水の酸化の超高効率化を目指した超分子錯体触媒の創製

• Project Area: Chemical conversion of solar energy by artificial photosynthesis: a breakthrough by fusion of related fields toward realization of practical processes
• Project/Area Number: 25107526
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Institute for Molecular Science
• Principal Investigator: 正岡 重行 分子科学研究所, 生命・錯体分子科学研究領域, 准教授 (20404048)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2014: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: 金属錯体 / 酸素発生

Outline of Annual Research Achievements

酸素発生触媒の開発は、人工光合成における最重要課題の一つである。本研究では、生体内酵素の多電子移動中心に着想を得た設計指針に基づき、多核金属錯体を対象とする酸素発生触媒開発を進めた。具体的には、これまでの研究により高い酸素発生触媒能を有することがわかっている超分子鉄五核錯体を基盤として、金属イオンを入れ替えたり配位子に化学修飾を施すなどして、その電子構造を詳細にチューニングし、高機能（低過電圧・高活性）触媒が創出できる可能性を検討した。
具体的には、鉄五核錯体の１つまたは２つを別の遷移金属イオンに入れ替えた異種金属五核錯体を合成し、その電気化学的挙動を調べた。その結果、鉄五核錯体に於いて観測されていた５段階の可逆な酸化還元波のうち、１つまたは２つだけが選択的にシフトし、異種金属を導入する戦略により、五核錯体の電子構造を詳細にチューニングできることがわかった。更に、異種金属の部分的な導入により、同一種五核錯体に比べて酸素発生電位が異なることがわかった。この結果は、適した導入金属イオンを選択することにより、酸素発生過電圧を低下できることを意味している。また、配位子部位の化学修飾によっても、当該多核金属錯体の酸化還元特性をチューニングできることがわかった。一例としては、プロトン共役電子移動サイトを導入した多座配位子を用いて合成された鉄五核錯体では、酸素発生電位をpHに依存させることに成功した。

Research Progress Status

26年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

26年度が最終年度であるため、記入しない。

Research Products

• [Journal Article] Design of Mononuclear Ruthenium Catalysts for Low-Overpotential Water Oxidation (2015)
  • Author(s): Masaya Okamura and Shigeyuki Masaoka
  • Journal Title: Chem. Asian J. Volume: 10 Issue: 2 Pages: 306-315
  • DOI: 10.1002/asia.201402781
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Influence of ligand flexibility on the electronic structure of oxidized Ni(III)-phenoxide complexes (2014)
  • Author(s): M. Kawai, T. Yamaguchi, S. Masaoka, F. Tani, T. Kohzuma, L. Chiang, T. Storr, K. Mieda, T. Ogura, r. K. Szilagyi, and Y. Shimazaki
  • Journal Title: Inorganic Chemistry Volume: 53 Issue: 19 Pages: 10195-10202
  • DOI: 10.1021/ic501181k
  • Peer Reviewed
• [Journal Article] Three Distinct Redox States of an Oxo-Bridged Dinuclear Ruthenium Complex (2014)
  • Author(s): Masaki Yoshida, Mio Kondo, Toshikazu Nakamura, Ken Sakai, and Shigeyuki Masaoka
  • Journal Title: Angewandte Chemie International Edition Volume: 53 Issue: 43 Pages: 11519-11523
  • DOI: 10.1002/anie.201406443
  • Peer Reviewed
• [Journal Article] Electrochemical Behavior of Phosphine-Substituted Ruthenium(II) Polypyridine Complexes with a Single Labile Ligand (2014)
  • Author(s): Go Nakamura, Masaya Okamura, Masaki Yoshida, Takayoshi Suzuki, Hideo D. Takagi, Mio Kondo, and Shigeyuki Masaoka
  • Journal Title: Inorg. Chem. Volume: 53 Issue: 14 Pages: 7214-7226
  • DOI: 10.1021/ic5003644
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Electrochemical response of metal complexes in homogeneous solution under photoirradiation (2014)
  • Author(s): Arisa Fukatsu, Mio Kondo, Masaya Okamura, Masaki Yoshida, and Shigeyuki Masaoka
  • Journal Title: Sci. Rep. Volume: 4 Issue: 1 Pages: 5327-5327
  • DOI: 10.1038/srep05327
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Tuning of Metal-Metal Interactions in Mixed-Valence States of Cyclometalated Dinuclear Ruthenium and Osmium Complexes Bearing Tetrapyridylpyrazine or -benzene (2014)
  • Author(s): Takumi Nagashima, Takuya Nakabayashi, Takashi Suzuki, Katsuhiko Kanaizuka, Hiroaki Ozawa, Yu-Wu Zhong, Shigeyuki Masaoka, Ken Sakai and Masa-aki Haga
  • Journal Title: Organometallics Volume: 33 Issue: 18 Pages: 4893-4904
  • DOI: 10.1021/om500142t
  • Peer Reviewed
• [Journal Article] 金属錯体を触媒とする水の酸化反応 (2014)
  • Author(s): 正岡重行
  • Journal Title: 化学工業 Volume: 65 Pages: 194-199
• [Journal Article] Arene-perfluoroarene Interactions for Crystal Engineering of Metal Complexes: Controlled Self-assembly of Paddle-wheel Dimers (2013)
  • Author(s): Takahiro Itoh, Mio Kondo, Mari Kanaike, and Shigeyuki Masaoka
  • Journal Title: CrystEngComm Volume: 15 Issue: 31 Pages: 6122-6126
  • DOI: 10.1039/c3ce40777b
  • Peer Reviewed
• [Journal Article] Dispersed Ru Nanoclusters Transformed from A Grafted Trinuclear Ru Complex on SiO2 for Selective Alcohol Oxidation (2013)
  • Author(s): Satoshi Muratsugu, Min Hwee Lim, Takahiro Itoh, Wipavee Thumrongpatanaraks, Mio Kondo, Shigeyuki Masaoka, T. S. Andy Hor, Mizuki Tada
  • Journal Title: Dalton Transactions Volume: 42 Issue: 35 Pages: 12611-12619
  • DOI: 10.1039/c3dt51142a
  • Peer Reviewed
• [Journal Article] プロトン共役電子移動を示す有機配位子を導入した多電子移動錯体触媒 (2013)
  • Author(s): 岡村将也, 正岡重行
  • Journal Title: ペトロテック Volume: 36 Pages: 613-617
  • NAID: 40019782529
• [Presentation] Artificial Molecular Catalysts Designed for Water Oxidation (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: 8th International Symposium on Nanomedicine (ISNM2014)
  • Place of Presentation: Ehime University, Matsuyama, Ehime, Japan
  • Year and Date: 2014-12-04
  • Invited
• [Presentation] Molecular Catalysts Designed for Water Oxidation (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: 2014 International Conference on Artificial Photosynthesis (ICARP2014)
  • Place of Presentation: Awaji Yumebutai International Conference Center, Awaji, Hyogo, Japan
  • Year and Date: 2014-11-27
  • Invited
• [Presentation] Electrochemical evaluation of photochemical and catalytic properties of transition metal complexes (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: Annual Meeting on Photochemistry 2014
  • Place of Presentation: Hokkaido University, Sapporo, Hokkaido, Japan
  • Year and Date: 2014-10-11
  • Invited
• [Presentation] Molecular Catalysts Designed for Water Oxidation (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: 2nd Japan-UK Joint Symposium on Coordination Chemistry
  • Place of Presentation: Chuo University, Tokyo, Tokyo, Japan
  • Year and Date: 2014-09-17
  • Invited
• [Presentation] Water Oxidation Catalyzed by Mononuclear and Multinuclear Metal Complexes (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: Symposium on Molecular Catalysis Toward Sustainable Energy
  • Place of Presentation: Nanyang Technological University, Singapore, Singapore
  • Year and Date: 2014-07-26
  • Invited
• [Presentation] Water Oxidation Catalyzed by Mononuclear and Multinuclear Metal Complexes (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: 41st International Conference on Coordination Chemistry
  • Place of Presentation: Suntec Singapore Convention & Exhibition Centre, Singapore, Singapore
  • Year and Date: 2014-07-22
  • Invited
• [Presentation] Water Oxidation Catalyzed by Transition Metal Complexes (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: Supramolecular Coordination Chemistry, Japan-Canada Joint Symposium in CSC2014
  • Place of Presentation: Vancouver Convention Centre, Vancouver, Canada
  • Year and Date: 2014-06-04
  • Invited
• [Presentation] Water Oxidation Catalyzed by Transition Metal Complexes (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: Pure and Applied Chemistry International Conference (PACCON)
  • Place of Presentation: Centara Hotel and Convention Centre, Khon Kaen, Thailand
  • Invited
• [Presentation] Water Oxidation Catalyzed by Transition Metal Complexes (2014)
  • Author(s): Shigeyuki Masaoka
  • Organizer: Joint IMS-KU Workshop on Molecular Sciences towards Green Sustainability
  • Place of Presentation: Kasetsart University, Bangkok, Thailand
  • Invited
• [Presentation] Multi-electron transfer reactions catalyzed by transition metal complexes (2013)
  • Author(s): Shigeyuki Masaoka
  • Organizer: 63rd JSCC Symposium
  • Place of Presentation: University of the Ryukyus, Okinawa, Japan
  • Invited
• [Presentation] Water Oxidation Catalyzed by Artificial Transition Metal Complexes (2013)
  • Author(s): Shigeyuki Masaoka
  • Organizer: The 51st Annual Meeting of the Biophysical Society of Japan
  • Place of Presentation: Kyoto International Conference Center, Kyoto, Japan
  • Invited
• [Presentation] Water Oxidation Catalyzed by Metal Complexes (2013)
  • Author(s): Shigeyuki Masaoka
  • Organizer: International Symposium for the 70th anniversary of the Tohoku Branch of the Chemical Society of Japan
  • Place of Presentation: Tohoku University, Sendai, Japan
  • Invited
• [Presentation] Water Oxidation by Mono- and Multinuclear Metal Complexes (2013)
  • Author(s): Shigeyuki Masaoka
  • Organizer: IMS Asian International symposium: Japan-China Joint Coordination Chemistry Symposium for Young Scientists on Advanced Coordination Materials
  • Place of Presentation: Institute for Molecular Science, Okazaki, Japan
  • Invited
• [Presentation] Water Oxidation by Mononuclear and Multinuclear Metal Complexes: Mechanisms and a New Catalyst Design (2013)
  • Author(s): Shigeyuki Masaoka
  • Organizer: Water Oxidation by Mononuclear and Multinuclear Metal Complexes: Mechanisms and a New Catalyst Design
  • Place of Presentation: Kyushu University, Fukuoka, Japan
  • Invited
• [Book] 金属錯体を触媒とする水素および酸素発生反応「CSJカレントレビュー15 次世代のバイオ水素エネルギー」 (2014)
  • Author(s): 吉田将己, 正岡重行
  • Publisher: 化学同人
• [Book] 金属錯体を用いた水の酸化触媒の創製と人工光合成への挑戦「人工光合成 実用化に向けた最新技術」 (2013)
  • Author(s): 近藤美欧, 正岡重行
  • Publisher: 情報機構
• [Book] Cerium(IV) in an Acidic Solution: A ‘Non-Innocent’ Oxidantin Cerium: Molecular Structure, Technological Applications and Health Effects (2013)
  • Author(s): Masaki Yoshida and Shigeyuki Masaoka
  • Publisher: Nova Science Publishers, Inc.