayashi; Shintaro Ueno; Kouichi Nakashima; Nobuhiro Kumada; Tohru S. Suzuki; Tetsuo Uchikoshi; Yoshio Sakka; Yasunari Miwa; Shinichiro Kawada; Suetake Omiya; Noriyuki Kubodera; Ichiro Fujii; Satoshi Wada, (111)-oriented Mn and Nb-doped barium titanate (BaTiO₃, BT) ceramics with fine grains were fabricated with an electrophoretic deposition (EPD) method in a high magnetic field and a topotactic phase transition. Initially, accumulations of (0001)-oriented hexagonal Ba(Ti_0.95Mn_0.05)O₃ particles added with 2.5 mol%-Nb₂O₅ powder were prepared by the EPD method in the high magnetic field of 12 T. Then, the (111)-oriented, Mn and Nb-doped pseudo-cubic BT ceramics with fine grains of ～0.4 µm in diameter were obtained via the topotactic phase transition, with the degree of the (111) orientation being as high as 79 %. The piezoelectric properties of the oriented ceramics were also studied., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Preparation and characterization of KNbO3 nanocubes under various solvothermal conditions
Kouichi Nakashima; Shintaro Ueno; Satoshi Wada, Potassium niobate (KNbO₃) is a perovskite oxide functional material that has been attracting attention as dielectric materials. The present work describes the fabrication of the KNbO₃ nanocubes by wet chemical reaction. The preparation and characterization of the KNbO₃ nanocubes were investigated. KNbO₃ was prepared using a solvothermal method. 40 mL organic solvent was used such as methanol, ethanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethanol, and 2-(2-n-butoxyethoxy)ethanol while niobium oxide (Nb₂O₅) and potassium hydroxide (KOH) were used as raw materials. The reaction was performed at 230 - 250℃ for 18 h. The characterization was carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). When solvothermal syntheses were performed with various organic solvents, KNbO₃ was formed from the XRD measurement and KNbO₃ nanocubes were obtained from SEM observations. Particularly, KNbO₃ nanocubes were the smallest size when the methanol solvent was used in this study., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Low-temperature fabrication of titanium metal/barium titanate composite capacitors containing core-shell particles and their dielectric properties
Shintaro Ueno; Yasunao Sakamoto; Kouichi Nakashima; Satoshi Wada, To develop the high-volume energy storage device based on ceramic capacitors, we attempted that Ti metal particles working as internal electrodes were distributed in barium titanate (BT) layers. We compared two kinds of the metal particles; uncoated Ti metal particles and Ti-BT core-shell particles (Ti metal particles with thin BT coating layers). The green compacts consisting of the metal particles, titanium oxide precursor particles, and barium titanate fillers were successfully converted into the Ti/BT composite compacts by the hydrothermal method without heating procedure. The effective dielectric constant of these composites tends to increase with a metal content, and then drastically increases up to over 10³ near the percolation threshold (insulator-metal transition point). These dielectric constant behaviors can be explained by the percolation theory. By using the core-shell particles, the percolation threshold increases from 0.609 to 0.734, suggesting that the BT shell layers were effective to suppress the current leakage., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Solvothermal synthesis of potassium niobate/barium titanate nanocomplex ceramics with three-dimensionally connected structure-gradient region
Hideto Kawashima; Shintaro Ueno; Kouichi Nakashima; Satoshi Wada, The KN/BT nanocomplex ceramics with the necking structure were prepared by the solvothermal method to improve dielectric properties and piezoelectric response of barium titanate (BaTiO₃, BT)-based ceramics by introducing a three-dimensionally connected structure-gradient region (3D-connected SGR). We attempted to form epitaxial potassium niobate (KNbO₃, KN) layers on the sintered BT particle compacts with the necking structure by the solvothermal method at the various temperatures. The presence of the 3D-connected SGR in the KN/BT nanocomplex ceramics is suggested by the XRD measurement and the maximal dielectric constant of 1640 (at 1 MHz) and the maximal apparent piezoelectric constant, d₃₃^*, of 430 pm/V (at 0.1 Hz) were recorded for the KN/BT nanocomplex ceramics prepared at 200 °C. The introduction of the 3D-connected SGR is possible to contribute to the enhancement in the dielectric properties and the piezoelectric responses., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Preparation of Mn-doped (Bi0.5K0.5)TiO3-Bi(Mg0.5Ti0.5)O3-BiFeO3 ceramics using BiFeO3 particle synthesized by hydrothermal method and their piezoelectric properties
Harumi Kamei; Shintaro Ueno; Kouichi Nakashima; Ichiro Fujii; Yoshihiro Kuroiwa; Hisashi Minemoto; Satoshi Wada, Mn-doped 0.45(Bi_0.5K_0.5)TiO₃-0.1Bi(Mg_0.5Ti_0.5)O₃-0.45BiFeO₃ (BKT-BMT-BF) ceramics were prepared using BiFeO₃ (BF) particles synthesized by a hydrothermal synthesis as a starting material to reduce defects originating from evaporation of Bi₂O₃. X-ray diffraction patterns revealed that the synthesized BF powder and the sintered BKT-BMT-BF ceramics consisted of a single perovskite phase. The grain size of the BKT-BMT-BF ceramics was lager than that prepared by a conventional solid state synthesis. The high-field piezoelectric properties were largely improved because of de-pinning of domain walls. The remanent polarization of 24.5 μC/cm² and the apparent piezoelectric coefficient (d₃₃^*) of 268 pm/V were recorded., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Solvothermal synthesis of barium titanate nanocubes with narrow size distributions
Seiya Amano; Kouichi Nakashima; Shintaro Ueno; Satoshi Wada, Barium titanate (BaTiO₃) nanocubes were synthesized by solvothermal reaction. The synthesis was performed using barium hydroxide [Ba(OH)₂], barium acetate [Ba(CH₃COO)₂], and titanium dioxide (TiO₂) as starting materials, with Ba / Ti atomic ratio of 2.0 and Ti concentration of 0.04 mol / l. A mixture of ethanol, 2-methoxyethernol and water was added to the starting materials and this mixture was heated at 240°C for 18h in an autoclave. X-ray diffraction measurements confirmed the formation of BaTiO₃ with a perovskite structure. The water served as an oxygen source for synthesis BaTiO₃. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed cube-shaped BaTiO₃. In order to synthesize the small-scale BaTiO₃ nanocubes, various reaction conditions such as the amount of water addition, kind of barium source, and amount of barium source were investigated. BaTiO₃ nanocubes with sharp-edged corners were formed by increasing the proportion of Ba(CH₃COO)₂ used as a raw material for the barium source., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Fabrication of BaTiO3/BiFeO3 nano-complex ceramics by hydrothermal method
Yoshinobu Hirose; Shintaro Ueno; Kouichi Nakashima; Satoshi Wada, To enhance the dielectric properties of barium titanate (BaTiO₃, BT)/bismuth ferrite (BiFeO₃, BF) nano-complex ceramics by a polarization rotation mechanism like a lead zirconate titanate, we tried to introduce structure-gradient region (SGR) in the BT/BF nano-complexes by constructing epitaxial interface between BT and BF layers. The green compacts consisting of TiO₂ and BF nano-particles were hydrothermally converted into the BT/BF complexes compacts with various BT/BF molar ratios. It can be observed that the epitaxial BT layers were formed on the BF particles in the BT/BF complex with a molar ratio BT/BF=0.50 by the high-resolution transmission electron microscope. The dielectric properties of these nano-complexes tend to increase monotonically with the BT/BF molar ratio and the remarkable enhancement cannot be found despite of the formation of the BT/BF epitaxial interface. It can be considered that the displacement of Ti ions might be limited by the compressive stress on BT lattices due to the lattice mismatch at the epitaxial interface, and the dielectric properties did not enhance even if the SGR formed., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2014年, ［査読有り］

Chemical composition dependence of ferroelectric properties for BaTiO 3-Bi(Mg1/2Ti1/2)O3-BiFeO 3 lead-free piezoelectric ceramics
Ryuta Mitsui; Ichiro Fujii; Kouichi Nakashima; Nobuhiro Kumada; Yoshihiro Kuroiwa; Satoshi Wada, The BaTiO3-Bi(Mg1/2Ti1/2)O 3-BiFeO3 [ (1 - x - y)BT-xBMT-yBF] ceramics were prepared by a conventional solid-state synthesis, and their crystal structure and piezoelectric properties were investigated in details. Synchrotron X-ray diffraction (XRD) pattern revealed that a single perovskite phase was obtained for samples at x = 0.050-0.150, y = 0.465-0.735. Splitting of the (111) peak was observed when (x, y) = (0.050, 0.685) and (0.050, 0.735) indicating that crystal structure of samples changed from pseudocubic to rhombohedral phase with increasing BF content. As the BF content increased, the Curie temperature increased. The highest apparent piezoelectric constant d33 values estimated from strain (S) over the applied electric-field (E) value (d 33 = S/E) was observed at 300pm/V for the 0.325BT-0.100BMT-0.575BF ceramics at 25°C and 1 Hz. © 2013 The Ceramic Society of Japan. All rights reserved.
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan, 2013年09月, ［査読有り］

Preparation of barium titanate porous ceramics and their sensor properties
Kazuki Maeda; Ichiro Fujii; Kouichi Nakashima; Gakuyo Fujimoto; Kazuhiro Suma; Toru Sukigara; Satoshi Wada, Porous barium titanate (BaTiO3, BT) ceramics were prepared by a conventional sintering method using two kinds of BT particles. The relationship between pore structure (porosity and pore size) of BT ceramics and their sensor properties was investigated. Since a piezoelectric constant d(33) of BT depends largely on the pore structures, the microstructure control of porous BT ceramics is important to improve the figure-of-merit of piezoelectric stress sensor application (g(33)/rho). In this study, the maximal piezoelectric g(33) constant value of 14.8 x 10(-3) V.m.N-1 and the maximal g(33)/rho value of 3.14 x 10(3) V.m(4).N-1.g(-1) were obtained at a porosity of approximately 23%. (C)2013 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2013年08月, ［査読有り］

Preparation of KNbO3 nanocubes using a solvothermal method at low temperature
Kouichi Nakashima; Ichiro Fujii; Satoshi Wada, Potassium niobate (KNbO3) was prepared using a solvothermal method. The synthesis was conducted using niobium oxide (Nb2O5) and potassium hydroxide (KOH) as starting materials and ethanol as the reaction medium. X-ray diffraction (XRD) confirmed the presence of perovskite KNbO3 particles and indicated that the lattice of the KNbO3 was orthorhombic. The morphology of the KNbO3 was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and scanning transmission electron microscopy (STEM). Energy-dispersive X-ray (EDX) spectrometry was conducted with TEM/STEM, which clearly revealed that the KNbO3 particles were nanosized and possessed a cubic shape with sharp-edged corners. The STEM-EDX observations indicated that all three elements of potassium (K), niobium (Nb), and oxygen (O) were distributed homogeneously across the nanocubes. Only K, Nb, and O were detected in the EDX spectrum of the KNbO3 powders obtained. Thus, KNbO3 nanocubes were successfully prepared using a solvothermal method at low temperature. (C)2013 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2013年08月, ［査読有り］

Structural study of heat-treated BaTiO3-KNbO3 nanocomposites with heteroepitaxial interface by synchrotron radiation powder diffraction
Eisuke Magome; Yoshihiro Kuroiwa; Chikako Moriyoshi; Ichiro Fujii; Kouichi Nakashima; Nobuhiro Kumada; Satoshi Wada, KNbO3 (KN)/BaTiO3 (BT) nanocomposite ceramics, in which a BT nanoparticle is thinly coated with KN crystals through the heteroepitaxial interface, are heat-treated at 1000 degrees C for 10 h, and the crystal structures are investigated by synchrotron radiation powder diffraction. The Rietveld analysis based on the multicomponent models reveals that the volumes of gradually distorted tetragonal components of BT are significantly decreased and the BT-KN solid solutions emerge in the nanocomposites by the heat-treatment. The suppression of the piezoelectric response in the heat-treated nanocomposites compared with the as-synthesized ones is attributed to these changes in the crystal structure. The core/multishell structure model for the ceramic grain is proposed, and the changes in the crystal structure are revealed to be caused at the heteroepitaxial interface regain between BT and KN. (C) 2013 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2013年08月, ［査読有り］

Effect of sintering condition and V-doping on the piezoelectric properties of BaTiO3-Bi(Mg1/2Ti1/2)O-3-BiFeO3 ceramics
Ichiro Fujii; Ryuta Mitsui; Kouichi Nakashima; Nobuhiro Kumada; Hisato Yabuta; Mikio Shimada; Takayuki Watanabe; Kaoru Miura; Satoshi Wada, 0.3BaTiO(3)-0.1Bi(Mg1/2Ti1/2)O-3-0.6BiFeO(3) ceramics were either doped with vanadium or sintered in calcined powder with the same composition. Compared to an undoped ceramic sintered without the calcined powder, both ceramics showed reduced leakage current densities (lower than 1 x 10(-7) A/cm(2)) and absence of dielectric relaxation behaviors observed in frequency- and temperature-dependent dielectric measurements. The Curie temperatures of both samples were higher than 460 degrees C. The maximum field-induced strain over the applied field, S-max/E-max, of 366 pm/V for the undoped ceramic sintered without the calcined powder increased to 455 and 799 pm/V for the V-doped sample and the sample sintered with the calcined powder, respectively. The increase was discussed with reduced concentrations of bismuth vacancy-oxygen vacancy defect dipoles. (C) 2013 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2013年08月, ［査読有り］

Low-temperature synthesis of SrZrO3 nanocubes by the composite-hydroxide-mediated approach
Kouichi Nakashima; Ichiro Fujii; Satoshi Wada, Strontium zirconate (SrZrO3) nanocubes were successfully synthesized by a composite-hydroxide-mediated (CHM) approach at low temperature using zirconium dioxide (ZrO2) and strontium hydroxide (Sr(OH)(2)) as raw materials. The effect of the atomic ratio of Sr/Zr in the raw materials was investigated. Subsequently, an acetic acid treatment of the product was performed. The X-ray diffraction (XRD) measurement confirmed perovskite SrZrO3 particles. Through scanning electron microscopy (SEM) observation, it was found that SrZrO3 nanocubes formed. These nanocubes tend to disperse as the atomic ratio of Sr/Zr in the raw material increased. Scanning transmission electron microscopy (STEM) revealed that the SrZrO3 nanocrystals had cube shape with sharp-edged corners when the Sr/Zr atomic ratio was 2/1. Observation via scanning transmission electron microscopy-energy dispersive X-ray (STEM-EDX) showed that Sr, Zr, and O were homogeneously distributed across the nanocubes. These results confirmed that the nanocubes were composed of SrZrO3. In the formation process, the rapid nuclei of SrZrO3 formed at around 230 degrees C, and crystals of SrZrO3 nanocubes grew. (C) 2013 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE BV
JOURNAL OF CRYSTAL GROWTH, 2013年08月, ［査読有り］

A new approach for the preparation of SrTiO3 nanocubes
Kouichi Nakashima; Masatoshi Kera; Ichiro Fujii; Satoshi Wada, This paper describes the preparation of SrTiO3 nanocubes with an average length of ∼20 nm. SrTiO3 nanoparticles were prepared using a solvothermal reaction at 240 °C for 18 h with [ (CH3) 2CHO]4Ti as a raw material and a little distilled water addition. X-ray diffraction measurements confirmed the presence of perovskite SrTiO3 particles. The water served as an oxygen source for producing the perovskite structure. Furthermore, a new approach to nanocube formation using a mixture of raw materials as titanium sources was investigated. Dispersed SrTiO3 nanocubes were successfully prepared using this approach and a solvothermal reaction performed at 260 °C for 18 h. SrTiO3 was synthesized from a mixture that included [ (CH3)2CHO] 4Ti and TiO2 as titanium sources. The [ (CH 3)2CHO]4Ti and TiO2 contributed to rapid nucleation and crystal growth, respectively. Scanning electron microscopy observations revealed that the particles were nanocubes approximately 20 nm in size.
Ceramics International, 2013年04月, ［査読有り］

Solvothermal preparation of potassium niobate/barium titanate nanocomplex ceramics with three dimensional network-configuration of structure-gradient region and their dielectric properties
Shintaro Ueno; Hideto Kawashima; Kouichi Nakashima; Nobuhiro Kumada; Eisuke Magome; Chikako Moriyoshi; Yoshihiro Kuroiwa; Yoshinori Fujikawa; Daisuke Tanaka; Masahito Furukawa; Satoshi Wada, To improve dielectric properties of barium titanate (BaTiO3, BT)-based ceramics, the BT/potassium niobate (KNbO3, KN) nanocomplex ceramics were designed to expect the formation of a three dimensional network-configuration of a structure-gradient region (SGR), where the polar vector can easily rotate. The KN epitaxial nanolayers were formed on BT compacts with a necking structure by a solvothermal method and the maximal dielectric constant of 1450 and the relatively large apparent piezoelectric constant d(33)* of 318 pm/V were recorded for the KN/BT nanocomplex ceramics. The experimental facts suggest that the configuration of the SGR, in addition to the relative density, is one of the important factors to enhance the dielectric properties of the KN/BT nanocomplex ceramics. (C) 2013 AIP Publishing LLC., AMER INST PHYSICS
Journal of Applied Physics, 2013年, ［査読有り］

Synthesis of SrTiO3 ceramics with necking structure coated with BaTiO3　　　　　　　　　　　　　　　
Kouichi Nakashima; Shogo Iwatsuki; Ichiro Fujii; Satoshi Wada
Transactions of the Materials Research Society of Japan, 2013年, ［査読有り］

The dielectric and piezoelectric properties of KNbO3/BaTiO3 composites with a wide BaTiO3 size distribution
Ichiro Fujii; Kenta Yamashita; Kouichi Nakashima; Nobuhiro Kumada; Eisuke Magome; Chikako Moriyoshi; Yoshihiro Kuroiwa; Satoshi Wada, KNbO₃ (KN) / BaTiO₃ (BT) composites with heteroepitaxial interfaces were solvothermally synthesized using the barium titanate powder with a wide particle size distribution. Compared with the composites prepared with a narrow particle size distributions, the relative density increased to 68 - 80 %. The dielectric constant was increased to 300 - 450, while an obvious increase in the electric-field-induced strain was not observed. The dielectric and piezoelectric properties were maximized at the KNbO₃ / BaTiO₃ molar ratio of 0.5., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2013年, ［査読有り］

Preparation of bismuth-based perovskites with non-integer A and B site valence and their properties
Ichiro Fujii; Atsushi Shimamura; Kouichi Nakashima; Nobuhiro Kumada; Hiroshi Funakubo; Yoshihiro Kuroiwa; Satoshi Wada, Non-integer A and B site cation valence perovskite oxides with bismuth and niobium cations were synthesized. Using the tolerance factor, some single phase perovskite oxides were obtained. For the A^1+xB^5-xO₃ type (Bi_x/2K_-x/2+1)(Ti_xNb_1-x)O₃ ceramics, the Curie temperature increased from approximately 200 to 350 °C with increasing x from 0.5 to 0.9. These results were discussed with the Abrahams relations., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2013年, ［査読有り］

Synthesis of BaZrO3 nanocrystals by wet chemical reaction
Kouichi Nakashima; Ichiro Fujii; Satoshi Wada, Low-temperature synthesis of barium zirconate (BaZrO₃) was carried out using the composite-hydroxide-mediated (CHM) approach. The CHM method is based on chemical reaction of materials in the eutectic hydroxide melt. In this system, the eutectic point is at an NaOH:KOH molar ratio of 51.5:48.5 and a temperature of 165°C. The raw materials used to prepare BaZrO₃ were zirconium dioxide and barium hydroxide. In this study, the morphology of the obtained BaZrO₃ powder was investigated. X-ray diffraction measurements confirmed the formation of BaZrO₃ with a perovskite structure. Scanning electron microscopy and transmission electron microscopy observations indicated that BaZrO₃ nanocrystals were formed., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2013年, ［査読有り］

Fabrication of textured BaTiO3 ceramics by electrophoretic deposition in a high magnetic field using single-domain particles
Ichiro Fujii; Tatsuya Kita; Kouichi Nakashima; Takahiro Takei; Nobuhiro Kumada; Tohru S. Suzuki; Tetsuo Uchikoshi; Yoshio Sakka; Yasunari Miwa; Shinichiro Kawada; Masahiko Kimura; Yoshihiro Kuroiwa; Satoshi Wada, BaTiO₃ (BT) ceramics were prepared by electrophoretic deposition (EPD) or slip casting (SC) in a high magnetic field (HM) of 12 T using single-domain or multi-domain BT particles. The {110}-oriented BT ceramics with a Lotgering factor of 25% were prepared by HM-EPD of the single-domain BT particles, while no texture was observed for the BT ceramics prepared by HM-SC of the single-domain BT particles and for the BT ceramics prepared using the multi-domain BT particles regardless of the preparation methods. These results were discussed with factors that reduced the magnetic anisotropy of the BT particles., The Materials Research Society of Japan
Transactions of the Materials Research Society of Japan, 2013年, ［査読有り］

Enhancement in the piezoelectric properties of BaTiO3-Bi(Mg1/2Ti1/2)O-3-BiFeO3 system ceramics by nanodomain
Ryuta Mitsui; Ichiro Fujii; Kouichi Nakashima; Nobuhiro Kumada; Yoshihiro Kuroiwa; Satoshi Wada, Barium titanate (BaTiO3, BT)-bismuth titanate magnesium oxide (Bi(Mg1/2Ti1/2)O-3, BMT)-bismuth ferrite (BiFeO3, BF) solid solution ceramics were prepared using a conventional solid-state synthesis, and their piezoelectric properties and microstructure were investigated. X-ray diffraction (XRD) patterns revealed the single phase of perovskite oxide for 0.3BT-0.1BMT-0.6BF ceramics. Strain electric field curves of the sample with 0.3BT-0.1BMT-0.6BF exhibit ferroelectric butterfly-like curves. A strain maximum/electric field maximum (S-max/E-max) was 330 pm/V. Transmission electron microscopy revealed dot-like domains(Nanodomains) inside the ferroelectric domain structures in the 0.3BT-0.1BMT-0.6BF. (C) 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved., ELSEVIER SCI LTD
CERAMICS INTERNATIONAL, 2013年, ［査読有り］

Crystal structure of BaTiO3-KNbO3 nanocomposite ceramics: relationship between dielectric property and structure of heteroepitaxial interface
Eisuke Magome; Yoshihiro Kuroiwa; Hironori Yoshimura; Chikako Moriyoshi; Kenta Yamashita; Ichiro Fujii; Kouichi Nakashima; Nobuhiro Kumada; Satoshi Wada, High-energy synchrotron radiation powder diffraction experiments have been carried out to investigate the crystal structure of solvothermally synthesized KNbO3 (KN)/BaTiO3 (BT) nanocomposite ceramics in which a ceramic grain consists of a BT nanoparticle thinly coated with KN crystals through the heteroepitaxial interface. Rietveld analysis reveals that the ceramic grain has the core/multishell structure consisting of a BT core and distorted BT and KN multishells. BT is gradually distorted in the large region to form the interface with KN from the tetragonal structure at the core toward the cubic structure at the boundary between BT and KN. The variations of the volume of the distorted interface region of BT and the dielectric property of the ceramics show similar trends to the variation of KN/BT molar ratio, which suggests that the electrically soft interface of BT nanoparticles governs the dielectric properties of the ceramics. (c) 2012 The Japan Society of Applied Physics, IOP PUBLISHING LTD
Japanese Journal of Applied Physics, 2012年, ［査読有り］

Nanostructure control of barium titanate-potassium niobate nanocomplex ceramics and their enhanced ferroelectric properties
Satoshi Wada; Kenta Yamashita; Ichiro Fujii; Kouichi Nakashima; Nobuhiro Kumada; Chikako Moriyoshi; Yoshihiro Kuroiwa; Yoshinori Fujikawa; Daisuke Tanaka; Masahito Furukawa, Barium titanate (BaTiO3, BT)-potassium niobate (KNbO3, KN) nanocomplex ceramics with various KN/BT molar ratios were prepared by a solvothermal method. From a transmission electron microscopy (TEM) observation, it was confirmed that the KN layer thickness on BT particles was controlled from 5 to 40 nm by controlling KN/BT molar ratios. Their dielectric constants were measured at room temperature and 1 MHz, and the maximum dielectric constant of 370 was measured for the BT-KN nanocomplex ceramics with a KN thickness of 22 nm. TEM observation revealed that at a KN thickness below 22 nm, the BT/KN heteroepitaxial interface was assigned as a strained interface, while at 40 nm, the interface was assigned as a relaxed one. These results suggested that the strained heteroepitaxial interface could be responsible for the enhanced dielectric properties. (C) 2012 The Japan Society of Applied Physics, JAPAN SOC APPLIED PHYSICS
Japanese Journal of Applied Physics, 2012年, ［査読有り］

Low-temperature synthesis and formation mechanism of BaZrO3 cubes by composite-hydroxide-mediated approach　　　　　　　　　　　　　　　
Kouichi Nakashima; Ichiro Fujii; Satoshi Wada
Journal of the Society of Inorganic Materials, Japan, 2012年, ［査読有り］

Structural, dielectric, and piezoelectric properties of BaTiO3-Bi(Ni1/2Ti1/2)O-3 ceramics
Ichiro Fujii; Kouichi Nakashima; Nobuhiro Kumada; Satoshi Wada, Undoped and Mn-doped (1-x)BaTiO3-xBi(Ni1/2Ti1/2)O-3 (x = 0.03-0.7) ceramics were synthesized by a conventional solid state route. X-ray diffraction patterns revealed that the crystal structure was a tetragonal perovskite at x = 0.03, a pseudo-cubic perovskite at x = 0.1 and 0.3, and mixed phases at x = 0.5-0.7. The dielectric and piezoelectric responses were ferroelectric at x = 0.03 and relaxor-like at x = 0.1-0.7. The polarization electric field and strain electric field responses were suppressed at the relaxor compositions, and the large-field piezoelectric constant was 25-40 pm/V at x = 0.3-0.7. As x increased, the temperature of the maximum dielectric constant decreased compared to the Curie temperature of BaTiO3 at x <= 0.1, and then it increased and reached 325 degrees C at x = 0.7. At x = 0.3-0.7, the dielectric constant was less temperature dependent. These results suggest that the samples may be suitable for high temperature capacitor application. (C)2012 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2012年01月, ［査読有り］

DFT studies of ESR parameters for N-O centered radicals, N-alkoxyaminyl and aminoxyl radicals
Akio Tanaka; Kouichi Nakashima, Theoretical calculations of ESR parameters for aminoxyl radicals have been widely studied using the density functional theory (DFT) calculations. However, the isomer N-alkoxyaminyl radicals have been limitedly studied. With the use of experimental data for 46 N-alkoxyaminyl and 38 aminoxyl radicals, the isotropic N-14 hyperfine coupling constants (a(N)) and g-factors have been theoretically estimated by several DFT calculations. The best calculation scheme of a(N) for N-alkoxyaminyl radicals was PCM/B3LYP/6-31++G(d, p) (R-2 = 0.9519, MAE = 0.034 mT), and that for aminoxyl radicals was PCM/BHandHLYP/6-31++ G(3df, 3pd) (R-2 = 0.9336, MAE = 0.057 mT). For aminoxyl radicals, the solvation models in calculations enhanced the accuracy of reproducibility. In contrast, for N-alkoxyaminyl radicals the calculations with solvation models provided no improvement. The differences in the best functionals between two types of radicals were thought to come from the contribution ratios of neutral and dipolar canonical structures in resonance forms. The a(N) for N-alkoxyaminyl radicals that were stabilized by small contribution of dipolar canonical structures could be precisely reproduced by B3LYP with only 20% HF exact exchange. In contrast, the a(N) for aminoxyl radicals stabilized by large contribution of dipolar canonical structures was well reproduced by BHandHLYP with 50% HF exchange. The best calculation scheme of g-factors was IEFPCM/B3LYP/6-31+G(d, p) (R-2 = 0.9767, MAE = 0.0001) for not only aminoxyl but also N-alkoxyaminyl radicals. Copyright (C) 2011 John Wiley & Sons, Ltd., WILEY-BLACKWELL
MAGNETIC RESONANCE IN CHEMISTRY, 2011年09月, ［査読有り］

Structural, Dielectric, and Piezoelectric Properties of Mn-Doped BaTiO3-Bi(Mg1/2Ti1/2)O-3-BiFeO3 Ceramics
Ichiro Fujii; Ryuta Mitsui; Kouichi Nakashima; Nobuhiro Kumada; Mikio Shimada; Takayuki Watanabe; Jumpei Hayashi; Hisato Yabuta; Makoto Kubota; Tetsuro Fukui; Satoshi Wada, Mn-doped (0.9 - x) BaTiO3-0.1Bi(Mg1/2Ti1/2)O-3-xBiFeO(3) (x = 0.6, 0.7, and 0.8) ceramics were studied as candidate lead-free piezoelectric materials. The crystal structures were a pseudo-cubic perovskite at x = 0.6, a rhombohedral perovskite at x = 0.8, and a mixture of the pseudocubic and rhombohedral perovskite at x = 0.7. The Curie temperature was found to be 470 degrees C at x = 0.6 and more than 600 degrees C at x = 0.7 and 0.8. A strong pinning of domain walls was observed for high-field responses at x = 0.7 and 0.8, which was relaxed by high-temperature annealing and subsequent quenching. Piezoelectric properties increased with decreasing x, and the small-field piezoelectric constants d(33) and d(31) were 94 and 31 pC/N at x = 0.6, respectively. (C) 2011 The Japan Society of Applied Physics, JAPAN SOC APPLIED PHYSICS
JAPANESE JOURNAL OF APPLIED PHYSICS, 2011年09月, ［査読有り］

Preparation of BaZrO3 cubes by composite-hydroxide-mediated approach at low temperature
Kouichi Nakashima; Ichiro Fujii; Satoshi Wada, Barium zirconate (BaZrO3) was prepared by a low-temperature composite-hydroxide-mediated (CHM) approach. The synthesis was performed using zirconium dioxide (ZrO2) and barium hydroxide (Ba(OH)(2)) as starting materials and a mixture of anhydrous hydroxides with NaOH and KOH as the reaction medium at 170-230 degrees C for 18 h. Measurement by X-ray diffraction (XRD) confirmed the presence of perovskite BaZrO3 particles and indicated that the lattice of the obtained BaZrO3 was cubic. The amount of BaZrO3 increased as the reaction temperature increased. Scanning electron microscopy (SEM) observation revealed that the BaZrO3 particles were cube shaped, with side lengths of 50-240 nm and sharp-edged corners. It was found that small-scale BaZrO3 cubes could be shaped from ZrO2 and Ba(OH)(2). (C) 2011 The Ceramic Society of Japan. All rights reserved., CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN, 2011年06月, ［査読有り］

DFT studies of N-alkoxyaminyl radicals: ESR parameters, UV-vis absorptions and generations
Akio Tanaka; Kouichi Nakashima; Yozo Miura, Although aminoxyl radicals.(RR/NO) are well-known as organic stable free radicals, the isomeric radicals. N-alkoxyaminyl radicals (RNOR/), are scarcely studied in the area of theoretical study. We carried out the theoretical calculation of the isotropic (14)N hyperfine coupling constants (a(N)), g-factors, electronic absorbances, and generation mechanisms of N-alkoxyaminyl radicals. For thirty one N-alkoxyaminyl radicals, the PCM-DFF calculation at B3LYP/6-31+G(d,p) could well reproduce the experimental data of a(N) and g-factors, where R(2) were 0.9796 and 0.9439, respectively. The UV-vis spectra were moderately reproduced by PCM-TD-DFT (PBE0/6-31+G(d,p)), where R(2) was 0.9205. Additionally, the use of a linear scaling procedure precisely reproduced the UV-vis spectrum. The activation Gibbs free energies for the generation of N-alkoxyaminyl radicals and aminoxyl radicals in the competing reactions of nitroso compounds with alkyl radicals were estimated by DFT and coupled cluster calculations. The activation free energies for the generation of N-alkoxyaminyl radicals were estimated to be 9-18 kcal/mol at B3LYP/6-31+G(d,p). The reported product ratios in the competing reactions could be reasonably explained by the differences in the activation free energies. (C) 2011 Elsevier Ltd. All rights reserved., PERGAMON-ELSEVIER SCIENCE LTD
TETRAHEDRON, 2011年03月, ［査読有り］

Preparation of BaZrO(3) nanoparticles using a solvothermal reaction
Kouichi Nakashima; Takayuki Goto; Shougo Iwatsuki; Masatoshi Kera; Ichiro Fujii; Satoshi Wada, Barium zirconate (BaZrO(3)) nanoparticles were successfully prepared by a solvothermal reaction. These were synthesized by a solvothermal method at 230 degrees C-240 degrees C for 18 h using a mixture solution of ethanol and 2-metoxy-thanol as the reaction medium. The prepared particles were collected using a centrifugal separator. The X-ray diffraction (XRD) measurement confirmed the presence of perovskite BaZrO(3) particles. The scanning electron microscopy (SEM) observations revealed that the particles were composed of highly dispersed nanoparticles. The results of our study indicate that the addition of water to the reaction medium is an important for the preparation of a perovskite structure and control of the size of the BaZrO(3)., IOP PUBLISHING LTD
3RD INTERNATIONAL CONGRESS ON CERAMICS (ICC3): ADVANCES IN ELECTRO CERAMICS, 2011年, ［査読有り］

Enhanced piezoelectric response of BaTiO3-KNbO3 composites
Ichiro Fujii; Shigehito Shimizu; Kenta Yamashita; Kouichi Nakashima; Nobuhiro Kumada; Chikako Moriyoshi; Yoshihiro Kuroiwa; Yoshinori Fujikawa; Daisuke Tanaka; Masahito Furukawa; Satoshi Wada, The piezoelectric response of solvothermally synthesized BaTiO3 (BT)-KNbO3 (KN) composites (the nominal BT/KN ratio was 1) with distinct interfaces was investigated. The x-ray diffraction pattern showed two distinct peaks began to merge into a singular broad peak at a two-theta position between (200) and (002) tetragonal-related peaks of BT. The transmission electron microscopy observation showed a heteroepitaxial interface region between BT single-crystal particles and deposited KN crystals. The large-field piezoelectric constant was 136 pC/N, which was three times larger than that of a sintered 0.5BT-0.5KN composite. The enhanced piezoelectric response was attributed to the strained epitaxial interface region. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3662397], AMER INST PHYSICS
Applied Physics Letters, 2011年, ［査読有り］

Preparation of barium titanate-potassium niobate nano-structured ceramics with artificial MPB structure by solvothermal method
Satoshi Wada; Shigehito Shimizu; Kenta Yamashita; Ichiro Fujii; Kouichi Nakashima; Nobuhiro Kumada; Yoshihiro Kuroiwa; Yoshinori Fujikawa; Daisuke Tanaka; Masahito Furukawa, Barium titanate (BaTiO3, BT)-potassium niobate (KNbO3, KN) (BT-KN) nanostructured ceramics with a distorted interface region, i.e., artificial morphotropic phase boundary (MPB) structure, were prepared by the solvothermal method. The results of the optimization of reaction conditions showed that the metastable region of only KN crystal growth was obtained using a mixture of KOH and K2CO3 as the K source and Nb2O5 as the Nb source in ethanol. Moreover, KN formation under the metastable region using a particle compact composed of a mixture of BT and Nb2O5 particles as substrates resulted in the successful preparation of BT-KN nanostructured ceramics with an artificial MPB region and a porosity of around 35%. This is the first report on the preparation of ceramics with a heteroepitaxial interface between BT and KN below 230 degrees C. (C) 2011 The Japan Society of Applied Physics, IOP PUBLISHING LTD
Japanease Journal of Applied Physics, 2011年, ［査読有り］

Synthesis of Y2O3:Eu phosphor with various particles morphologies by solvothermal reaction in methanol-water system
Kouichi Nakashima; Midori Saito; Valery Petrykin; Shu Yin; Tsugio Sato; Masato Kakihana, A methanol–water mixed solvent was used as a reaction medium for the synthesis of Eu³⁺-doped Y₂O₃ (Y₂O₃:Eu) phosphor. Y₂O₃:Eu was prepared under solvothermal conditions at 150–300°C for 3–24 h using a solution of water and methanol as the reaction medium followed by heat treatment at 1000°C for 2 h. The phase composition and optical properties of the products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence spectroscopy. The powders obtained were composed of plate-like particles, spindle-like particles, and whisker particles and were different for samples prepared under supercritical, subcritical, and normal conditions of methanol. With the reaction temperature increasing, the particle size became smaller, in particular, the particles were ∼500 nm in size at 300°C under supercritical condition of methanol. After calcination at 1000°C for 2 h, the obtained powders retained the initial shape. The emission peaks of the fluorescence were assigned to the f–f transitions of the Eu³⁺ and exhibited red emission. The fluorescence intensities and internal quantum efficiency exhibited various values dependence on the morphology of the obtained particles., 公益社団法人 日本セラミックス協会
Journal of the Ceramic Society of Japan, 2011年, ［査読有り］

Microwave-assisted synthesis of (tris-acetylacetonato)(2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline)terbium(Ⅲ) complex with outstanding high green luminescence
Kouichi Nakashima; Yoshitaka Masuda; Takeko Matsumura-Inoue; Masato Kakihana, Microwave-assisted synthesis method enabled the preparation of the (tris-acetylacetonate)(2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolinate) terbium(III) (Tb(acac)(3)(dmdpphen)) complex with outstanding high green luminescence. This method is appropriate for green chemistry and energy-saving processes. The Tb(acac)(3)(dmdpphen) complex has good thermal stability. Emission peaks are assigned to the f-f transitions of the Tb(3+). The Tb(acac)(3)(dmdpphen) complex is expected to be used in functional materials of electronic products. (C) 2008 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE BV
Journal of Luminescence, 2009年03月, ［査読有り］

Bis(2, 3, 5-triphenyltetrazolium)Tetrathiocyanatocovaltate(Ⅱ)
Kouichi Nakashima; Naoyuki Kawame; Yoshiko Kawamura; Osamu Tamada; Jun Yamauchi, The title compound, (C(19)H(15)N(4))(2)[Co(NCS)(4)], has two crystallographycally different molecules of bis(2,3,5-triphenyltetrazolium) tetrathiocyanatecobaltate in the asymmetric unit. There are only minor geometric differences between them. Each cobalt(II) ion is coordinated by the N atoms of four NCS anions, showing the magnitude of the magnetic moment expected from the NCS(-) crystal field strength., WILEY-BLACKWELL
Acta Crystallographica E, 2009年, ［査読有り］

Methanol-water system for solvothermal synthesis of YVO4:Eu with high photoluminescent intensity
Sulawan Kaowphong; Kouichi Nakashima; Valery Petrykin; Somchai Thongtem; Masato Kakihana, A methanol-water mixed solvent was used as a reaction medium for the preparation of Eu3+-doped YVO4 phosphor materials. These were synthesized by a solvothermal method at 150 degrees-300 degrees C using a 10 vol% solution of water in methanol as the reaction medium followed by calcination at 1000 degrees-1200 degrees C. The phase composition and optical properties of the products were characterized by X-ray diffraction, scanning electron microscope, and photoluminescence spectroscopy. The powders obtained were composed of spherical particles similar to 0.5 mu m in size, with an internal structure that was different for samples prepared under subcritical and supercritical conditions of methanol. After the calcination, the powders obtained at 240 degrees-300 degrees C retained the initial raspberry-like morphology, whereas the morphology of samples prepared at 150 degrees-210 degrees C changed significantly due to noticeable sintering. The fluorescence intensity exhibited by the prepared samples was higher than the fluorescence intensity shown by one of the best commercial YVO4:Eu phosphors having a large particle size., WILEY-BLACKWELL
Journal of the American Ceramic Society, 2009年, ［査読有り］

Characterization of X-ray-irradiated β-Ca3(PO4)2:Dy by means of ESR spectroscopy
Kouichi Nakashima; Masato Kakihana; Jun Yamauchi, Electron spin resonance (ESR) spectra caused by a stable trapped H atom, a Dy(3+)ion, and a PO4 unit were observed in X-ray-irradiated dysprosium-doped beta-tricalcium phosphate (beta-Ca-3(PO4)(2):Dy, beta-TCP:Dy) phosphor. The ESR spectrum of the H atom in the X-ray-irradiated beta-TCP:Dy phosphor was slightly different from that of nondoped X-ray-irradiated beta-TCP, suggesting that the Dy3+ spin state has a significant effect on the relaxation time of electron spins. The electron spin echo of the H atom was observed in the X-ray-irradiated beta-TCP but not in the corresponding X-ray-irradiated beta-TCP:Dy phosphor., SPRINGER WIEN
Applied Magnetic Resonance, 2008年03月, ［査読有り］

Dynamical effect study of a stable trapped hydrogen atom by ESR spectroscopy
Kouichi Nakashima; Jun Yamauchi, Effective spin Hamiltonian parameters of a stable trapped hydrogen atom (H atom) in X-ray-irradiated P-tricalcium phosphate (beta-Ca-3(PO4)(2), beta-TCP) were estimated by high frequency ESR (Q-band). The dynamical effect of the H atom was investigated at various temperatures by CW-ESR (X-band) spectroscopy., CHEMICAL SOC JAPAN
CHEMISTRY LETTERS, 2006年07月, ［査読有り］

Magnetic properties of gadolinium-doped β-tricalcium phosphate
Kouichi Nakashima; Jun Yamauchi, The frequency of radiant energy used in the majority of electron spin resonance (ESR) spectrometers is approximately 9 GHz (X-band), in the medium-frequency microwave region. Recently, high frequency microwave (Q-band) has been used to measure ESR spectra because high frequency ESR enhances the sensitivity. In the present work, ESR spectra (X-band, Q-band) of gadolinium-doped beta-tricalcium phosphate (beta-Ca-3(PO4)(2):Gd, beta-TCP:Gd) were investigated. X-band and Q-band ESR spectra were recorded. Q-band ESR spectra was observed clearer than X-band ESR spectra. The ESR spectra were assigned to the typical fine structure of the Gd3+ ion. The crystal-field parameters obtained at room temperature were determined to be b(2)(0) = -267.0, b(4)(0) = -1.5, and b(6)(0) = -6.4 cm(-1). (c) 2005 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE SA
Journal of Alloys and Compounds, 2006年02月, ［査読有り］

ESR investigation of a stable trapped hydrogen atom in X-ray-irradiated β-tricalcium phosphate at room temperature
Kouichi Nakashima; Jun Yamauchi, AMER CHEMICAL SOC
Journal of the American Chemical Society, 2005年, ［査読有り］

Thermoluminescence mechanism of dysprosium-doped β-tricalcium phosphate phosphor
Kouichi Nakashima; Michiko Takami; Masatoshi Ohta; Tamotsu Yasue; Jun Yamauchi, beta-Tricalcium phosphate (beta-Ca-3(PO4)(2), beta-TCP) and dysprosium-doped beta-tricalcium phosphate (beta-Ca-3(PO4)(2):Dy, beta-TCP:Dy) phosphor were synthesized. Powder X-ray diffraction, electron spin resonance (ESR), photoluminescence (PL), and thermoluminescence (TL) were measured. Although no PL and TL could be identified for undoped beta-TCP, PL and TL were observed for beta-TCP:Dy phosphor. The TL emission peaks are assigned to the f-f transitions of the Dy3+ ion which were found to be the same as those of the PL of beta-TCP:Dy phosphor. A detailed analysis of the TL peak shape can give information on the trap depth (activation energy epsilon), indicating the trap depth of epsilon = 1.1 eV from Hoogenstraaten's method. We succeeded in detecting the stable trapped hydrogen atom in the X-ray-irradiated beta-TCP:Dy phosphor at room temperature for several months using ESR. The TL phenomenon of beta-TCP:Dy phosphor is related with these trapped hydrogen atoms. (C) 2004 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE BV
Journal of Luminescence, 2005年01月, ［査読有り］

The relationship between thermoluminescence and electron spin resonance of dysprosium-doped β-tricalcium phosphate phosphor　　　　　　　　　　　　　　　
Kouichi Nakashima; Michiko Takami; Masatoshi Ohta; Yoshio Iima; Jun Yamauchi
Advances in ESR Applications, 2003年, ［査読有り］

Hydrothermal synthesis of β- tricalcium phosphate from amorphous calcium phosphate
Takeshi Toyama; Kouichi Nakashima; Tamotsu Yasue, β-tricalcium phosphate (β-TCP) is usually prepared by burning a mixture of dicalcium hydrogenphosphate anhydride (DCPA) and calcium carbonate (CaCO3) above 1100°C. However, hydrothermal synthesis may be a more effective process for energy-saving. In addition, amorphous calcium phosphate (ACP) is very useful as a raw material for the morphological control of crystalline calcium phosphates. The present work investigated about the hydrothermal synthesis of β-TCP from ACP. ACP (Ca/P atomic ratio of 1.25-1.55) as starting material was obtained by a hydrolysis reaction of a calcium dihydrogenphosphate monohydrate (MCP) solution. Hydrothermal synthesis of β-TCP occurred under the following conditions: liquid/solid weight ratio, 30
carboxylic acid (formic acid, acetic acid, propionic acid, butyric acid and valeric acid) concentration, 0-1.5 mol · dm-3
temperature, 160-260°C
time, 0-72 h. ACP crystallized into DCPA in hydrothermal conditions at 160°C, and was transformed into two phases, β-TCP and DCPA, above 200°C. Single-phase β-TCP formed at 220°C. Hydrothermal synthesis of β-TCP occurred under the following optimum conditions: formic acid solution, 1.0 mol · dm-3
temperature, 220°C
time, 3 h. Ca/P atomic ratio of the hydrothermal synthesized β-TCP was 1.48±0.01 and the product was quantified as Ca2.98(HPO4)0.04(PO4)1.96 ., Ceramic Society of Japan
ournal of the Ceramic Society of Japan, 110, 716-721, 2002年, ［査読有り］

〔主要な業績〕（解説）チタン酸バリウムナノキューブの合成と表面再構成　　　　　　　　　　　　　　　
中島光一, 単著
Fine Ceramics Report, 日本ファインセラミックス協会, 2022年04月20日

〔主要な業績〕（解説）電子スピン共鳴を用いた機能性無機材料の解析　　　　　　　　　　　　　　　
中島光一, 単著
Journal of the Society of Inorganic Materials, Japan, 2021年11月01日, ［査読有り］

〔主要な業績〕エレクトロニクス用セラミックスの開発、評価方法と応用　　　　　　　　　　　　　　　
中島光一, 分担執筆
技術情報協会, 2020年08月
9784861047985

（解説）水素原子の電子スピン共鳴　　　　　　　　　　　　　　　
中島光一
Phosphorus Letter, 2008年

（解説）高輝度発光を有する水溶性金属錯体への挑戦　　　　　　　　　　　　　　　
中島光一; 垣花眞人
化学、化学同人, 2007年

水熱法を用いたハイドロキシアパタイトの合成　　　　　　　　　　　　　　　
○三澤咲乃、中島光一
日本分析化学会関東支部 第１６回茨城地区分析技術交流会, 2019年11月

水溶性チタン錯体水溶液を出発原料とするチタン酸ストロンチウムの水熱合成　　　　　　　　　　　　　　　
○廣中航太、山﨑玲奈、大河内尚弥、小林芳男、垣花眞人、中島光一
日本分析化学会関東支部 第１６回茨城地区分析技術交流会, 2019年11月

X線CT造影剤として利用可能なBi/SiO2ナノカプセルの液相合成　　　　　　　　　　　　　　　
〇山中竜志、小林芳男、垣花眞人、中島光一
日本分析化学会関東支部 第１６回茨城地区分析技術交流会, 2019年11月

水分解光触媒としての性能を有するSrTiO3の組成分析と微構造解析　　　　　　　　　　　　　　　
○山﨑玲奈、大河内尚弥、小林芳男、垣花眞人、阿部竜、中島光一
日本分析化学会関東支部 第１６回茨城地区分析技術交流会, 2019年11月

Development of a method for silica-coating luminescent materials　　　　　　　　　　　　　　　
○Mizuki Ito; Noriko Yamauchi; Kouichi Nakashima; Sakiko Sato; Hiroki Yoshizaki; Ryota Yamanashi; Hiroshi Okura; Yoshio Kobayashi
The 15th International Student Conference in Ibaraki, 2019年11月

Development of a technique for ZrO2-coating by sol-gel method　　　　　　　　　　　　　　　
○Akira Miwano; Noriko Yamauchi; Kouichi Nakashima; Yoshio Kobayashi
The 15th International Student Conference in Ibaraki, 2019年11月

Development of a technique for siloca-coating of metallic Zn nanoparticles　　　　　　　　　　　　　　　
Satoru Furukawa; Noriko Yamauchi; Kouichi Nakashima; Kenichi Watanabe; Hidekazu Koda; Hiroshi Kunigami; Hideki Kunigami; Yoshio Kobayashi
The 15th International Student Conference in Ibaraki, 2019年11月

Development of gold-immobilized magnetite nanoparticles and their imaging properties　　　　　　　　　　　　　　　
○Yukina Kobayashi; Noriko Yamauchi; Kouichi Nakashima; Tomoya Inose; Chihiro Kato; Masayuki Tokunaga; Kohsuke Gonda; Yoshio Kobayashi
The 15th International Student Conference in Ibaraki, 2019年11月

Detailed observation of Pt co-catalyst morphology and dispersion on SrTiO3 photocatalyst　　　　　　　　　　　　　　　
○Reina Yamazaki; Yoshio Kobayashi; Masato Kakihana; Masanobu Higashi; Ryu Abe; Kouichi Nakashima
The 13th Pacific Rim Conference of Ceramic Societies（PACRIM13）, 2019年10月

Electron microscopy of surface reconstruction of a SrTiO3 photocatalyst　　　　　　　　　　　　　　　
○Kouichi Nakashima; Reina Yamazaki; Naoya Okouchi; Yoshio Kobayashi; Masato Kakihana; Masanobu Higashi; Ryu Abe
The 13th Pacific Rim Conference of Ceramic Societies（PACRIM13）, 2019年10月

イットリウム固溶部分安定化ジルコニア（YTZ）の熱化学ヒーリング　　　　　　　　　　　　　　　
○三ツ井嘉隆、中島光一、阿部修実
第３５回日本セラミックス協会関東支部発表会, 2019年09月

チタン酸ストロンチウム水分解光触媒粒子の欠陥制御　　　　　　　　　　　　　　　
○大河内尚弥、山﨑玲奈、小林芳男、垣花眞人、東正信、阿部竜、中島光一
第３５回日本セラミックス協会関東支部発表会, 2019年09月

チタン酸バリウムのナノキューブ化に及ぼす出発原料の効果　　　　　　　　　　　　　　　
○小名木海飛、小林芳男、垣花眞人、中島光一
第３５回日本セラミックス協会関東支部発表会, 2019年09月

シングルナノサイズのビスマス金属の合成　　　　　　　　　　　　　　　
○赤松駿介、山中竜志、小林芳男、垣花眞人、中島光一
第３５回日本セラミックス協会関東支部発表会, 2019年09月

液相プロセスによるジルコニアコーティング技術の開発　　　　　　　　　　　　　　　
○三輪野祥、米澤岳洋、山内紀子、中島光一、小林芳男
化学工学会横浜大会, 2019年08月

がんの画像診断を目的としたインドシアニングリーン含有ポリ乳酸-グリコール酸共重合体ナノ粒子の開発　　　　　　　　　　　　　　　
○田山真由、山内紀子、中島光一、猪瀬智也、徳永正之、加藤智尋、 権田幸祐、小林芳男
化学工学会横浜大会, 2019年08月

Ni/SiO2ナノ粒子の作製法の開発　　　　　　　　　　　　　　　
○田子愛理、山内紀子、中島光一、小林芳男
化学工学会横浜大会, 2019年08月

量子ビームを用いたSrTiO3光触媒ナノクリスタルの構造解析　　　　　　　　　　　　　　　
中島光一
平成３０年度文部科学省ナノテクノロジープラットフォーム事業,京大・ＪＡＥＡ・ＱＳＴ微細構造解析プラットフォーム地域セミナー,電顕・放射光による反応・構造解析, 2019年02月, ［招待有り］

SrTiO3水分解光触媒活性に及ぼすPt助触媒の効果　　　　　　　　　　　　　　　
山﨑玲奈、東正信、阿部竜、垣花眞人、中島光一
第５７回セラミックス基礎科学討論会, 2019年01月

Ｘ線ＣＴ造影機能を有するBi/SiO2ナノカプセルの開発　　　　　　　　　　　　　　　
山中竜志、徳増旭俊、猪瀬智也、徳永正之、鳩山恵一朗、垣花眞人、権田幸祐、小林芳男、中島光一
第５７回セラミックス基礎科学討論会, 2019年01月

Development of Au-immobilized quantum dots/silica core-sgell nanoparticles for multimodal imaging　　　　　　　　　　　　　　　
Mayu Tayama; Kouichi Nakashima; Keiichiro Hatoyama; Masayuki Tokunaga; Takashi Kamei; Kohsuke Gonda; Yoshio Kobayashi
茨城大学学生国際会議, 2018年12月

医療用画像診断用Au担持量子ドット/シリカコア－シェル型ナノ粒子の作製法の開発　　　　　　　　　　　　　　　
田山真由、中島光一、鳩山恵一朗、徳永正之、権田幸祐、小林芳男
第２９回 日本化学会 関東支部 茨城地区 研究交流会, 2018年11月

チタン酸バリウムナノ粒子の水熱合成　　　　　　　　　　　　　　　
小名木海飛、垣花眞人、中島光一
第２９回 日本化学会 関東支部 茨城地区 研究交流会, 2018年11月

チタン酸ストロンチウムナノ粒子の合成　　　　　　　　　　　　　　　
大河内尚弥、山﨑玲奈、垣花眞人、中島光一
第２９回 日本化学会 関東支部 茨城地区 研究交流会, 2018年11月

ビスマス金属ナノ粒子の形態制御　　　　　　　　　　　　　　　
赤松駿介、山中竜志、徳増旭俊、垣花眞人、権田幸祐、小林芳男、中島光一
第２９回 日本化学会 関東支部 茨城地区 研究交流会, 2018年11月

がんマルチモーダルイメージング用金担持量子ドット/シリカコア－シェル型ナノ粒子の合成法の開発　　　　　　　　　　　　　　　
田山真由、中島光一、鳩山恵一朗、徳永正之、権田幸祐、小林芳男
化学工学会 第５０回秋季大会, 2018年09月

コア－シェル型Cu/SiO2粒子の作製法の開発　　　　　　　　　　　　　　　
林田光、中島光一、小林芳男
化学工学会 第５０回秋季大会, 2018年09月

シリカカプセル化金ナノロッド複合ナノ粒子の開発とそのＸ線ＣＴ造影能評価　　　　　　　　　　　　　　　
猪瀬智也、中島光一、及川隆洋、鳩山恵一朗、徳永正之、権田幸祐、小林芳男
化学工学会 第５０回秋季大会, 2018年09月

ニオブ酸ナトリウムのナノキューブ化に及ぼす出発原料の効果　　　　　　　　　　　　　　　
戸嶋康晴、小林芳男、垣花眞人、中島光一
日本セラミックス協会 第３１回秋季シンポジウム, 2018年09月

SrTiO3水分解光触媒粒子の微構造解析　　　　　　　　　　　　　　　
中島光一、山﨑玲奈、小林芳男、石垣徹、大山研司、米田安宏、石川喜久、関野徹、殷シュウ、垣花眞人、東正信、阿部竜
日本セラミックス協会 第３１回秋季シンポジウム, 2018年09月

Electron microscopy observation of SrTiO3 nanocrystals synthesized via hydrothermal method　　　　　　　　　　　　　　　
Kouichi Nakashima; Reina Yamazaki; Yoshio Kobayashi; Tohru Ishigaki; Kenji Ohoyama; Yasuhiro Yoneda; Yoshihisa Ishikawa; Tohru Sekino; ShuYin; Masato Kakihana; Masanobu Higashi; Ryu Abe
6th International Solvothermal and Hydrothermal Association Conference（ISHA2018）, 2018年08月

精密微粒子設計に基づくビスマス系Ｘ線ＣＴ造影剤の開発　　　　　　　　　　　　　　　
山中竜志、徳増旭俊、猪瀬智也、徳永正之、鳩山恵一朗、垣花眞人、権田幸祐、小林芳男、中島光一
粉体粉末冶金協会 平成３０年度春季大会（第１２１回講演大会）, 2018年05月

水分解光触媒の高活性化を目指したSrTiO3ナノクリスタルの合成　　　　　　　　　　　　　　　
中島光一、山﨑玲奈、小林芳男、石垣徹、大山研司、米田安宏、関野徹、殷シュウ、垣花眞人、東正信、阿部竜
粉体粉末冶金協会 平成３０年度春季大会（第１２１回講演大会）, 2018年05月

ビスマス金属ナノ粒子を用いたＸ線ＣＴ造影剤の開発　　　　　　　　　　　　　　　
山中竜志、徳増旭俊、猪瀬智也、徳永正之、鳩山恵一朗、垣花眞人、権田幸祐、小林芳男、中島光一
日本化学会 第９８回年会, 2018年03月

溶液反応化学に立脚したSrTiO3ナノクリスタルの合成　　　　　　　　　　　　　　　
山﨑玲奈、小林芳男、石垣徹、大山研司、米田安宏、関野徹、殷シュウ、垣花眞人、東正信、阿部竜、中島光一
日本化学会 第９８回年会, 2018年03月

Electron microscope investigations of nanocrystals　　　　　　　　　　　　　　　
第２回 茨城大学 量子線科学 国際シンポジウム, 2017年12月, ［招待有り］

水熱法を用いたチタン酸ストロンチウムナノ粒子の合成　　　　　　　　　　　　　　　
山﨑玲奈、小林芳男、石垣徹、大山研司、米田安宏、関野徹、殷シュウ、垣花眞人、東正信、阿部竜、中島光一
第２８回 日本化学会 関東支部 茨城地区 研究交流会, 2017年12月

ビスマス金属ナノ粒子の液相合成　　　　　　　　　　　　　　　
山中竜志、徳増旭俊、猪瀬智也、徳永正之、鳩山恵一朗、垣花眞人、権田幸祐、小林芳男、中島光一
第２８回 日本化学会 関東支部 茨城地区 研究交流会, 2017年12月

水熱法を用いたフッ化カルシウムの合成　　　　　　　　　　　　　　　
和氣諒太、小林芳男、垣花眞人、中島光一
第２８回 日本化学会 関東支部 茨城地区 研究交流会, 2017年12月

さまざまなニオブ原料を用いたNaNbO3ナノキューブ合成　　　　　　　　　　　　　　　
戸嶋康晴、小林芳男、垣花眞人、中島光一
第２８回 日本化学会 関東支部 茨城地区 研究交流会, 2017年12月

がんの画像診断および治療用金ナノロッド/シリカ複合ナノ粒子の開発　　　　　　　　　　　　　　　
猪瀬智也、中島光一、及川隆洋、鳩山恵一朗、徳永正之、権田幸祐、小林芳男
化学工学会 第４９回秋季大会, 2017年09月

発光性量子ロッド/シリカコア-シェル複合ナノ粒子の作製　　　　　　　　　　　　　　　
上林将也、横川真衣、長谷川雅樹、大倉央、平山裕樹、中島光一、小林芳男
化学工学会 第４９回秋季大会, 2017年09月

高濃度銅ナノ粒子コロイド溶液の調整とその接合特製　　　　　　　　　　　　　　　
須賀悠貴、中島光一、小林芳男、守田俊章、保田雄亮、能川玄也
化学工学会 第４９回秋季大会, 2017年09月

さまざまなニオブ原料を用いたNaNbO3ナノキューブ合成　　　　　　　　　　　　　　　
戸嶋康晴、小林芳男、垣花眞人、中島光一
日本セラミックス協会 第３０回秋季シンポジウム, 2017年09月

CaF2ナノクリスタルの液相合成　　　　　　　　　　　　　　　
中島光一、渋川丞治、小林芳男、垣花眞人
粉体粉末冶金 第１１９回講演大会, 2017年05月

溶液反応化学に立脚したナノキューブ合成　　　　　　　　　　　　　　　
中島 光一
第９回ワークショップ 「固体材料合成および評価技術の新展開」, 2016年09月

SrTiO3ナノキューブ粒子を用いた水分解光触媒の創製と粒子表面の原子配列制御　　　　　　　　　　　　　　　
基盤研究（Ｃ）
2022年04月 - 2025年03月

液相反応化学に立脚したナノキューブ粒子の開発　　　　　　　　　　　　　　　
2020年04月 - 2022年03月

水分解光触媒機能を有するSrTiO3ナノキューブ粒子の創製　　　　　　　　　　　　　　　
科学研究費助成事業 基盤研究（Ｃ）
2019年04月 - 2022年03月

精密微粒子設計に基づく高性能光触媒ナノキューブ粒子の開発　　　　　　　　　　　　　　　
公益財団法人 東電記念財団 研究助成
2018年04月 - 2019年03月

溶液反応化学に立脚したニオブ酸ナトリウムナノキューブの単一粒径化　　　　　　　　　　　　　　　
科学研究費助成事業 基盤研究（Ｃ）
2016年04月 - 2019年03月

ボトムアップ型アプローチによるナノキューブ蛍光体の開発　　　　　　　　　　　　　　　
公益財団法人 泉科学技術振興財団 研究助成
2017年11月 - 2018年10月

精密微粒子設計に基づく高機能ナノキューブ粒子の開発　　　　　　　　　　　　　　　
公益財団法人 中部電気利用基礎研究振興財団 研究助成
2017年04月 - 2018年03月