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中瀬 正彦*; 中沢 亮太*; 三島 理愛
Next Chemical Engineering (Internet), 2, p.100051_1 - 100051_14, 2026/06
The separation of Platinum Group Metals (PGMs) is critical across various fields, including industrial metal recovery and nuclear waste management. This study rigorously examines the separation mechanisms of PGMs using Aluminum Hexacyanoferrate (AlHCF) by employing some analytical techniques. The mechanism involves not only simple adsorption but also the dissolution of AlHCF, leading to PGM ion precipitation and elution of components, as well as adsorption onto the AlHCF surface. We conducted X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray absorption fine structure (XAFS), and pair distribution function (PDF) to thoroughly investigate the structural and chemical changes in AlHCF and FeHCF before and after PGM adsorption. Our findings reveal that Pd
ions replace Fe in AlHCF, preserving the ferrocyanide framework and the adsorption of Ru and Rh. In contrast, Ru and Rh adsorption results in broadened XRD pattern without initial AlHCF structure, suggesting the formation of amorphous precipitates through complexation with dissolved ions. By detailing these mechanisms, this study highlights the efficacy of AlHCF as a PGM separation agent and offers valuable insights for the improvement of useful metal recovery processes.
山本 孟*; 越智 啓伍*; 青山 拓也*; 石井 賢司*; 松村 大樹; 辻 卓也; 大串 研也*; 虻川 匡司*
ACS Omega (Internet), 11(14), p.22093 - 22098, 2026/04
Ilmenite-type CuVO is a promising compound for exploring novel spin and orbital states, as Cu(3d
) and V
(3d
) ions each form a honeycomb lattice. In this study, we synthesized triclinic ilmenite-type CuVO using a high-pressure and high-temperature method and investigated its spin and orbital states through synchrotron X-ray diffraction and measurements of electrical resistivity, magnetic susceptibility, and specific heat. The Cu ions exhibit the Jahn-Teller effect, leading to the triclinic distortion. This Jahn-Teller distortion hinders the formation of static V-V dimers, in contrast to other ilmenite-type vanadium oxides in which V-V dimerization is observed. These findings highlight triclinic ilmenite-type CuVO as a fascinating system in which each cation exhibits characteristic spin and orbital states.
谷田 肇; 岡本 芳浩; 秋山 大輔*; 桐島 陽*
X線分析の進歩,57, p.249 - 259, 2026/03
約1
m
に集光したマイクロビームを使用し、同一視野のXAFS/XRF/XRD測定を行うことにより、元素組成、結晶相、化学状態を分析する手法を確立した。分析対象試料は高レベル放射性廃液の模擬ガラス固化プロセスで問題になっている、試料中に析出するモリブデン酸塩結晶、いわゆるイエローフェーズと、原子炉の事故で生成する燃料デブリの模擬試料である。イエローフェーズ試料についてはモリブデンの化学状態がガラス相と違うことなどを明らかにできることを確認した。また、多成分、多相系で、数十ミクロン単位で場所ごとに組成比が変わり、均一な固溶体を形成しない模擬燃料デブリ試料については、選択的にUリッチ相中のUの化学状態を明らかにできることを確認した。
小澤 沙記*; 塩沢 優大*; 西條 佳孝*; 宮嶋 達也*; 松村 大樹; 辻 卓也; 中瀬 正彦*; 前原 輝敬*
Journal of the American Ceramic Society, 109(3), p.e70621_1 - e70621_10, 2026/03
被引用回数：1 パーセンタイル：0.00(Materials Science, Ceramics)The optical properties of glass are strongly influenced by the redox states of trace multivalent elements. Ce ions are commonly added to soda-lime glass to remove Fe-induced coloration via the redox reaction Ce + Fe 
Ce
+ Fe during cooling. Herein, the redox dynamics of cerium ions in soda-lime glass melts during model industrial cooling processes (from 1523 K at 20 K
min
) were investigated using in situ time-resolved Ce K-edge dispersive X-ray absorption fine-structure (DXAFS) spectroscopy. To evaluate the effect of the iron concentration, three soda-lime glass samples containing 2 mass% CeO
were examined: Fe-free, Fe-05 (0.5 mass% FeO), and Fe-20 (2.0 mass% FeO). Above 1383 K, the Ce/total Ce ratio remained stable for all samples, showing no significant change during cooling. Below 1383 K, the ratio decreased for the Fe-free glass, indicating the oxidation of Ce ions, and increased for the Fe-containing glass owing to the reduction of Ce ions. The temperature dependence of the redox change (
Ce redox) showed Fe-dependent behavior: Fe-20 exhibited more pronounced Ce reduction above 1200 K, while Fe-05 showed accelerated changes mainly below approximately 1100 K. These results indicate that cerium oxidation in Fe-free glass is strongly influenced by oxygen transport limitations, while cerium reduction is closely associated with availability of Fe ions, providing quantitative insights into the control of Ce-based decolorization during industrial cooling.
松村 大樹; 辻 卓也; 瀬古 典明*; 他5名*
Journal of Radioanalytical and Nuclear Chemistry, 335(2), p.1543 - 1552, 2026/02
被引用回数：0 パーセンタイル：0.00(Chemistry, Analytical)The COVID-19 pandemic has underscored the need for protective materials with rapid and durable antiviral properties. We developed silver (Ag)-immobilized fabrics via radiation-induced graft polymerization and tested their activity against SARS-CoV-2. The fabrics reduced 40,000 viral particles to below detection within one hour, showed no Ag leaching after 24 h in water, and retained complete antiviral performance after one year of storage. These findings demonstrate the long-term stability and strong potential of Ag-immobilized fabrics for industrial use in protective equipment.
松村 大樹; 石井 賢司*; 田中 裕久*; 水木 純一郎*
放射光, 39(1), p.28 - 36, 2026/01
燃料電池の開発は二酸化炭素発生抑制のためにも重要な研究課題である。中でも電極反応における酸素還元反応は、電池全体の律速過程であることから、詳しい理解が求められる。高分解能X線吸収分光法を適用し、電極反応の「その場」観察を行うことで、炭素担持白金微粒子(Pt/C)電極触媒に対して表面吸着種の電位依存観測を実施した。その結果、これまで実触媒では同定されていなかった、酸素還元反応の反応中間体としての分子状酸素吸着種の存在を、酸性環境下でもアルカリ性環境下でも見出し、酸素還元反応の理解を一歩進めることができた。
Wang, M.*; 辻 卓也; 松村 大樹; 坂牛 健*; 他9名*
Journal of Physical Chemistry C, 130(2), p.931 - 941, 2026/01
被引用回数：0 パーセンタイル：0.00(Chemistry, Physical)Understanding how compositional complexity influences electrocatalytic kinetics remains a major challenge in the design of multicomponent materials. The multifaceted interactions between constituent elements are able to obscure the factors governing kinetics of electrode processes. Here, we introduce a small compositional change to modulate the rate-determining step of the oxygen evolution reaction (OER) by tuning the binding energies of key intermediates. We combine advanced characterization, including 
electrochemical X-ray absorption spectroscopy, with first-principles calculations to demonstrate that the drastic enhancement in OER activity of MnFeNi-based materials is driven by synergistic interactions among the constituent elements. This enhancement stems from targeted modulation of intrinsic reaction pathways, shifting the rate-determining step via controlled stabilization of key intermediates. Our findings introduce a clear viewpoint for understanding how compositional tuning governs kinetics in complex electrocatalytic systems, offering new design principles for next-generation electrochemical materials.
上田 祐生; 小林 徹; 中村 聡志; 伴 康俊; 金田 結依; 生田目 望; Micheau, C.; 徳永 紘平; 中部 倫太郎; 金子 政志*; et al.
Langmuir, 42(1), p.1613 - 1626, 2026/01
被引用回数：0 パーセンタイル：0.00(Chemistry, Multidisciplinary)溶媒抽出系における金属イオンの選択性を支配する構造要因の理解は、高レベル放射性廃棄物の分離変換プロセスを高度化する上で極めて重要である。本研究では、代表的なランタニドとしてランタン(La)とネオジム(Nd)を対象に、ニトリロトリアセトアミド(NTAamide)抽出剤のアルキル側鎖分岐度が抽出挙動に及ぼす影響を系統的に調査した。分子量は同一だがアルキル分岐度の異なる4種類の抽出剤(いずれもアミド鎖の1本が炭素数8)を用い、硝酸濃度に対する分配比を測定した。さらに、LaおよびNdの局所配位構造を拡張X線吸収微細構造(EXAFS)で解析し、有機相における超分子的凝集挙動を小角中性子散乱(SANS)で評価した。その結果、EXAFS解析から、LaおよびNdの内圏配位環境はアルキル分岐度の影響をほとんど受けないことが明らかとなった。一方、SANS解析からは、分岐の少ない抽出剤ほど低硝酸濃度で大きな凝集体を形成し、特にNdにおいては凝集体形成が抽出を促進し、難溶性錯体の沈殿を防いでいることが示された。これらの結果は、アルキル分岐度が超分子的凝集挙動を強く制御し、それが抽出挙動を支配していることを示している。本研究は、ランタニドおよびアクチニドの溶媒抽出において、選択性向上のための新しい設計概念として「ナノスケール構造制御」の可能性を示すものである。
MnCoNiCu)VO
山本 孟*; 辻 卓也; 松村 大樹; 他16名*
Inorganic Chemistry, 64(34), p.17496 - 17502, 2025/08
被引用回数：1 パーセンタイル：0.00(Chemistry, Inorganic & Nuclear)V-V dimerization in ilmenite-type vanadium oxides is an intriguing phenomenon that induces structural and metal-to-insulator transitions. Herein, we report the high-pressure synthesis, crystal structure, and electronic states of high-entropy ilmenite-type (MgMnCoNiCu)VO. Although all the parent ilmenite-type compounds exhibit triclinic (
) symmetry, this compound crystallizes in a rhombohedral (
) structure, indicating the absence of V-V dimer ordering. The temperature dependence of the resistivity below room temperature follows a variable-range hopping conduction mechanism, suggesting the presence of short-range V-V dimer ordering. Magnetic susceptibility and heat capacity measurements revealed multi-step spin-glass transitions. This study demonstrates that a high-entropy composition hinders electronic and magnetic long-range ordering due to severe lattice distortions and competition between magnetic exchange interactions.
O and/or SiO for methanol synthesis; Deciphering the additive-induced boost in catalytic performance by XAFSIwasaki, Kosei*; Ashida, Yuya*; 松村 大樹; Kawakami, Kotaro*; Shibuya, Kana*; Tazawa, Masaru*; 辻 卓也; Shimizu, Hajime*
Journal of CO Utilization, 97, p.103111_1 - 103111_9, 2025/07
The development of active, long-lived methanol synthesis catalysts can be expedited by thoroughly understanding the operating mechanisms of promoter additives. SiO serves as an effective support and promoter for Cu/ZnO-type methanol synthesis catalysts; however, it has not been studied as extensively as the industrially predominant AlO, despite being similarly potent. Therefore, we conducted X-ray absorption fine structure predominant AlO, despite being similarly potent. Therefore, we conducted X-ray absorption fine structure studies to probe the effects of incorporating AlO and SiO additives into Cu/ZnO-based heterogeneous catalysts. The results revealed that the additive elements primarily affected the ability of the Zn species to generate oxygen vacancies by distorting the local structure around element-doped ZnO and that the number of oxygen vacancies correlated to the catalytic activity. Additionally, the oxygen vacancies in ZnO in the Al/Si-incorporated catalysts diminished under catalytic reaction conditions, thereby providing information on the deactivation of catalytic reactions. Our findings can facilitate the development of highly active industrial-grade methanol synthesis catalysts.
田中 裕久*; 松村 大樹; 他8名*
International Journal of Hydrogen Energy, 141, p.1317 - 1327, 2025/06
被引用回数：1 パーセンタイル：19.59(Chemistry, Physical)The safe removal, transportation, and long-term storage of fuel debris in the decommissioning of Fukushima Daiichi is the biggest challenge facing Japan. In the nuclear power field, passive autocatalytic recombiners (PARs) have become established as a technology to prevent hydrogen explosions inside the containment vessel. To utilize PAR as a measure to reduce the concentration of hydrogen generated in the fuel debris storage canister, which is currently an issue, it is required to perform in a sealed environment with high doses of radiation, low temperature, and high humidity, and there are many challenges different from conventional PAR. A honeycomb-shaped catalyst based on automotive catalyst technology has been newly designed as a PAR, and research has been conducted to solve unique problems such as high dose radiation, low temperature, high humidity, coexistence of hydrogen and low oxygen, and catalyst poisons. This paper summarizes the challenges of hydrogen generation in a sealed container, the results of research, and a guide to how to use the PAR for fuel debris storage canisters.
田中 裕久*; 松村 大樹; 他10名*
International Journal of Hydrogen Energy, 141, p.1088 - 1097, 2025/06
被引用回数：1 パーセンタイル：19.59(Chemistry, Physical)Global efforts are being made to decarbonize the energy sector. Liquefied (cryogenic) hydrogen is suitable for large-scale storage and transportation due to its high storage density, so it is likely to play a fundamental role in the future hydrogen economy. The STACY project, "Towards the Safe Storage and Transport of Cryogenic Hydrogen", is investigating safety aspects of liquid hydrogen in order to overcome potential safety risks. Research is being conducted into passive autocatalytic recombiners using cutting-edge catalyst technology to enable them to be used in conditions where liquid hydrogen escapes, evaporates and forms a cold (
50
C) explosive gas mixture with the ambient air. To this end, the crystal structure of the catalyst was designed at the atomic level, an actual catalyst was prototyped, and repeated tests were carried out on a laboratory scale and in a large reaction vessel. Progress has been made in developing catalysts that can oxidize hydrogen even at very low temperatures, high expansion, and low-oxygen environments, are resistant to catalyst poisons, and can prevent spontaneous unintended ignition. The tested catalyst technologies use different carrier materials (alumina and ceria) to control the surface state of precious metals and suppress hydrogen ignition through a multilevel configuration.
頓名 龍太郎*; 佐々木 隆之*; 岡本 芳浩; 小林 大志*
Journal of Nuclear Materials, 612, p.155820_1 - 155820_11, 2025/06
被引用回数：3 パーセンタイル：82.48(Materials Science, Multidisciplinary)福島第一原子力発電所事故による燃料デブリ中の主なウラン固相である(U,Zr)Oの溶解挙動を、大気条件下で熱力学的および速度論的に調べた。湿式化学法によりZrが均一に固溶した立方晶(U,Zr)Oサンプルを調製し、静的バッチ浸漬試験を実施した。UとZrの溶解度がそれぞれの濃度を超える強酸性条件では、両元素の一致した溶解が観察され、(U,Zr)OはUOと同じ速度で溶解した。Uの溶解度がその濃度よりも高く、Zrはより低い溶解度で定常状態に達する中酸性条件では、(U,Zr)OからのUの溶解速度はUOに比べて低下した。シュウ酸の存在下では、錯体形成によりZrの溶解度が上昇したが、(U,Zr)OからのUの溶解速度は低下しなかった。これは、(U,Zr)O中のZrが、Zrの溶解度が低い条件下で固体表面上に2次固相を形成し、Uの酸化溶解を抑制したことを示唆している。
Fablet, L.*; P
drot, M.*; Choueikani, F.*; Kieffer, I.*; Proux, O.*; Pierson-Wickmann, A.-C.*; Cagniart, V.*; 蓬田 匠; Marsac, R.*
Environmental Science; Nano, 12(5), p.2815 - 2827, 2025/05
被引用回数：3 パーセンタイル：62.85(Chemistry, Multidisciplinary)ニッケル(Ni)は環境中に遍在する微量元素である。Niは酸化鉄ナノ粒子との親和性が高く、土壌や水中から酸化鉄ナノ粒子、特に環境中に普遍的に存在する磁鉄鉱によって除去することができれば、環境浄化のための新たな戦略の1つとなり、その研究の意義は大きい。しかし、磁鉄鉱の化学量論(Fe(II)とFe(III)の比率)を制御することが困難であるため、Niと磁鉄鉱の相互作用は十分に理解されていなかった。そこで本研究では、異なるFe(II)とFe(III)の比率を持つ磁鉄鉱ナノ粒子を用い、吸着実験とX線吸収分光法によって溶液中と嫌気雰囲気下におけるNiと磁鉄鉱の相互作用を調べた。この研究により明らかにされた磁鉄鉱とNiの相互作用は、将来的にNi汚染の環境浄化戦略を立案する上で重要な知見となりうる。
上田 祐生; Micheau, C.; 元川 竜平
ファインケミカル, 54(5), p.53 - 60, 2025/05
持続可能な社会を実現するためには金属資源のリサイクルが重要である。高濃度の金属イオンを取り扱う抽出操作では、プロセスの安全な運転を阻害する油相の相分離(第三相の生成)が長年の課題であった。本稿では、フルオラス化合物の強力な疎水性を利用した、第三相を生成させない新たな抽出系開発におけるこれまでの成果をまとめた。
Pt
Ga
with a honeycomb structure using extended X-ray absorption fine structure松本 裕司*; 渡部 悠貴*; Iesari, F.*; 大角 将勝*; 太田 玖吾*; 芳賀 芳範; 畑田 圭介*; 岡島 敏浩*
Metals, 15(4), p.436_1 - 436_13, 2025/04
被引用回数：0 パーセンタイル：0.00(Materials Science, Multidisciplinary)A heavy fermion system CePtGa is studied by the extended X-ray absorption fine structure (EXAFS). The spectra show that cerium is in trivalent state. On the other hand, EXAFS result is well explained by the proposed structure model with the honeycomb arrangement.
crystals高取 沙悠理*; Pimon, M.*; Pollitt, S.*; Bartokos, M.*; Beeks, K.*; Gr
neis, A.*; 平木 貴宏*; 本間 徹生*; Hosseini, N.*; Leitner, A.*; et al.
New Journal of Physics (Internet), 27(4), p.043024_1 - 043024_10, 2025/04
被引用回数：4 パーセンタイル：71.44(Physics, Multidisciplinary)フッ化カルシウム単結晶中の低エネルギートリウム-229(
Th)核異性体のレーザー励起に関する最近の報告は、この系が原子核時計の有望な候補であることを示している。しかし、ドープされたTh周辺の微視的なイオン配列とその電子状態は実験的に調べられていない。Th周辺のイオン配列と電子状態は、原子核時計の遷移を正確に制御し、その性能を評価するために極めて重要である。本研究では、Th:CaFのX線吸収微細構造分光を用いて、ドープされたThの電荷状態と配位環境を調べた。その結果、ThはCaイオンの置換サイトに4+価でドープされており、Thに隣接する格子間サイトにある2個のF
イオンによって電荷が補償されていることがわかった。
田中 裕久*; 松村 大樹; 他9名*
SAE Technical Paper 2025-01-8474 (Internet), 8 Pages, 2025/04
On-board diagnosis (OBD) of gasoline vehicle emissions is detected by measuring the fluctuations of the rear oxygen sensor due to the time-dependent deterioration of the oxygen storage capacity (OSC) contained in the automotive catalyst materials. To detect OBD in various driving modes of automobiles with an order of magnitude higher accuracy than before, it is essential to understand the OSC mechanism based on fundamental science. In this study, time-resolved dispersive X-ray absorption fine structure (DXAFS) using synchrotron radiation was used to carry out a detailed analysis not only of the OSC of ceria-based complex oxides, which had previously been roughly understood, but also of how differences in design parameters such as the type of precious metals, reducing gases (CO and H), detection temperatures, and mileages (degree of deteriorations) affect the OSC rate in a fluctuating redox atmosphere. A fundamental characteristic was clearly demonstrated in ceria-based complex oxides: the oxygen release rate accompanying the generation of oxygen vacancies is overwhelmingly slower than the oxygen storage rate that restores the crystal structure. Another interesting result was revealed: when precious metals are supported, a competitive reaction occurs between the precious metal and the ceria-based complex oxide in the release/storage of oxygen, and the change in cerium valence from tetravalent to trivalent actually slows down. Furthermore, it was proven that CZY is more durable than CZ in terms of both OSC rate and amount. In this way, the basic scientific properties of ceria-based complex oxides, which are necessary for designing OBD logic, have been clarified.
濱田 翔太*; 松村 大樹; 他10名*
SAE Technical Paper 2025-01-8476 (Internet), 6 Pages, 2025/04
In order to comply with the tightening of global regulations on automobile exhaust gas, further improvements to exhaust gas control catalysts and upgrades to on-board diagnostics (OBD) systems must be made. Currently, oxygen storage capacity (OSC) is monitored by front and rear sensors before and after the catalyst, and deterioration is judged by a decrease in OSC, but it is possible that catalyst deterioration may cause the rear sensor to detect gas that has not been sufficiently purified. It is important to observe the activity changes when the catalyst deteriorates in more detail and to gain a deeper understanding of the catalyst mechanism in order to create guidelines for future catalyst development. In this study, we used a -TG (micro thermogravimetric balance) to analyze in detail how differences in design parameters such as the type of precious metal, detection temperature, and mileage (degree of deterioration) affect the OSC rate in addition to the OSC of the ceria-based composite oxide of the entire catalyst. It was found that CZY has better durability in terms of both OSC rate and amount than CZ. Furthermore, by comparing the results of experiments using time-resolved dispersive X-ray absorption fine structure (DXAFS) using synchrotron radiation, the reduction behavior of ceria was analyzed in more detail.
蓬田 匠; 高橋 嘉夫*
地球化学, 59(1), p.1 - 10, 2025/03
X線吸収微細構造(XAFS)分光法は、元素の価数や局所構造の情報を与える上に、殆どの元素に応用可能で元素選択性が高く、高感度な分析が可能であるため、天然試料中の主要および微量元素の化学種解析や天然模擬系での化学反応素過程の研究に広く応用されており、宇宙地球化学や環境化学では必須な手法になっている。本稿では、蛍光X線を高いエネルギー分解能で分析してXAFSを測定することで従来検出の難しかった元素を調べた事例や、新しい化学種についての情報を得た事例など、近年のXAFSを用いた研究例を紹介する。
