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Carbonated nanohydroxyapatite from bone waste and its potential as a super adsorbent for removal of toxic ions

関根 由莉奈; 南川 卓也; 山田 鉄兵*; 松村 大樹; 根本 善弘*; 竹口 雅樹*; 杉田 剛; 下山 巖; 香西 直文; 諸岡 聡

Journal of Environmental Chemical Engineering, 9(2), p.105114_1 - 105114_12, 2021/04

 被引用回数:0 パーセンタイル:0(Engineering, Environmental)



Mechanistic study on the removal of Cs from contaminated soil by rapid ion exchange in subcritical water

福田 達弥*; 高橋 亮*; 原 卓飛*; 尾原 幸治*; 加藤 和男*; 松村 大樹; 稲葉 優介*; 中瀬 正彦*; 竹下 健二*

Journal of Nuclear Science and Technology, 58(4), p.399 - 404, 2021/04

 被引用回数:1 パーセンタイル:0.01(Nuclear Science & Technology)

As a result of the Fukushima nuclear power plant accident in March 2011, massive amounts of soil were contaminated with radioactive Cs. To remediate the contaminated soil, we are developing a desorption technique for removing Cs from soil using subcritical water. We found that rapid ion exchange of Cs with multivalent cations in subcritical water is an effective desorption technique. To understand the mechanism and structural aspects of this process, in situ observations of the soil layer in subcritical water were carried out by high-energy X-ray diffraction together with pair distribution function analysis, and extended X-ray absorption fine structure analysis. Both the desorption experiments and structural studies indicated that conformational changes of the layer containing Cs$$^{+}$$ under subcritical water conditions promoted intercalation of the hydrated Mg and trapped Cs$$^{+}$$, which facilitated a rapid ion-exchange reaction of Mg$$^{2+}$$ and Cs$$^{+}$$.


Local Ir dedimerization followed by ligand-hole hopping in X-ray irradiated thiospinel

平賀 晴弘*; 松村 大樹; 堀金 和正*; 水木 純一郎*

Journal of Physics and Chemistry of Solids, 150, p.109870_1 - 109870_8, 2021/03

 被引用回数:0 パーセンタイル:0(Chemistry, Multidisciplinary)

The extended X-ray-absorption fine structure of a spinel CuIr$$_{2}$$(S$$_{0.95}$$Se$$_{0.05}$$)$$_{4}$$ powder sample, which has the charge-ordered temperature $$T_{rm{CO}}$$ = 190 K, was determined at the Ir $$L_{3}$$ edge for a wide temperature range. All the local structure parameters on the Ir-Ir bonds signified the second structural change at $$T^{*} sim$$ 70 K. Remarkably, the number of Ir dimers decreased by $$sim$$ 10% below $$T^{*}$$, which indicates partial dedimerization by X-ray irradiation. We also reanalyzed the resistance data of CuIr$$_{2}$$S$$_{4}$$ with the variable-range hopping model by focusing on the density of states. The X-ray-induced decrease in resistance was quantitatively explained as a result of the increase in the density of states, which was attributed to the release of holes from the 10%-dedimerized Ir ions. We suppose that the released holes hop over the ligand chalcogen site.


Coordination number regulation of molybdenum single-atom nanozyme peroxidase-like specificity

Wang, Y.*; Jia, G.*; Cui, X.*; Zhao, X.*; Zhang, Q.*; Gu, L.*; Zheng, L.*; Li, L. H.*; Wu, Q.*; Singh, D. J.*; et al.

Chem, 7(2), p.436 - 449, 2021/02

 被引用回数:13 パーセンタイル:99.48(Chemistry, Multidisciplinary)

Nanozymes are promising alternatives to natural enzymes, but their use remains limited owing to poor specificity. Overcoming this is extremely challenging due to the intrinsic structural complexity of these systems. We report theoretical design and experimental realization of a series of heterogeneous molybdenum single-atom nanozymes (named Mo$$_{rm{SA}}$$-N$$_{x}$$-C), wherein we find that the peroxidase-like specificity is well regulated by the coordination numbers of single Mo sites. The resulting Mo$$_{rm{SA}}$$-N$$_{3}$$-C catalyst shows exclusive peroxidase-like behavior. It achieves this behavior via a homolytic pathway, whereas Mo$$_{rm{SA}}$$-N$$_{2}$$-C and Mo$$_{rm{SA}}$$-N$$_{4}$$-C catalysts have a different heterolytic pathway. The mechanism of this coordination-number-dependent enzymatic specificity is attributed to geometrical structure differences and orientation relationships of the frontier molecular orbitals.



松村 大樹; 加藤 和男*

放射光, 34(1), p.3 - 11, 2021/01

分散型光学系を用いたX線吸収微細構造(X-ray absorption fine structure: XAFS)分光法は、機械的に動く機構が無いという特徴から、高い実時間分解能と高い相対精度が期待できる。我々は「その場」かつ「時間分解」XAFS測定システムを立ち上げ、多くの反応系に適用させ、化学反応の真の姿を理解するという目的の下、研究開発を行ってきた。分散型光学系によるXAFS測定のこれまでの研究を概説すると共に、手がけたいくつかの研究例を説明する。


General synthesis of single-atom catalysts for hydrogen evolution reactions and room-temperature Na-S batteries

Lai, W.-H.*; Wang, H.*; Zheng, L.*; Jiang, Q.*; Yan, Z.-C.*; Wang, L.*; 吉川 浩史*; 松村 大樹; Sun, Q.*; Wang, Y.-X.*; et al.

Angewandte Chemie; International Edition, 59(49), p.22171 - 22178, 2020/12

 被引用回数:16 パーセンタイル:89.25(Chemistry, Multidisciplinary)

Herein, we report a comprehensive strategy to synthesize a full range of single-atom metals on carbon matrix, including V, Mn, Fe, Co, Ni, Cu, Ge, Mo, Ru, Rh, Pd, Ag, In, Sn, W, Ir, Pt, Pb, and Bi. The extensive applications of various single-atom catalysts (SACs) are manifested via their ability to electro-catalyze typical hydrogen evolution reactions (HER) and conversion reactions in novel room-temperature sodium sulfur batteries (RT-Na-S). The enhanced performances for these electrochemical reactions arisen from the ability of different single active atoms on local structures to tune their electronic configuration. Significantly, the electrocatalytic behaviors of diverse SACs, assisted by density functional theory calculations, are systematically revealed by in situ synchrotron X-ray diffraction and in situ transmission electronic microscopy, providing a strategic library for the general synthesis and extensive applications of SACs in energy conversion and storage.


Application of an augmentation method to MCR-ALS analysis for XAFS and Raman data matrices in the structural change of isopolymolybdates

佐伯 盛久*; 蓬田 匠; 松村 大樹; 斉藤 拓巳*; 中西 隆造*; 辻 卓也; 大場 弘則*

Analytical Sciences, 36(11), p.1371 - 1378, 2020/11

 被引用回数:0 パーセンタイル:0(Chemistry, Analytical)

モリブデンイオンMoO$$_{4}$$$$^{2-}$$水溶液に酸を加えると、複数のモリブデン原子が酸素を介して結合したポリモリブデン酸が形成され、さらに酸濃度に応じてポリモリブデン酸の化学形態は大きく変化する。我々は、これまで研究例の少なかった高酸性水溶液中(0.15-4.0M)でのポリモリブデン酸の化学形態を、ラマン分光法およびX線吸収微細構造(XAFS)分光法により調べ、測定したスペクトルを多変量スペクトル分解法(MCR-ALS)により解析した。MCR-ALS解析では実験データ解析により得られるスペクトルの任意性が問題になり、XAFSデータのみの解析ではこれが顕著になるが、XAFSデータとラマンデータを同時にMCR-ALS解析することで、信頼性の高い3成分のXAFSスペクトルを得ることに成功した。構造解析の結果から、硝酸濃度が高くなるにつれポリモリブデン酸の化学種が[Mo$$_{36}$$O$$_{112}$$(H$$_{2}$$O)$$_{16}$$]$$^{2+}$$$$rightarrow $$[Mo$$_{2}$$O$$_{5}$$(H$$_{2}$$O)$$_{6}$$]$$^{2+}$$$$rightarrow $$[HMoO$$_{3}$$(H$$_{2}$$O)$$_{3}$$]$$^{+}$$へと変化する様子を明らかにした。



松村 大樹

触媒の劣化対策,長寿命化, p.205 - 212, 2020/11

東日本大震災に伴う東京電力福島第一原子力発電所での事故においては、原子力格納容器内部にて水素が大量に発生し、それが外部へと漏れ出ることにより水素爆発を誘発させ、放射能物質の環境への拡散を引き起こす要因となった。金属微粒子触媒を利用した水素-酸素再結合反応の利用は、放出された水素と環境中に存在する酸素とを緩やかに反応させ、水素が爆発限界濃度に達する以前に水素ガスを消費させ水素濃度の低減化を図ろうとするもので、外部電源が存在しない環境下においても効果的に水素を除去するシステムを構築できる可能性があり、より幅広い環境下における実用化が求められている。触媒の長寿命化という観点からの開発には、触媒の劣化の要因を知ることが必要である。X線吸収分光(X-ray absorption fine structure: XAFS)法は担持微粒子触媒の構造解析手法として、「その場」測定に最も適した手法と言っても過言ではない。各種雰囲気を制御したXAFS法による「その場」観測を行うことで、反応と構造との関連を付け、触媒劣化の真の構造要因を探り、触媒の長寿命化への道筋を作ることができる。


Ultra-fine CeO$$_{2}$$ particles triggered strong interaction with LaFeO$$_{3}$$ framework for total and preferential CO oxidation

Zheng, Y.*; Xiao, H.*; Li, K.*; Wang, Y.*; Li, Y.*; Wei, Y.*; Zhu, X.*; Li, H.-W.*; 松村 大樹; Guo, B.*; et al.

ACS Applied Materials & Interfaces, 12(37), p.42274 - 42284, 2020/09

 被引用回数:4 パーセンタイル:51.8(Nanoscience & Nanotechnology)

Interactions between the active components with the support are one of the fundamentally factors in determining the catalytic performance of a catalyst. In this study, we investigated the interaction between CeO$$_{2}$$ and LaFeO$$_{3}$$, the two important oxygen storage materials in catalysis area, by tuning the sizes of CeO$$_{2}$$ particles and highlight a two-fold effect of the strong oxide-oxide interaction in determining the catalytic activity and selectivity for preferential CO oxidation in hydrogen feeds. It is found that the anchoring of ultra-fine CeO$$_{2}$$ particles at the framework of three-dimensional-ordered macroporous LaFeO$$_{3}$$ surface results in a strong interaction between the two oxides that induces the formation of abundant uncoordinated cations and oxygen vacancy at the interface. This discovery demonstrates that in hybrid oxide-based catalysts, tuning the interaction among different components is essential for balancing the catalytic activity and selectivity.


Structural significance of nickel sites in aluminosilicate glasses

門 力也*; 岸 哲生*; Lelong, G.*; Galoisy, L.*; 松村 大樹; Calas, G.*; 矢野 哲司*

Journal of Non-Crystalline Solids, 539, p.120070_1 - 120070_8, 2020/07

 被引用回数:1 パーセンタイル:0.01(Materials Science, Ceramics)

We use Ni ions as a structural probe to investigate the influence of modifier cations on the structure of aluminosilicate glasses. The color of these glasses varies with the nature of the cations present in glass. Structural origin of this change is investigated by optical absorption and X-ray absorption spectroscopies. Our results reveal pronounced changes in Ni coordination. Tetrahedra Ni$$^{2+}$$ ins present in all these glasses and Ni$$^{2+}$$ in 5-fold coordination site also appears. There is a weak contribution from octahedral Ni$$^{2+}$$. The concentration of tetrahedral Ni$$^{2+}$$ deduced from the optical absorption spectroscopy increases with decreasing cation field strength, explaining the variation of color from yellow and brown to purple. This is in line with X-ray absorption spectroscopy data. Cation-oxygen distances and site symmetry indicate a similar structural behavior of Mg$$^{2+}$$ and Ni$$^{2+}$$, being a good structural probe to Mg.


Unusual redox behavior of ruthenocene confined in the micropores of activated carbon

糸井 弘行*; Ninomiya, Takeru*; 長谷川 英之*; Maki, Shintaro*; Sakakibara, Akihiro*; 鈴木 隆太郎*; 笠井 湧斗*; 岩田 博之*; 松村 大樹; 大和田 真生*; et al.

Journal of Physical Chemistry C, 124(28), p.15205 - 15215, 2020/07

 被引用回数:4 パーセンタイル:61.86(Chemistry, Physical)

We demonstrate reversible charge/discharge in ruthenocene, RuCp$$_{2}$$ (Cp = $$eta^5$$-C$$_{5}$$H$$_{5}$$), using activated carbon (AC) as a support. Upon subsequent electrochemical oxidation using an aqueous H$$_{2}$$SO$$_{4}$$ electrolyte, the clusters are disassembled and the RuCp$$_{2}$$ molecules are finely dispersed in the micropores. The resulting RuCp$$_{2}$$ has a large contact area with conductive carbon surfaces, thereby realizing rapid charge transfer at the contact interface. Consequently, rapid charge storage occurs via the reversible redox reaction of the supported RuCp$$_{2}$$ in aqueous H$$_{2}$$SO$$_{4}$$ without dimerization or disproportionation reactions, which is confirmed by X-ray absorption spectroscopy. Since hybridization can produce different properties of the host and guest materials, their infinite combinations would have the possibility to yield properties far surpassing those of existing materials.


Synthesis and characterization of iodovanadinite using PdI$$_{2}$$, an iodine source for the immobilisation of radioiodine

Johnstone, E. V.*; Bailey, D. J.*; Lawson, S.*; Stennett, M. C.*; Corkhill, C. L.*; Kim, M.*; Heo, J.*; 松村 大樹; Hyatt, N. C.*

RSC Advances (Internet), 10(42), p.25116 - 25124, 2020/07

 被引用回数:0 パーセンタイル:0(Chemistry, Multidisciplinary)

The synthesis of a palladium-containing iodovanadinite derivative, hypothetically "PdPb$$_{9}$$(VO$$_{4}$$)$$_{6}$$I$$_{2}$$", was attempted using PdI$$_{2}$$ as a source of iodine in searching for a novel waste form for radioiodine. The resulting products were characterized using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, IR spectroscopy, thermal analysis and Pd K XANES. Results showed that PdI$$_{2}$$ can function as a sacrificial iodine source for the formation of iodovanadinite, prototypically Pb$$_{10}$$(VO$$_{4}$$)$$_{6}$$I$$_{2}$$, however, the incorporation of Pd into this phase was not definitively observed. Overall, the key novelty and importance of this work is in demonstrating a method for direct immobilisation of undissolved PdI$$_{2}$$ from nuclear fuel reprocessing, in a composite wasteform in which I-129 is immobilised within a durable iodovandinite ceramic, encapsulating Pd metal.


Porous metal-organic frameworks containing reversible disulfide linkages as cathode materials for lithium-ion batteries

清水 剛志*; Wang, H.*; 松村 大樹; 光原 圭*; 太田 俊明*; 吉川 浩史*

ChemSusChem, 13(9), p.2256 - 2263, 2020/05

 被引用回数:9 パーセンタイル:85.53(Chemistry, Multidisciplinary)

Three porous disulfide-ligand-containing metal-organic frameworks (DS-MOFs) and two nonporous coordination polymers with disulfide ligands (DS-CPs) with various structural dimensionalities were used as cathode active materials in lithium batteries. Charge/discharge performance examinations revealed that only porous DS-MOF-based batteries exhibited significant capacities close to the theoretical values, which was ascribed to the insertion of electrolyte ions into the DS-MOFs. Battery reactions were probed by instrumental analyses. The dual redox reactions of metal ions and disulfide ligands in the MOFs resulted in higher capacities, and the presence of reversible electrochemically dynamic S-S bonds stabilized the cycling performance. Thus, the strategy of S-S moiety trapping in MOFs and the obtained correlation between the structural features and battery performance could contribute to the design of high-performance MOF-based batteries and the practical realization of Li-S batteries.


Sorption behavior of selenide on montmorillonite

杉浦 佑樹; 戸村 努*; 石寺 孝充; 土井 玲祐; Francisco, P. C. M.; 塩飽 秀啓; 小林 徹; 松村 大樹; 高橋 嘉夫*; 舘 幸男

Journal of Radioanalytical and Nuclear Chemistry, 324(2), p.615 - 622, 2020/05

 被引用回数:1 パーセンタイル:0.01(Chemistry, Analytical)

Batch sorption experiments were performed to investigate the sorption mechanism of Se on montmorillonite under reducing conditions in deep geological environments. Based on Eh-pH diagrams and ultraviolet-visible spectra, Se was dissolved as selenide (Se(-II)) anions under the experimental conditions. The distribution coefficients ($$K_{rm d}$$; m$$^{3}$$ kg$$^{-1}$$) of Se(-II) indicated ionic strength independence and slight pH dependence. The $$K_{rm d}$$ values of Se(-II) were higher than those of Se(IV), which also exists as an anionic species. X-ray absorption near edge spectroscopy showed that the oxidation state of Se-sorbed on montmorillonite was zero even though selenide remained in the solution. These results suggest that Se(-II) was oxidized and precipitated on the montmorillonite surface. Therefore, it is implied that a redox reaction on the montmorillonite surface contributed to high $$K_{rm d}$$ values for Se(-II).


Hydrogen absorption and desorption on Rh nanoparticles revealed by ${it in situ}$ dispersive X-ray absorption fine structure spectroscopy

Song, C.*; Seo, O.*; 松村 大樹; 廣井 慧*; Cui, Y.-T.*; Kim, J.*; Chen, Y.*; Tayal, A.*; 草田 康平*; 小林 浩和*; et al.

RSC Advances (Internet), 10(34), p.19751 - 19758, 2020/05

 被引用回数:0 パーセンタイル:0(Chemistry, Multidisciplinary)

To unveil the origin of the hydrogen-storage properties of rhodium nanoparticles (Rh NPs), we investigated the dynamical structural change of Rh NPs using ${it in situ}$ dispersive X-ray absorption fine structure spectroscopy (XAFS). The variation of the Rh-Rh interatomic distance and Debye-Waller factor of Rh NPs with a size of 4.0 and 10.5 nm during hydrogen absorption and desorption suggested that they have a different mechanism for hydrogen absorption, which is that the hydrogen absorption on the inner site has a greater contribution than that on a surface for Rh 4.0 nm. In the case of Rh 10.5 nm, it is opposed to Rh 4.0 nm. This study demonstrates a powerful ${it in situ}$ XAFS method for observing small local structural changes of metal nanoparticles and its importance for understanding of the hydrogen-absorption properties of Rh NPs with an interesting hydrogenation mechanism.


Changes in electronic structure of carbon supports for Pt catalysts induced by vacancy formation due to Ar$$^{+}$$ irradiation

岡崎 宏之*; 垣谷 健太*; 木全 哲也*; 出崎 亮*; 越川 博*; 松村 大樹; 山本 春也*; 八巻 徹也*

Journal of Chemical Physics, 152(12), p.124708_1 - 124708_5, 2020/03

 被引用回数:1 パーセンタイル:0.01(Chemistry, Physical)

X-ray absorption spectroscopy measurements were performed for the C K-edge of Pt nanoparticles on Ar$$^{+}$$-irradiated carbon supports in order to elucidate the origin of improved catalyst performance after the introduction of vacancies into the carbon support. We observed a change in the electronic structure at the interface between the Pt nanoparticles and the carbon support after vacancy introduction, which is in good agreement with theoretical results. The results indicated that vacancy introduction resulted in a drastic change in the Pt-C interactions, which likely affected the d-band center of the Pt nanoparticles and led to the enhancement of the oxygen reduction reaction in catalysts.


Zeolitic vanadomolybdates as high-performance cathode-active materials for sodium-ion batteries

Zhang, Z,*; Wang, H.*; 吉川 浩史*; 松村 大樹; 畑尾 秀哉*; 石川 理史*; 上田 渉*

ACS Applied Materials & Interfaces, 12(5), p.6056 - 6063, 2020/02

 被引用回数:2 パーセンタイル:38.31(Nanoscience & Nanotechnology)

Developing new cathode-active materials for rechargeable batteries is important to fulfill the growing demands of energy transformation, storage, and utilization. Zeolitic transition-metal oxides based on vanadomolybdate, constructed by pentagon metal-oxygen clusters as building blocks and metal ions as linkers in a trigonal symmetry, are good candidates for cathodes of Na rechargeable batteries. The material is activated via amorphization of the crystal structure in the ab plane during discharging process, keeping the molecular structure of the building blocks stable, which causes high specific capacity and good cycle performance.



米田 安宏; 吉越 章隆; 竹田 幸治; 塩飽 秀啓; 松村 大樹; 菖蒲 敬久; 田村 和久

まてりあ, 58(12), p.763 - 769, 2019/12



X-ray absorption spectroscopy and magnetocaloric study of Pr$$_{1-x}$$Sr$$_{x}$$CoO$$_{3}$$ (0$$leq x leq$$0.5)

松村 大樹; 辻 卓也; 吉井 賢資

Materials Chemistry and Physics, 238, p.121885_1 - 121885_5, 2019/12

 被引用回数:0 パーセンタイル:0(Materials Science, Multidisciplinary)

ペロブスカイトPr$$_{1-x}$$Sr$$_{x}$$CoO$$_{3}$$(0$$leq x leq$$0.5)についてX線吸収分光測定を行うとともに、x=0.5で観測される110Kの磁気異常の起源を探るため磁気熱量効果測定を行った。Co${it K}$吸収端のX線吸収測定からは、xが増えるとともにCoの原子価が増加し、Co-O結合距離が縮まることが分かった。また、CoO$$_{6}$$多面体の歪みも増大することが分かった。Co-O結合距離の縮み方は、xが大きいほど大きいことも分かった。測定温度範囲である17-300Kでは、Co${it K}$吸収端の吸収スペクトルには異常は見られなかった。磁気熱量効果の結果と合わせ、110Kの異常は磁気構造の変化であることが分かった。


Structural approach to understanding the solubility of metal hydroxides

小林 大志*; 中嶋 翔梧*; 元川 竜平; 松村 大樹; 斉藤 拓巳*; 佐々木 隆之*

Langmuir, 35(24), p.7995 - 8006, 2019/06

 被引用回数:1 パーセンタイル:9.61(Chemistry, Multidisciplinary)

We report the hierarchical structure of zirconium hydroxide after aging at different temperatures to elucidate the factors governing zirconium solubility in aqueous solutions. Zirconium hydroxide solid phases after aging at 25, 40, 60, and 90$$^{circ}$$C under acidic to alkaline conditions were investigated using extended X-ray absorption fine structure (EXAFS) and wide- and small-angle X-ray scattering (WAXS and SAXS) techniques to reveal the bulk and surface structures of the solid phases from the nanoscale to submicroscale. After aging at 25 $$^{circ}$$C, the fundamental building unit of the solid phase was a zirconium hydroxide tetramer. The tetramers formed primary particles approximately 3 nm in size, which in turn formed aggregates hundreds of nanometers in size. This hierarchical structure was found to be stable up to 60 $$^{circ}$$C under acidic and neutral conditions and up to 40 $$^{circ}$$C under alkaline conditions. After aging at 90 $$^{circ}$$C under acidic conditions and at 60 and 90 $$^{circ}$$C under alkaline conditions, the WAXS and EXAFS measurements suggested the crystallization of the solid phase. The transformation of the solid-phase structure by temperature was discussed in relation to the solubility product to understand the solubility-limiting solid phase. The solubility of zirconium hydroxide after aging at different temperatures was governed not only by the size of the primary particles, but also by their surface configuration.

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