2025/03/19 更新

写真a

ワタナベ ヨシヒデ
渡邊 佳英
Yoshihide Watanabe
所属
客員教員部門 環境化学研究室 連携客員教授   
学位
博士(工学) ( 2005年9月   東京大学 )
外部リンク
連絡先
メールアドレス

研究分野

  • ものづくり技術(機械・電気電子・化学工学) / 触媒プロセス、資源化学プロセス

  • ナノテク・材料 / 薄膜、表面界面物性

  • 環境・農学 / 環境負荷低減技術、保全修復技術  / 環境化学

  • ナノテク・材料 / 分析化学

  • ナノテク・材料 / ナノマイクロシステム

主な研究論文

  • CO oxidation activity of non-reducible oxide-supported mass-selected few-atom Pt single-clusters

    A. Beniya, S. Higashi, N. Ohba, R. Jinnouchi, H. Hirata, Y. Watanabe

    Nature Communications   11(1)   1888   2020年4月

    Synergistic Promotion of NO-CO Reaction Cycle by Gold and Nickel Elucidated using Well-Defined Model Bimetallic Catalyst Surface

    A. Beniya, Y. Ikuta, N. Isomura, H. Hirata, Y. Watanabe

    ACS Catalysis   7(2)   1369 - 1377   2017年1月6日

    Portable ultrahigh-vacuum sample storage system for polarization-dependent total-reflection fluorescence X-ray absorption fine structure spectroscopy

    Y. Watanabe, Nishimura Yusaku F, Suzuki Ryo, Uehara Hiromitsu, Nimura Tomoyuki, Beniya Atsushi, Isomura Noritake, Asakura Kiyotaka, Takakusagi Satoru

    Journal of Vacuum Science & Technology A   34(2-2)   023201   2016年

    Size-dependent catalytic activity and geometries of size-selected Pt clusters on TiO2(110) surfaces

    Y. Watanabe, X. Wu , H. Hirata, N. Isomura

    Catalysis Science & Technology   1(8)   1490   2011年

    Multinuclear NMR Studies on the Thermal Stability of SAPO-34

    Y. Watanabe, A. Koiwai, H. Takeuchi, S.A. Hyodo, S. Noda

    Journal of Catalysis   143(2)   430   1993年

経歴

  • 豊田工業大学   連携客員教授

    2019年9月 - 現在

  • 豊田中央研究所   -

    1987年4月 - 現在

学歴

  • 大阪大学   基礎工学研究科   物性物理工学

    1985年4月 - 1987年3月

      詳細

    国名: 日本国

  • 京都大学   理学部   物理学および化学

    1981年4月 - 1985年3月

      詳細

    国名: 日本国

所属学協会

  • 触媒学会

  • 米国真空学会

  • 日本表面真空学会

  • 日本化学会

委員歴

  • 表面科学会中部支部   幹事(企画幹事)  

    2024年4月 - 現在   

      詳細

    団体区分:学協会

  • 日本表面真空学会   理事  

    2022年5月 - 2024年5月   

  • 日本表面真空学会   中部支部長  

    2022年4月 - 2024年4月   

      詳細

    団体区分:学協会

  • 日本表面真空学会   支部幹事・副支部長  

    2018年4月 - 2022年3月   

      詳細

    団体区分:学協会

  • 真空学会   東海支部役員  

    2015年9月 - 2018年3月   

      詳細

    団体区分:学協会

  • 日本表面真空学会   編集委員  

    2012年5月 - 現在   

      詳細

    団体区分:学協会

  • 表面科学会中部支部   幹事(企画幹事)  

    2012年4月 - 2018年3月   

      詳細

    団体区分:学協会

▼全件表示

研究テーマ

  • 環境材料の構造相転移と物性

    渡邊 佳英

    2017年度 - 現在

     詳細

    環境問題に寄与する物質の構造相転移とそれに伴う物性変化の研究

    成果:

    2023年度
    VO2ナノ粒子の金属‐絶縁体転移を粒子1個ごとに観察することを分子科学研究所と共同で取り組み、観察に成功した。

  • フローリアクタを利用した環境浄化・エネルギー変換システムの創製

    渡邊 佳英

    2017年度 - 現在

     詳細

    フローリアクタ・フローケミストリを利用し、環境負荷低減に寄与する技術の創製します。ライフサイクル目線での環境浄化技術、触媒技術などの創製を通じて、地球環境を守るために貢献することを目指します。

    成果:

    2023年度
    フローリアクタの活用方法について、FLOWST研究会活動を通じて検討を実施した

論文

  • 規制反応場を活用した固体触媒研究の新展開 原子数が規定された金属クラスターの触媒特性 招待 査読

    渡邊佳英

    触媒   66 ( 2 )   80 - 86   2024年 (   ISSN:0559-8958 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:東京 : 触媒学会  

    その他リンク: https://ndlsearch.ndl.go.jp/books/R000000004-I033463389

  • Metastability in the Insulator–Metal Transition for Individual Vanadium Dioxide Nanoparticles 招待 査読

    Kazutaka Nishikawa, Jun Nishida, Masamichi Yoshimura, Keiichi Nakamoto, Takashi Kumagai, Yoshihide Watanabe

    The Journal of Physical Chemistry C   127 ( 33 )   16485 - 16495   2023年8月 (   ISSN:1932-7447   eISSN:1932-7455 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:American Chemical Society (ACS)  

    DOI: 10.1021/acs.jpcc.3c02151

  • Effect of surface modification by Ar+ion irradiation on thermal hysteresis of VO<inf>2</inf> 査読

    K. Nishikawa, S. Takakura, M. Nakatake, M. Yoshimura, Y. Watanabe

    Journal of Applied Physics   133 ( 4 )   2023年1月 (   ISSN:0021-8979   eISSN:1089-7550 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Vanadium dioxide (VO2) undergoes a metal-insulator phase transition at ∼70 °C. As this is a first-order phase transition, VO2 exhibits thermal hysteresis. The reflectivity and electrical resistivity of VO2 drastically change at insulator-to-metal (TIMT) and metal-to-insulator (TMIT) transition temperatures during heating and cooling, respectively. For smart glass and thermal memory applications employing VO2, the origin and control factor of thermal hysteresis must be investigated. Additional elemental doping and nano-structuring of VO2 affect the thermal hysteresis width. However, the factors determining TIMT and TMIT remain unclear. TIMT and TMIT can be modified by irradiating Ar+ on the surface of VO2 nanostructures with varying Ar+ irradiation doses (nAr+) at 1 keV. The temperature-dependent reflectivity against IR light is evaluated. For VO2, TIMT decreases with nAr+ = 3.9 × 1014 cm-2; TMIT increases with nAr+ > 3.9 × 1015 cm-2. Ar+ irradiation decreases the thermal hysteresis width. Because the expected penetration depth of Ar+ at 1 keV into the VO2 surface is <6 nm, the VO2 chemical state at the outermost surface is investigated using x-ray absorption spectroscopy with soft x-ray irradiation. The V L-edge peak energy decreases with increasing nAr+ . Ar+ irradiation reduces V only at the outermost surface state. TIMT is more sensitive than TMIT to the reduction of V. The reduction of only a small fraction at the surface affects the phase transition of the entire VO2. These results are beneficial for understanding the cause of thermal hysteresis width and improving the performance of devices using VO2.

    DOI: 10.1063/5.0132957

  • Phase transition behavior in nanostructured VO2 with M1, M2, and R phases observed via temperature-dependent XRD measurements 査読

    Kazutaka Nishikawa, Masamichi Yoshimura, Yoshihide Watanabe

    Journal of Vacuum Science & Technology A   40 ( 3 )   2022年5月 (   ISSN:0734-2101   eISSN:1520-8559 )

     詳細

    担当区分:最終著者, 責任著者   掲載種別:研究論文(学術雑誌)  

    Vanadium dioxide (VO2) exhibits a metal-insulator phase transition at approximately 70 °C. Two different crystal structures, M1 and M2 phases, in the insulating state have been reported. The M2 phase is expected to be a Mott insulator, whereas the M1 phase is expected to act as a band insulator. It is important to clarify the origin and transition properties of the M2 phase. In this study, we fabricated VO2 nanostructures via sputtering deposition and subsequent lamp annealing at various O2 pressures. Temperature-dependent XRD measurements revealed that the nanostructured VO2 exhibits the M2 phase in temperatures just before the phase transition from M1 to R (metal state) during the heating process. The ratio of V5+/(V4+ + V5+) in nanostructured VO2 was estimated from XPS results; an increase in this ratio resulted in the broadening of the temperature range of the M2 phase. Furthermore, in the cooling process, direct phase transitions from R to M1 were observed. Structural changes are likely to occur in different pathways during heating and cooling. Our findings should contribute to the identification of the phase transition mechanism and to the development of a Mott field-effect transistor that utilizes nanostructured VO2 in the M2 phase.

    DOI: 10.1116/6.0001705

  • X-ray photoelectron spectroscopy study of Pt-cluster-induced electronic-state change of CeO2(111) surfaces 査読

    Syed Mohammad Fakruddin Shahed, Atsushi Beniya, Hirohito Hirata, Yoshihide Watanabe

    Journal of Vacuum Science & Technology A   40 ( 1 )   013204 - 013204   2022年1月 (   ISSN:0734-2101   eISSN:1520-8559 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:American Vacuum Society  

    DOI: 10.1116/6.0001382

  • CO oxidation activity of non-reducible oxide-supported mass-selected few-atom Pt single-clusters. 査読

    Atsushi Beniya, Shougo Higashi, Nobuko Ohba, Ryosuke Jinnouchi, Hirohito Hirata, Yoshihide Watanabe

    Nature communications   11 ( 1 )   1888 - 1888   2020年4月 (   ISSN:2041-1723 )

     詳細

    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Platinum nanocatalysts play critical roles in CO oxidation, an important catalytic conversion process. As the catalyst size decreases, the influence of the support material on catalysis increases which can alter the chemical states of Pt atoms in contact with the support. Herein, we demonstrate that under-coordinated Pt atoms at the edges of the first cluster layer are rendered cationic by direct contact with the Al2O3 support, which affects the overall CO oxidation activity. The ratio of neutral to cationic Pt atoms in the Pt nanocluster is strongly correlated with the CO oxidation activity, but no correlation exists with the total surface area of surface-exposed Pt atoms. The low oxygen affinity of cationic Pt atoms explains this counterintuitive result. Using this relationship and our modified bond-additivity method, which only requires the catalyst-support bond energy as input, we successfully predict the CO oxidation activities of various sized Pt clusters on TiO2.

    DOI: 10.1038/s41467-020-15850-4

  • Electrochemical Observation of High Oxophilicity and its Effect on Oxygen Reduction Reaction Activity of Au Clusters Mass-Selectively Deposited on Glassy Carbon 査読

    Kensaku Kodama, Atsushi Beniya, Noritake Isomura, Yoshihide Watanabe

    Electrocatalysis   9 ( 4 )   471 - 479   2018年7月 (   ISSN:1868-5994 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer New York LLC  

    The measurement procedure of oxophilicity and electrocatalytic activity for oxygen reduction reaction (ORR) on size-selected Au clusters was developed and applied. Mass-selected Au9 clusters were deposited on a glassy carbon substrate under ultrahigh vacuum (UHV) conditions, and the model electrode was transferred to an electrochemical cell with the rotating disk electrode (RDE) configuration. Cyclic voltammetry exhibited a significantly lower oxide-reduction peak potential of the Au clusters than that of bulk Au in the first cycle, thus confirming the exceptionally higher oxophilicities for the former. After performing cyclic voltammetry with an upper limit potential of 1.8 V versus a reversible hydrogen electrode, the ORR activity of the Au clusters was lower than that of bulk Au and bulk Pt. This result was partially ascribed to aggregations of Au clusters during the potential cycles. [Figure not available: see fulltext.].

    DOI: 10.1007/s12678-018-0464-4

  • Morphology of size-selected Ptn clusters on CeO2(111) 査読

    Syed Mohammad Fakruddin Shahed, Atsushi Beniya, Hirohito Hirata, Yoshihide Watanabe

    Journal of Chemical Physics   148 ( 11 )   114702 - 114709   2018年3月 (   ISSN:0021-9606 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:American Institute of Physics Inc.  

    Supported Pt catalysts and ceria are well known for their application in automotive exhaust catalysts. Size-selected Pt clusters supported on a CeO2(111) surface exhibit distinct physical and chemical properties. We investigated the morphology of the size-selected Ptn (n = 5-13) clusters on a CeO2(111) surface using scanning tunneling microscopy at room temperature. Ptn clusters prefer a two-dimensional morphology for n = 5 and a three-dimensional (3D) morphology for n ≥ 6. We further observed the preference for a 3D tri-layer structure when n ≥ 10. For each cluster size, we quantitatively estimated the relative fraction of the clusters for each type of morphology. Size-dependent morphology of the Ptn clusters on the CeO2(111) surface was attributed to the Pt-Pt interaction in the cluster and the Pt-O interaction between the cluster and CeO2(111) surface. The results obtained herein provide a clear understanding of the size-dependent morphology of the Ptn clusters on a CeO2(111) surface.

    DOI: 10.1063/1.5017906

  • Synergistic Promotion of NO-CO Reaction Cycle by Gold and Nickel Elucidated using a Well-Defined Model Bimetallic Catalyst Surface 査読

    Atsushi Beniya, Yasuhiro Ikuta, Noritake Isomura, Hirohito Hirata, Yoshihide Watanabe

    ACS CATALYSIS   7 ( 2 )   1369 - 1377   2017年2月 (   ISSN:2155-5435 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    A bimetallic catalyst of Au and Ni significantly increased the catalytic activity of the NO-CO reaction in comparison to monometallic Au and Ni catalysts. Unraveling the roles of Au and Ni atoms in the each of the NO-CO reaction steps occurring on the Au-Ni catalyst surface is crucial to reveal the origin of the increased activity. For this purpose, a well-defined Au/Ni(111) model catalyst was prepared, on which CO and NO adsorption, their coadsorption, NO dissociation, CO2 formation, and N-2 formation were investigated using infrared reflection absorption spectroscopy, temperature-programmed desorption/reaction, and density functional theory calculations. In the reaction process, the catalyst surface would be dominantly covered by N and O atoms, which would be removed from the surface by N-2 formation and CO2 formation. O atoms preferentially occupy the Ni hollow sites by segregating N atoms to the adsorption sites made up of Au and Ni atoms. Thus, only the N-2 formation step was affected by the Au atoms. The activation energy for the N-2 formation step, which was assigned as a rate-limiting step, was significantly lowered by the Au atoms, and this effect will contribute to the decrease of the activation energy of the overall NO-CO reaction. These results suggest that, by utilizing the adsorption site preferences among the coadsorbates on the bimetallic surface, the activation energy of a rate-limiting step would be significantly decreased; this could be useful in the development of advanced NOx reduction catalysts.

    DOI: 10.1021/acscatal.6b02714

  • Portable ultrahigh-vacuum sample storage system for polarization-dependent total-reflection fluorescence x-ray absorption fine structure spectroscopy 査読

    Yoshihide Watanabe, Yusaku F. Nishimura, Ryo Suzuki, Hiromitsu Uehara, Tomoyuki Nimura, Atsushi Beniya, Noritake Isomura, Kiyotaka Asakura, Satoru Takakusagi

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A   34 ( 2 )   023201 - 023205   2016年3月 (   ISSN:0734-2101   eISSN:1520-8559 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:A V S AMER INST PHYSICS  

    A portable ultrahigh-vacuum sample storage system was designed and built to investigate the detailed geometric structures of mass-selected metal clusters on oxide substrates by polarization-dependent total-reflection fluorescence x-ray absorption fine structure spectroscopy (PTRF-XAFS). This ultrahigh-vacuum (UHV) sample storage system provides the handover of samples between two different sample manipulating systems. The sample storage system is adaptable for public transportation, facilitating experiments using air-sensitive samples in synchrotron radiation or other quantum beam facilities. The samples were transferred by the developed portable UHV transfer system via a public transportation at a distance over 400 km. The performance of the transfer system was demonstrated by a successful PTRF-XAFS study of Pt-4 clusters deposited on a TiO2(110) surface. (C) 2015 American Vacuum Society.

    DOI: 10.1116/1.4936344

  • Atomically precise cluster catalysis towards quantum controlled catalysts 招待 査読

    Yoshihide Watanabe

    SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS   15 ( 6 )   WEB ONLY 063501   2014年12月 (   ISSN:1468-6996 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:NATL INST MATERIALS SCIENCE  

    Catalysis of atomically precise clusters supported on a substrate is reviewed in relation to the type of reactions. The catalytic activity of supported clusters has generally been discussed in terms of electronic structure. Several lines of evidence have indicated that the electronic structure of clusters and the geometry of clusters on a support, including the accompanying clustersupport interaction, are strongly correlated with catalytic activity. The electronic states of small clusters would be easily affected by cluster-support interactions. Several studies have suggested that it is possible to tune the electronic structure through atomic control of the cluster size. It is promising to tune not only the number of cluster atoms, but also the hybridization between the electronic states of the adsorbed reactant molecules and clusters in order to realize a quantumcontrolled catalyst.

    DOI: 10.1088/1468-6996/15/6/063501

  • Morphology and chemical states of size-selected Pt-n clusters on an aluminium oxide film on NiAl(110) 査読

    Atsushi Beniya, Noritake Isomura, Hirohito Hirata, Yoshihide Watanabe

    PHYSICAL CHEMISTRY CHEMICAL PHYSICS   16 ( 48 )   26485 - 26492   2014年 (   ISSN:1463-9076   eISSN:1463-9084 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    The adsorption states of size-selected Pt-n clusters (7 &lt;= n &lt;= 20) soft-landed on an Al2O3/NiAl(110) substrate were investigated using scanning tunneling microscopy, infrared reflection absorption spectroscopy, and temperature programmed desorption. Pt-n clusters lay flat on the surface with a planar structure (n &lt;= 18), and three-dimensional two-layer clusters start to appear at n &gt;= 19. By considering the Pt-Pt and Pt-oxide bonds in the cluster, the morphological transition could be reasonably explained. Using CO probe molecules, the chemical states of the Pt atoms inside the clusters were investigated. Two ontop CO species were observed inside the clusters, and were assigned as adsorbed CO on neutral and slightly cationic Pt atoms. Despite the first layer Pt atoms, the Pt-n clusters are composed of two kinds of Pt atoms. The observed size dependence of the Pt atoms inside the clusters may contribute to the size-dependent chemical reactivity of Pt-n clusters on the Al2O3 surface.

    DOI: 10.1039/c4cp01767f

  • Size-dependent catalytic activity and geometries of size-selected Pt clusters on TiO2(110) surfaces 査読

    Yoshihide Watanabe, Xingyang Wu, Hirohito Hirata, Noritake Isomura

    CATALYSIS SCIENCE & TECHNOLOGY   1 ( 8 )   1490 - 1495   2011年 (   ISSN:2044-4753   eISSN:2044-4761 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    Scanning tunneling microscope observations show a geometrical transition from a planar structure to a 3D structure at n = 8. This geometrical transition resulted in a significant decrease in the activation energy of the CO oxidation reaction. The upper-layer Pt atoms of the 3D cluster structure that starts to form at n = 8 are low-coordinated Pt atoms, and they may play an important role in the CO oxidation reaction.

    DOI: 10.1039/c1cy00204j

  • Development of a model for the lean NOx catalytic reaction with hydrocarbon adsorption and desorption 査読

    Y Watanabe, A Asano, T Kondo, Y Sakakibara, M Sugiura

    APPLIED CATALYSIS B-ENVIRONMENTAL   31 ( 3 )   221 - 228   2001年5月 (   ISSN:0926-3373 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    A numerical model for lean NOx catalytic reaction in consideration of hydrocarbon adsorption and desorption process, which is capable of predicting the performance of diesel lean NOx catalyst using diesel fuel as a supplemental reductant, has been developed. This model is based on our simplified kinetics for the adsorption and desorption of hydrocarbons, for the oxidation of hydrocarbons, and for the reduction of NOx by hydrocarbons including the desorbed one. The adsorption of diesel exhaust hydrocarbons was expressed by the Freundlich-type isotherm that has the adsorption equilibrium constant of exponential temperature dependence. The behavior of HC and NOx reactions and HC adsorption and desorption in diesel exhaust has been simulated successfully. (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0926-3373(00)00282-4

  • MULTINUCLEAR NMR-STUDIES ON THE THERMAL-STABILITY OF SAPO-34 査読

    Y WATANABE, A KOIWAI, H TAKEUCHI, SA HYODO, S NODA

    JOURNAL OF CATALYSIS   143 ( 2 )   430 - 436   1993年10月 (   ISSN:0021-9517 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS  

    DOI: 10.1006/jcat.1993.1287

  • AlveoMPU: Bridging the Gap in Lung Model Interactions Using a Novel Alveolar Bilayer Film 査読

    Minoru Hirano, Kosuke Iwata, Yuri Yamada, Yasuhiko Shinoda, Masateru Yamazaki, Sayaka Hino, Aya Ikeda, Akiko Shimizu, Shuhei Otsuka, Hiroyuki Nakagawa, Yoshihide Watanabe

    Polymers   16 ( 11 )   1486 - 1486   2024年5月 (     eISSN:2073-4360 )

     詳細

    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MDPI AG  

    The alveoli, critical sites for gas exchange in the lungs, comprise alveolar epithelial cells and pulmonary capillary endothelial cells. Traditional experimental models rely on porous polyethylene terephthalate or polycarbonate membranes, which restrict direct cell-to-cell contact. To address this limitation, we developed AlveoMPU, a new foam-based mortar-like polyurethane-formed alveolar model that facilitates direct cell–cell interactions. AlveoMPU features a unique anisotropic mortar-shaped configuration with larger pores at the top and smaller pores at the bottom, allowing the alveolar epithelial cells to gradually extend toward the bottom. The underside of the film is remarkably thin, enabling seeded pulmonary microvascular endothelial cells to interact with alveolar epithelial cells. Using AlveoMPU, it is possible to construct a bilayer structure mimicking the alveoli, potentially serving as a model that accurately simulates the actual alveoli. This innovative model can be utilized as a drug-screening tool for measuring transepithelial electrical resistance, assessing substance permeability, observing cytokine secretion during inflammation, and evaluating drug efficacy and pharmacokinetics.

    DOI: 10.3390/polym16111486

  • Phase transition behavior in nanostructured VO2 with M1, M2, and R phases observed via temperature-dependent XRD measurements 査読

    Kazutaka Nishikawa*, Masamichi Yoshimura, 渡邊 佳英

    Journal of Vacuum Science & Technology   40 ( 3 )   33401   2023年2月

     詳細

    担当区分:最終著者   掲載種別:研究論文(学術雑誌)   出版者・発行元:AIP publishing  

  • Effect of surface modification by Ar+ ion irradiation on thermal hysteresis of VO2 査読

    K. Nishikawa ; S. Takakura; M. Nakatake; M. Yoshimura; Y. Watanabe

    ( 133 )   045305   2023年1月

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: https://doi.org/10.1063/5.0132957

  • Insight for Designing Mass-Efficient Metal-Oxide-Supported Heterogeneous Catalyst from the Identification of the Catalytically Active Edge Sites Using Isotopically Labeled 13CO and 18O2 査読

    Atsushi Beniya, Kazutoshi Miwa, Hirohito Hirata, Yoshihide Watanabe, Shougo Higashi

    ACS Catalysis   12 ( 3 )   1977 - 1985   2022年1月 (   ISSN:2155-5435 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:American Chemical Society ({ACS})  

    Identifying the catalytically active sites and determining the reaction pathways on metal-oxide-supported few-atom clusters are of great importance for realizing mass-efficient heterogeneous catalysts. However, thermodynamics-based kinetic analyses, which are usually employed to elucidate such reaction mechanisms, can lead to contradictory conclusions even for simple catalytic systems such as CO oxidation. For CO oxidation on TiO2, a typical reducible oxide, the reaction is considered to proceed using the lattice O in the oxide. However, using isotopically labeled (CO)-C-13 and O-18(2), we herein show that only similar to 20% of the total CO2 is produced with the lattice O from TiO2; instead, most of the obtained CO2 is produced by O atoms from the introduced O-2 gas adsorbed on Pt atoms in the size-specific Pt clusters deposited on TiO2. We also show that both the introduced O-2 and lattice O react with CO adsorbed on hexa-coordinated Pt atoms at the edge of the Pt nanoclusters, suggesting that an edge structure that maximizes the coordination number of the edge Pt atoms could exhibit an improved catalytic activity.

    DOI: 10.1021/acscatal.1c03948

  • Growth of nanostructured VO2 via controlling oxidation of V thin films: Morphology and phase transition properties 査読

    Kazutaka Nishikawa*, Masamichi Yoshimura, 渡邊 佳英

    Journal of Applied Physics   129 ( 18 )   185303   2021年5月

     詳細

    担当区分:最終著者   掲載種別:研究論文(学術雑誌)  

  • Growth of nanostructured VO2 via controlling oxidation of V thin films: Morphology and phase transition properties 査読

    K. Nishikawa, M. Yoshimura, Y. Watanabe

    Journal of Applied Physics   129 ( 18 )   185303 - 185303   2021年5月 (   ISSN:0021-8979   eISSN:1089-7550 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AIP Publishing  

    Vanadium dioxide (VO2), which exhibits a metal-insulator phase transition at 70 °C, is known to alter its physical properties according to its surface morphology and fabrication process. The systematic investigation of a new fabrication method could not only clarify the origin of its phase transition but also advance progress in applications employing VO2 nanostructures. Here, we demonstrate the drastic enhancement of both the surface morphology and hysteresis of VO2 nanostructures composed of nanoparticles, by applying a sputtering deposition fabrication process, followed by lamp annealing. We investigated different growth conditions for VO2, especially using metallic precursor oxidation under a controlled pressure and temperature, and found that each growth condition led to different morphologies, nanoparticle sizes, and phase transition properties (hysteresis width). Despite a slight increase in particle diameter with annealing time and O2 pressure, the particle aggregation was found to substantially decrease. The temperature width of the hysteresis loop obtained by infrared light reflection measurements increased as the aggregation of VO2 nanoparticles decreased. During the cooling procedure, the transition of slightly aggregated VO2 nanoparticles was revealed to be a two-step process, with the lower transition temperature decreasing with an increase in particle isolation. Our results have the potential to elucidate the hysteresis-inducing mechanisms in VO2 and to aid the materialization of novel devices such as passive thermal control and thermal memory devices.

    DOI: 10.1063/5.0047985

  • Model reactions over size-selected clusters on oxide surfaces 査読

    Watanabe, Y.

    Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry   2018年

     詳細

    掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/B978-0-12-409547-2.12995-6

  • Catalysis of pt clusters on metal oxide 査読

    Watanabe, Y.

    Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry   2018年

     詳細

    掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/B978-0-12-409547-2.12983-X

  • Alumina-supported sub-nanometer Pt-10 clusters: amorphization and role of the support material in a highly active CO oxidation catalyst 査読

    Chunrong Yin, Fabio R. Negreiros, Giovanni Barcaro, Atsushi Beniya, Luca Sementa, Eric C. Tyo, Stephan Bartling, Karl-Heinz Meiwes-Broer, Sonke Seifert, Hirohito Hirata, Noritake Isomura, Sandeep Nigam, Chiranjib Majumder, Yoshihide Watanabe, Alessandro Fortunelli, Stefan Vajda

    JOURNAL OF MATERIALS CHEMISTRY A   5 ( 10 )   4923 - 4931   2017年3月 (   ISSN:2050-7488   eISSN:2050-7496 )

     詳細

    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    Catalytic CO oxidation is unveiled on size-selected Pt-10 clusters deposited on two very different ultrathin (approximate to 0.5-0.7 nm thick) alumina films: (i) a highly ordered alumina obtained under ultra-high vacuum (UHV) by oxidation of the NiAl(110) surface and (ii) amorphous alumina obtained by atomic layer deposition (ALD) on a silicon chip that is a close model of real-world supports. Notably, when exposed to realistic reaction conditions, the Pt-10/UHV-alumina system undergoes a morphological transition in both the clusters and the substrate, and becomes closely akin to Pt-10/ALD-alumina, thus reconciling UHV-type surface-science and real-world experiments. The Pt-10 clusters, thoroughly characterized via combined experimental techniques and theoretical analysis, exhibit among the highest CO oxidation activity per Pt atom reported for CO oxidation catalysts, due to the interplay of ultra-small size and support effects. A coherent interdisciplinary picture then emerges for this catalytic system.

    DOI: 10.1039/c6ta10989f

  • PTRF-XAFS Study of Size-Selected Pt7 Cluster Uniformly Deposited on an Al2O3/NiAl(110) Substrate by Lissajour Scanning

    NISHIMURA Yusaku F, BENIYA Atsushi, SUZUKI Ryo, ASAKURA Kiyotaka, TAKAKUSAGI Satoru, WATANABE Yoshihide

    KEK Progress Report (Web)   ( 2016-8 )   ROMBUNNO.144 (WEB ONLY)   2017年1月 (   ISSN:1344-6320 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Significant Transient Mobility of Platinum Clusters via a Hot Precursor State on the Alumina Surface 査読

    Atsushi Beniya, Hirohito Hirata, Yoshihide Watanabe

    JOURNAL OF PHYSICAL CHEMISTRY LETTERS   7 ( 22 )   4710 - 4715   2016年11月 (   ISSN:1948-7185 )

     詳細

    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Relaxation dynamics of hot metal clusters on oxide surfaces play a crucial role in a variety of physical and chemical processes. However, their transient mobility has not been investigated as much as other systems such as atoms and molecules on metal surfaces due to experimental difficulties. To study the role of the transient mobility of dusters on the oxide surface, we investigated the initial adsorption process of size-selected Pt clusters on a thin Al2O3 film. Soft-landing the size-selected clusters while suppressing the thermal migration resulted in the transient migration controlling the initial adsorption states as an isolated and aggregated duster, as revealed using scanning tunneling microscopy. We demonstrate that transient migration significantly contributes to the initial cluster adsorption process; the cross section for aggregation is seven times larger than the expected value from geometrical considerations, indicating that metal clusters are highly mobile during a energy dissipation process on the oxide surface.

    DOI: 10.1021/acs.jpclett.6b02362

  • Uniform deposition of size-selected clusters using Lissajous scanning 査読

    Beniya, Atsushi, Hirata, Hirohito, Watanabe, Yoshihide

    Journal of Vacuum Science & Technology A   34 ( 3 )   031601 - 031601   2016年 (   ISSN:0734-2101   eISSN:1520-8559 )

     詳細

    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:A V S AMER INST PHYSICS  

    Size-selected clusters can be deposited on the surface using size-selected cluster ion beams. However, because of the cross-sectional intensity distribution of the ion beam, it is difficult to define the coverage of the deposited clusters. The aggregation probability of the cluster depends on coverage, whereas cluster size on the surface depends on the position, despite the size-selected clusters are deposited. It is crucial, therefore, to deposit clusters uniformly on the surface. In this study, size-selected clusters were deposited uniformly on surfaces by scanning the cluster ions in the form of Lissajous pattern. Two sets of deflector electrodes set in orthogonal directions were placed in front of the sample surface. Triangular waves were applied to the electrodes with an irrational frequency ratio to ensure that the ion trajectory filled the sample surface. The advantages of this method are simplicity and low cost of setup compared with raster scanning method. The authors further investigated CO adsorption on size-selected Pt-n(n = 7, 15, 20) clusters uniformly deposited on the Al2O3/NiAl(110) surface and demonstrated the importance of uniform deposition. (C) 2016 American Vacuum Society.

    DOI: 10.1116/1.4944051

  • RHEED patterns calculated for Pt nano clusters on TiO&lt;inf&gt;2&lt;/inf&gt;(110) substrate 査読

    Yoshimi Horio, Yoshihide Watanabe, Yuji Takakuwa, Shuichi Ogawa

    e-Journal of Surface Science and Nanotechnology   13   125 - 128   2015年 (   ISSN:1348-0391 )

     詳細

    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:Surface Science Society of Japan  

    Platinum nano clusters, which are attractive material for highly activated catalysis, are usually evaluated by scanning tunneling microscopy (STM). Here we challenge to evaluate the structure of Pt nano clusters by reflection high-energy electron diffraction (RHEED) for the first time. The nano cluster models are made of n = 7 and n = 15 Pt atoms, which are deposited on TiO2 (110) substrate. The former has two dimensional (planer) and the latter three dimensional (two layer's) shapes. They are rotated around their [111] axes of Pt crystal, whose axes are also inclined from the substrate surface normal because of the atomically rough substrate surface. The RHEED patterns have been calculated by kinematic diffraction theory. From the calculated patterns for the two types of the clusters (n = 7 and 15), it is found that there is characteristic difference in the radial intensity distributions. The difference is attributed to existence or absence of the higher order reflections which arise from two layers of Pt(111).

    DOI: 10.1380/ejssnt.2015.125

  • STM and XPS study of CeO2(111) reduction by atomic hydrogen 査読

    Syed Mohammad Fakruddin Shahed, Tomo Hasegawa, Yasuyuki Sainoo, Yoshihide Watanabe, Noritake Isomura, Atsushi Beniya, Hirohito Hirata, Tadahiro Komeda

    SURFACE SCIENCE   628   30 - 35   2014年10月 (   ISSN:0039-6028   eISSN:1879-2758 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Reduction of CeO2(111)/Ru(0001) surface by atomic hydrogen was investigated using scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). We observed the formation of oxygen vacancy trimers and hydroxyl trimers on the stoichiometric CeO2(111) surface when it was exposed to atomic hydrogen at room temperature. The reaction of an impinging hydrogen atom with a surface oxygen atom yields a hydroxyl species, which diffuse on the surface until stabilized by the formation of OH trimers. The hydrogen atoms were located at atop sites of the oxygen atoms in the topmost surface layer. A reaction between the hopping hydrogen atom and the hydroxyl species yields a water molecule, which is desorbed from the surface leaving an oxygen defect. The oxygen vacancies were also observed as a trimer of vacancies. XPS measurements showed an increase of a reduced Ce and hydroxyl species with an amount of exposed hydrogen atoms. The former was estimated by measuring the ratio of Ce3+/Ce4+ in the Ce 3d components. Our study shows the formation of hydroxyl trimer species in atomic scale upon atomic hydrogen exposure to CeO2(111) surface which could offer new catalytic activity. (C) 2014 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.susc.2014.05.008

  • Epitaxial growth of CeO2(111) film on Ru(0001): Scanning tunneling microscopy (STM) and x-ray photoemission spectroscopy (XPS) study 査読

    Tomo Hasegawa, Syed Mohammad Fakruddin Shahed, Yasuyuki Sainoo, Atsushi Beniya, Noritake Isomura, Yoshihide Watanabe, Tadahiro Komeda

    JOURNAL OF CHEMICAL PHYSICS   140 ( 4 )   044711-044711-6   2014年1月 (   ISSN:0021-9606   eISSN:1089-7690 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER INST PHYSICS  

    We formed an epitaxial film of CeO2(111) by sublimating Ce atoms on Ru(0001) surface kept at elevated temperature in an oxygen ambient. X-ray photoemission spectroscopy measurement revealed a decrease of Ce4+/Ce3+ ratio in a small temperature window of the growth temperature between 1070 and 1096 K, which corresponds to the reduction of the CeO2(111). Scanning tunneling microscope image showed that a film with a wide terrace and a sharp step edge was obtained when the film was grown at the temperatures close to the reduction temperature, and the terrace width observed on the sample grown at 1060 K was more than twice of that grown at 1040 K. On the surface grown above the reduction temperature, the surface with a wide terrace and a sharp step was confirmed, but small dots were also seen in the terrace part, which are considerably Ce atoms adsorbed at the oxygen vacancies on the reduced surface. This experiment demonstrated that it is required to use the substrate temperature close to the reduction temperature to obtain CeO2(111) with wide terrace width and sharp step edges. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.

    DOI: 10.1063/1.4849595

  • Displacement reaction of CO by NO on the Ni(111) surface 査読

    Atsushi Beniya, Noritake Isomura, Hirohito Hirata, Yoshihide Watanabe

    SURFACE SCIENCE   613   28 - 34   2013年7月 (   ISSN:0039-6028   eISSN:1879-2758 )

     詳細

    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Co-adsorption states and thermal stability of NO + CO on Ni(111) were investigated using infrared reflection absorption spectroscopy and temperature programed desorption. The mechanism for the displacement of CO by NO was clarified. Co-adsorbed NO induced hollow-to-ontop site-conversion of CO; NO molecules occupied hollow sites. Ontop and two hollow CO species were observed in the co-adsorbed phase. The ontop and lower frequency hollow CO were assigned to CO neighboring hollow NO; higher frequency hollow CO were assigned to CO forming those domain. The hollow-to-ontop site-conversion of CO occurred due to local interactions between CO and NO, which destabilized the CO by 0.5 eV. This destabilization afforded facile displacement of CO by NO at 300 K. (C) 2013 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.susc.2013.03.001

  • Lateral displacement in soft-landing process and electronic properties of size-selected Pt-7 clusters on the aluminum oxide film on NiAl(110) 査読

    Atsushi Beniya, Noritake Isomura, Hirohito Hirata, Yoshihide Watanabe

    CHEMICAL PHYSICS LETTERS   576   49 - 54   2013年6月 (   ISSN:0009-2614   eISSN:1873-4448 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Adsorption states of size-selected Pt7 clusters soft-landed on an Al2O3/NiAl(1 1 0) were investigated using scanning tunneling microscopy and spectroscopy at 300 K. Pt-7 clusters lay flat on the surface with a planar structure and were preferentially adsorbed on domain boundaries (DBs) of the Al2O3 film. Because the clusters are thermally immobile, adsorption to DBs is controlled by transient mobility on the surface. The mean lateral displacement by transient migration is estimated to be similar to 8 nm. Distinct conductivity resonances through unoccupied states of the Pt7 clusters were observed near 2 V. (C) 2013 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.cplett.2013.05.033

  • Low temperature adsorption and site-conversion process of CO on the Ni(111) surface 査読

    Atsushi Beniya, Noritake Isomura, Hirohito Hirata, Yoshihide Watanabe

    SURFACE SCIENCE   606 ( 23-24 )   1830 - 1836   2012年12月 (   ISSN:0039-6028 )

     詳細

    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Low-temperature (25 K) adsorption states and the site conversion of adsorbed CO between the ontop and the hollow sites on Ni(111) were studied by means of temperature programmed desorption and infrared reflection absorption spectroscopy. The activation energy and pre-exponential factor of desorption were estimated to be 1.2 eV and 2.6x10(13) s(-1), respectively, in the limit of zero coverage. At low coverage, CO molecules preferentially adsorbed at the hollow sites below 100 K. With increasing temperature, the ontop sites were also occupied. Using a van't Hoff plot, the enthalpy and the entropy differences between the hollow and ontop CO were estimated to be 36 meV and 0.043 meV K-1, respectively, and the vibrational entropy difference was estimated to be 0.085 meV K-1. The positive entropy difference was the result of the low-energy frustrated translational mode of the ontop CO, which was estimated to be 4.6 +/- 03 meV. With the harmonic approximation, the upper limit of the activation energy of site hopping from ontop sites to hollow sites was estimated to be 61 meV. In addition, it was suggested that the activation energy of hollow-to-hollow site hopping via a bridge site was less than 37 meV. (C) 2012 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.susc.2012.07.026

  • Atomic-level Analysis and Catalytic Activity of Size-selected Pt Clusters Deposited on TiO2(110)

    Watanabe, Yoshihide, Isomura, Noritake, Hirata, Hirohito, Wu, Xingyang

    R&D Review of Toyota CRDL   42 ( 1 )   WEB ONLY 51-62   2011年3月 (   ISSN:1347-9652 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Cluster size dependence of Pt core-level shifts for mass-selected Pt clusters on TiO2(110) surfaces 査読

    Noritake Isomura, Xingyang Wu, Hirohito Hirata, Yoshihide Watanabe

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A   28 ( 5 )   1141 - 1144   2010年9月 (   ISSN:0734-2101 )

     詳細

    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:A V S AMER INST PHYSICS  

    In order to examine cluster size dependence, mass-selected platinum clusters, Pt-n (n=2-5, 7, 8, 10, 15), were deposited on TiO2(110) surfaces at room temperature under soft landing conditions, and their core levels were investigated by x-ray photoelectron spectroscopy. Pt core-level shifts with cluster size are observed. The binding energies of Pt 4f(7/2) decrease steeply with increasing cluster size up to n=7 for Pt-n and decrease gradually for n &gt;= 8. This inflection point (n=8) agrees well with the cluster size at a geometric transition (planar-to-three-dimensional) seen with scanning tunneling microscopy (STM) [N. Isomura, X. Wu, and Y. Watanabe, J. Chem. Phys. 131, 164707 (2009)]. It was found that the core-level shifts of mass-selected Pt clusters deposited on TiO2 are closely correlated with cluster geometries determined directly by atomic-resolution STM imaging. (C) 2010 American Vacuum Society. [DOI: 10.1116/1.3467033]

    DOI: 10.1116/1.3467033

  • Atomic-resolution imaging of size-selected platinum clusters on TiO2(110) surfaces 査読

    Noritake Isomura, Xingyang Wu, Yoshihide Watanabe

    JOURNAL OF CHEMICAL PHYSICS   131 ( 16 )   164707   2009年10月 (   ISSN:0021-9606   eISSN:1089-7690 )

     詳細

    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER INST PHYSICS  

    Size-selected Pt-n (n=4, 7-10, 15) clusters were deposited on TiO2(110)-(1 x 1) surfaces and imaged at atomic resolution using an ultrahigh-vacuum scanning tunneling microscope with a carbon nanotube tip. Clusters smaller than Pt-7 lay flat on the surface with a planar structure and a planar-to-three-dimensional transition occurred at n=8 for Pt-n clusters on TiO2. However, both Pt-8 and Pt-9 had two types of geometric structures. The geometric structures depend strongly on the number of atoms in the deposited cluster possibly because of the differences in binding energies in different-sized clusters and different degrees of interaction with the surface. We obtained atomic-resolution images of size-selected clusters on surfaces for the first time, enabling the identification of atomic alignments in the clusters on the surface. (C) 2009 American Institute of Physics. [doi:10.1063/1.3251786]

    DOI: 10.1063/1.3251786

  • A new experimental setup for high-pressure catalytic activity measurements on surface deposited mass-selected Pt clusters 査読

    Yoshihide Watanabe, Noritake Isomura

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A   27 ( 5 )   1153 - 1158   2009年9月 (   ISSN:0734-2101   eISSN:1520-8559 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:A V S AMER INST PHYSICS  

    A new experimental setup to study catalytic and electronic properties of size-selected clusters on metal oxide substrates from the viewpoint of cluster-support interaction and to formulate a method for the development of heterogeneous catalysts such as automotive exhaust catalysts has been developed. The apparatus consists of a size-selected cluster source, a photoemission spectrometer, a scanning tunneling microscope (STM), and a high-pressure reaction cell. The high-pressure reaction cell measurements provided information on catalytic properties in conditions close to practical use. The authors investigated size-selected platinum clusters deposited on a TiO(2)(110) surface using a reaction cell and STM. Catalytic activity measurements showed that the catalytic activities have a cluster-size dependency.

    DOI: 10.1116/1.3179160

  • STM Study of Size-Selected Pt Clusters on TiO2(110) Surface 査読

    Watanabe, Yoshihide, Isomura, Noritake, Yoshimura, Masamichi

    GRI Symposium II on Cluster Science   2009年

     詳細

    掲載種別:研究論文(学術雑誌)  

  • Catalytic Properties of Mass-Selected Pt Clusters on TiO2(110) Surface 査読

    Isomura, Noritake, Watanabe, Yoshihide, Wu, Xingyang

    5th International Symposium on Surface and Nanotechnology(ISSS-5)   2008年

     詳細

    掲載種別:研究論文(学術雑誌)  

  • Reactions of nitrogen monoxide on cobalt cluster ions: Reaction enhancement by introduction of hydrogen 査読

    Tetsu Hanmura, Masahiko Ichihashi, Yoshihide Watanabe, Noritake Isomura, Tamotsu Kondow

    JOURNAL OF PHYSICAL CHEMISTRY A   111 ( 3 )   422 - 428   2007年1月 (   ISSN:1089-5639 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Absolute cross sections for NO chemisorption, NO decomposition, and cluster dissociation in the collision of a nitrogen monoxide molecule, NO, with cluster ions Co-n(+) and ConH+ (n = 2-5) were measured as a function of the cluster size, n, in a beam-gas geometry in a tandem mass spectrometer. Size dependency of the cross sections and the change of the cross sections by introduction of H to Co-n(+) (effect of H-introduction) are explained by a statistical model based on the RRK theory, with the aid of the energetics obtained by a DFT calculation. It was found that the reactions are governed by the energetics rather than dynamics. For instance, Co-3(+) does not react appreciably with NO because the reactions are endothermic, while Co3H+ does because the reaction becomes exothermic by the H-introduction.

    DOI: 10.1021/jp063273a

  • Catalytic Properties of Size-Selected Pt Clusters on TiO2(110) Surface 査読

    Watanabe, Yoshihide, Isomura, Noritake, Matsubara, Hiroyuki

    Symposium on Size Selected Clasters 2007   2007年

     詳細

    掲載種別:研究論文(学術雑誌)  

  • STM Study of Size-Selected Pt Clusters on TiO2(110) Surface 査読

    Watanabe, Yoshihide, Isomura, Noritake, Yoshimura, Masamichi

    15th International Colloquium on Scanning Probe Microscopy   2007年

     詳細

    掲載種別:研究論文(学術雑誌)  

  • A new optimizing technique of a diesel engine aftertreatment system using HC DeNo(x) catalyst 査読

    M Ueda, A Asano, T Kondo, Y Watanabe, T Fukuma, Y Harada

    JSAE REVIEW   24 ( 1 )   47 - 51   2003年1月 (   ISSN:0389-4304 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    A new method that optimizes a control map of hydrocarbon (HC) addition to diesel exhaust gas for HC type Selective Catalytic Reduction DeNO(x) catalyst system has been developed. This method comprises a numerical model and a new optimization technique. The numerical model is capable of predicting performance of HC DeNO(x) with diesel fuel as a supplemental reductant. The control map of HC addition was optimized with the evolutionary programming based on the evolution of living things. As a result, NOx conversion with the optimized control map was found to be greater by 21% than that with the conventional control on Japanese 10-15 mode. (C) 2003 Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0389-4304(02)00249-7

  • Optimization of diesel engine aftertreatment system with a model of hydrocarbon selective catalyst reduction (HC-SCR) and evolutionary programming 査読

    Ueda, M., Asano, A., Kondo, T., Watanabe, Y., Fukuma, T., Harada, Y.

    SAE Technical Papers   2002年

     詳細

    掲載種別:研究論文(学術雑誌)  

    DOI: 10.4271/2002-01-0954

  • Numerical analysis of hydrocarbon adsorption and desorption behavior on NOx selective reduction catalysts using supplemental hydrocarbon under diesel transient condition 査読

    Watanabe, Y., Ueda, M., Sugiura, M., Harada, Y.

    SAE Technical Papers   2002年

     詳細

    掲載種別:研究論文(学術雑誌)  

    DOI: 10.4271/2002-01-0953

  • Time-resolved time-of-flight mass spectrometry with molecular-pulse-probes for analysis of dynamic process in surface catalytic reactions in the millisecond range (I) 査読

    T Motohiro, Y Kizaki, Y Sakamoto, K Higuchi, Y Watanabe, S Noda

    APPLIED SURFACE SCIENCE   121   319 - 322   1997年11月 (   ISSN:0169-4332 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Possible future developments of new automobile catalysts undoubtedly utilize transient phenomena at the change of gas composition under the cooperative functions of the catalytic components: noble metal particles, supports and third additives including 'migration' of adsorbed species and their temporal 'storage'. To explore highly cooperative he ts of the catalytic components, a new tool to detect transient products from artificially designed small area samples in the ms range was developed, which is more robust and tolerant for dynamic changes of vacuum conditions than the conventional UHV surface science tools. (C) 1997 Elsevier Science B.V.

    DOI: 10.1016/S0169-4332(97)00315-2

  • CATALYTIC PROPERTIES OF THIN-FILMS BY SIMULTANEOUS OBLIQUE SPUTTER-DEPOSITION OF 2 MATERIALS FROM DIFFERENT DIRECTIONS 査読

    Y WATANABE, S HYODO, T MOTOHIRO, T HIOKI, M SUGIURA, S NODA

    THIN SOLID FILMS   256 ( 1-2 )   68 - 72   1995年2月 (   ISSN:0040-6090 )

     詳細

    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    Catalytic properties of simultaneously obliquely sputter-deposited platinum-metal oxide thin films were studied. We attempted to study the effect of combination of the metal oxide with platinum on the NO-CO reaction by minimizing differences in the particle size and the dispersion of platinum in the samples. Simultaneously obliquely sputter-deposited Pt-metal oxide thin film systems gave comparable particle sizes and dispersion of platinum in different combinations of several metal oxides with platinum. The catalytic property of platinum was changed by the choice of metal oxide. We found this simultaneous oblique sputter deposition to be an excellent technique for obtaining a model catalyst suitable for exploring the synergistic catalytic reaction and the role of promoters at the interfaces of different materials, which facilitates the survey of industrial catalysts.

    DOI: 10.1016/0040-6090(94)06279-X

  • THERMALLY-INDUCED STRUCTURAL MODIFICATION OF NANOMETER-ORDER MO-SI MULTILAYERS BY THE SPECTRAL REFLECTANCE OF LASER-PLASMA SOFT X-RAYS 査読

    H AZUMA, A TAKEICHI, KONOMI, I, Y WATANABE, S NODA

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS   32 ( 5A )   2078 - 2082   1993年5月 (   ISSN:0021-4922 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JAPAN J APPLIED PHYSICS  

    Thermally induced structural modification of a nm-order multilayer of Mo/Si was investigated by spectral reflectance of soft X-rays from laser-produced plasma. Dependence of reflectivity of the nm-order multilayers on the incidence angle of soft X-rays indicated that some structural changes start to occur at 300-degrees-C and that the nm-order multilayer structures shrink at 500-degrees-C because of the formation of Mo-silicide. These results were found to be consistent with the cross-sectional transmission electron microscope observations. It is clearly shown that measurement of spectral reflectance of soft X-rays from laser plasma is a powerful method for analyzing nm-order structural modifications of multilayers.

    DOI: 10.1143/JJAP.32.2078

  • SINGLE-SHOT MEASUREMENT OF SPECTRAL REFLECTANCE OF A SOFT-X-RAY MULTILAYER MIRROR USING A LASER-PLASMA X-RAY SOURCE 査読

    H AZUMA, Y WATANABE, Y KATO, T MOTOHIRO, S NODA, K MURAI

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   31 ( 2B )   L203 - L205   1992年2月 (   ISSN:0021-4922 )

     詳細

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JAPAN J APPLIED PHYSICS  

    We propose a new experimental arrangement to measure spectral reflectance of multilayer coatings in the soft X-ray region in a single laser shot, where laser-produced plasma is used as a light source. Reflectivity measurement of a Mo/Si multilayer having a 2d spacing of 24 nm is presented.

    DOI: 10.1143/JJAP.31.L203

  • 斜め蒸着膜のミクロ構造(III)

    渡邊 佳英, 竹田 康彦, 元廣 友美, 野田 正治

    粉体および粉末冶金   38 ( 3 )   345 - 347   1991年 (   ISSN:0532-8799 )

     詳細

    記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 粉体粉末冶金協会  

    Thin films were formed by simultaneous depositions from two AF-sputter sources which were mounted so that the incident angles of the sputtered particles were +70° and -70° from the substrate normal. A microstructure of ZnTe/SiO&lt;SUB&gt;2&lt;/SUB&gt; thin film were examined by TEM. The ZnTe/SiO&lt;SUB&gt;2&lt;/SUB&gt; thin film was an anisotropic nm-scale composite whose microstructure was similar to that of the film computer-generated with the simulated deposition conditions. A Cu/SiO&lt;SUB&gt;2&lt;/SUB&gt; thin film was also inferred to have an anisotrop ic microstructure through the observation of the polarization of the...

    DOI: 10.2497/jjspm.38.345

  • Nanometer-Scale Composite Structures Formed by Simultaneous Oblique Sputter-Deposition of Two Materials from Different Directions 査読

    Tomoyoshi Motohiro, Yasuhiko Takeda, Yoshihide Watanabe, Shoji Noda

    MRS Proceedings   206   1990年1月

     詳細

    掲載種別:研究論文(学術雑誌)   出版者・発行元:Cambridge University Press ({CUP})  

    DOI: 10.1557/proc-206-423

▼全件表示

MISC

  • 久しぶり現地開催の学術講演会@名古屋

    渡邊 佳英

    表面と真空   67 ( 7 )   309 - 309   2024年7月 (   ISSN:2433-5835   eISSN:2433-5843 )

     詳細

    記述言語:日本語   出版者・発行元:公益社団法人 日本表面真空学会  

    DOI: 10.1380/vss.67.309

  • 学術講演会JVSS2023開催報告

    渡邊 佳英

    表面と真空   67 ( 5 )   238 - 238   2024年5月 (   ISSN:2433-5835   eISSN:2433-5843 )

     詳細

    記述言語:日本語   出版者・発行元:公益社団法人 日本表面真空学会  

    DOI: 10.1380/vss.67.238

  • 中部支部主催 2023年度市民講座やさしい表面と真空の科学「折り紙の科学」開催報告

    渡邊 佳英

    表面と真空   66 ( 10 )   613 - 613   2023年10月 (   ISSN:2433-5835   eISSN:2433-5843 )

     詳細

    記述言語:日本語   出版者・発行元:公益社団法人 日本表面真空学会  

    DOI: 10.1380/vss.66.613

  • 2022年度 中部支部研究会『紫外・軟X線領域の放射光利用』開催報告

    渡邊 佳英

    表面と真空   66 ( 2 )   124 - 124   2023年2月 (   ISSN:2433-5835   eISSN:2433-5843 )

     詳細

    記述言語:日本語   出版者・発行元:公益社団法人 日本表面真空学会  

    DOI: 10.1380/vss.66.124

  • 特集「ものを隔てる膜の表面・真空科学」企画趣旨

    渡邊 佳英, 山下 良之

    表面と真空   64 ( 4 )   154 - 155   2021年 (   ISSN:2433-5835   eISSN:2433-5843 )

     詳細

    記述言語:日本語   出版者・発行元:公益社団法人 日本表面真空学会  

    DOI: 10.1380/vss.64.154

  • 中部支部主催 2018年度市民講座 やさしい表面と真空の科学「料理と科学」開催報告

    渡邊 佳英

    表面と真空   61 ( 12 )   805 - 805   2018年 (   ISSN:2433-5835 )

     詳細

    記述言語:日本語   出版者・発行元:公益社団法人 日本表面真空学会  

  • A new optimizing technique of a diesel engine aftertreatment system using HC DeNo(x) catalyst

    M Ueda, A Asano, T Kondo, Y Watanabe, T Fukuma, Y Harada

    JSAE REVIEW   24 ( 1 )   47 - 51   2003年1月 (   ISSN:0389-4304 )

     詳細

    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    A new method that optimizes a control map of hydrocarbon (HC) addition to diesel exhaust gas for HC type Selective Catalytic Reduction DeNO(x) catalyst system has been developed. This method comprises a numerical model and a new optimization technique. The numerical model is capable of predicting performance of HC DeNO(x) with diesel fuel as a supplemental reductant. The control map of HC addition was optimized with the evolutionary programming based on the evolution of living things. As a result, NOx conversion with the optimized control map was found to be greater by 21% than that with the conventional control on Japanese 10-15 mode. (C) 2003 Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0389-4304(02)00249-7

  • 選択還元型NOx触媒のシミュレーションと最適化(1)HC吸着を利用した選択還元型NOx触媒のモデリング

    渡邊 佳英

    豊田中央研究所R&Dレビュ-   37 ( 3 )   32 - 39   2002年9月 (   ISSN:0385-1508 )

     詳細

    記述言語:英語   出版者・発行元:豊田中央研究所  

  • Pt/Fe熱処理セピオライト触媒 (特集:排気浄化用触媒)

    坂野 幸次, 渡辺 佳英, 杉浦 正洽

    豊田中央研究所R&Dレビュ-   33 ( 3 )   13 - 21   1998年9月 (   ISSN:0385-1508 )

     詳細

    記述言語:日本語   出版者・発行元:豊田中央研究所  

  • 斜め蒸着膜のミクロ構造 III

    渡邊 佳英, 竹田 康彦, 元廣 友美, 野田 正治

    粉体および粉末冶金   38 ( 3 )   345 - 347   1991年 (   ISSN:0532-8799 )

     詳細

    記述言語:日本語   出版者・発行元:Japan Society of Powder and Powder Metallurgy  

    Thin films were formed by simultaneous depositions from two AF-sputter sources which were mounted so that the incident angles of the sputtered particles were +70° and -70° from the substrate normal. A microstructure of ZnTe/SiO2 thin film were examined by TEM. The ZnTe/SiO2 thin film was an anisotropic nm-scale composite whose microstructure was similar to that of the film computer-generated with the simulated deposition conditions. A Cu/SiO2 thin film was also inferred to have an anisotrop ic microstructure through the observation of the polarization of the transmitted light. Simultaneous oblique depositions from two sources will be a promising method to generate unique sans composites.

    DOI: 10.2497/jjspm.38.345

    その他リンク: https://jlc.jst.go.jp/DN/JALC/00008562395?from=CiNii

▼全件表示

書籍等出版物

  • Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry

    渡邊佳英( 担当: 分担執筆 ,  範囲: Model Reactions Over Size-Selected Clusters on Oxide Surfaces)

    Elsevier  2017年 

     詳細

    著書種別:学術書

講演・口頭発表等

  • Metastability in the Insulator-Metal Transition for Individual VO2 Nanoparticles 国際会議

    K. Nishikawa, J. Nishida, T. Kumagai, Y. Watanabe

    NanospecFY2023  ( Okazaki Conference Center )   2024年3月 

     詳細

    開催年月日: 2024年3月

    会議種別:ポスター発表  

  • Thermal Hysteresis Loop in IR Reflectivity of Nanostructured Phase-Change-Material VO2 Presentation 国際会議

    Kazutaka Nishikawa*, Masamichi Yoshimura, Yoshihide Watanabe

    MRS Fall Meeting 2021  ( Boston,USA )   2021年12月  Materials Research Society

     詳細

    会議種別:口頭発表(一般)  

  • Morphology of nanostructured VO2 films fabricated by sputtering and annealing process 国際会議

    Kazutaka Nishikawa*, Masamichi Yoshimura, Yoshihide Watanabe

    9th International Symposium on Surface Science (ISSS-9)  ( Online )   2021年11月  The Japan Society of Vacuum and Surface Science

     詳細

    会議種別:口頭発表(一般)  

  • 酸化物表面上における質量選別Ptクラスタの構造とCO酸化反応 招待 国際会議

    渡邊 佳英, 紅谷 篤史**, S. M. F. Shahed**

    日本表面真空学会学術講演会  ( つくば )   2019年10月 

     詳細

    会議種別:口頭発表(招待・特別)  

  • Cluster-support interactions control the morphological transitions and 招待 国際会議

    Yoshihide Watanabe, Syed Mohammad, Fakruddin Shahed, Hirohito Hirata, Atsushi Beniya

    Cluster Surface Interaction Workshop 2018  ( Clarion Hotel & Congress Trondheim )   2018年6月 

     詳細

    開催年月日: 2018年6月

    記述言語:英語   会議種別:口頭発表(招待・特別)  

  • 酸化物上2次元Ptクラスタと3次元Ptクラスタの構造転移と触媒特性 招待

    渡邊佳英

    次世代デバイス実現に向けた先端二次元物質の物理と化学  ( 科学技術交流財団研究交流センター, 名古屋 )   2016年10月  公益財団法人科学技術交流財団

     詳細

    記述言語:日本語   会議種別:口頭発表(招待・特別)  

▼全件表示

受賞

  • AVS Shop Notes prize for 2016

    2017年6月   AVS(American Vacuum Society)  

    渡邊佳英

     詳細

    “Portable ultrahigh-vacuum sample storage system for polarization-dependent total-reflection fluorescence x-ray absorption fine structure spectroscopy,” J. Vac. Sci. Technol. A 34 (2), 023201 (2016)が対象論文
    Yoshihide Watanabe, Yusaku F. Nishimura, Ryo Suzuki, Hiromitsu Uehara, Tomoyuki Nimura, Atsushi Beniya, Noritake Isomura, Kiyotaka Asakura and Satoru Takakusagi

  • AVS Shop Notes prize for 2016

    2016年   American Vacuum Society  

その他研究活動

  • 朝日遺跡サポーター

    2018年 - 現在

担当科目(学外)

  • 大学院工学専攻特別講義B

    2020年12月 - 2021年1月 機関名:名古屋工業大学

  • ナノ材料評価学特論Ⅰ(一部)

    2019年6月 - 2023年5月 機関名:名古屋工業大学

出版した教科書・参考書

  • Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry

    2018年  Catalysis of Pt Clusters on Metal Oxide 

    著作編者:Klaus Wandelt  出版社:Elsevier

  • Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry

    2017年  Model Reactions Over Size-Selected Clusters on Oxide Surfaces 

    著作編者:Klaus Wandelt  出版社:Elsevier

社会貢献活動

  • 清須マイスター

    役割:助言・指導, 運営参加・支援

    2017年 - 現在

     詳細

    種別:その他