Development of layered oxyhalide photocatalysts with "thick" fluorite layer

• Project/Area Number: 21K20556
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0502:Inorganic/coordination chemistry, analytical chemistry, inorganic materials chemistry, energy-related chemistry, and related fields
• Research Institution: Kyoto University
• Principal Investigator: Kato Daichi 京都大学, 工学研究科, 助教 (40906921)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000); Fiscal Year 2022: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2021: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: 光触媒 / 酸塩化物 / 複合アニオン / 複合アニオン化合物 / 酸ハロゲン化物 / バンド構造制御 / 蛍石ブロック

Outline of Research at the Start

本研究では、ダブル蛍石層に代わる新たなビルディングブロックとして拡張蛍石層(一般式[MsO2s-2])に着目し、これらの新しいビルディングブロックを有する酸ハロゲン化物光触媒の開発を目的とする。申請者がこれまで培った知見を活かして、蛍石層の拡張が電子状態や活性に与える影響を、実験・理論の両面から解明することで、高効率な光触媒の設計指針を確立する。

Outline of Final Research Achievements

The layered oxyhalide family has recently attracted much attention as candidates for highly efficient and stable water-splitting photocatalysts. Since their electronic states are dominated by double-fluorite layers such as Bi2O2, this study focused on the expansion of the fluorite layers (development of thicker fluorite layers) to design more efficient layered oxychloride photocatalyst. Representative research achievements include desingning photocatalytic properties of Bi2MO4Cl (M = Y, La, Bi) with three-layer fluorite layers by various cation doping and solid solution formation, and discovery of a new structure with sextuple fluorite-like blocks.

Academic Significance and Societal Importance of the Research Achievements

水分解光触媒は、クリーンでサスティナブルな水素生成方法として注目を集めている。今回我々は、近年高効率な光触媒として注目されている酸塩化物光触媒において、蛍石ブロックの拡張に着目した新しい物質設計の方針によって、複数の新規酸塩化物型光触媒の設計に成功した。この成果は、今後の高効率な光触媒開発につながることが期待できる。

Research Products

• [Journal Article] Lone-Pair-Induced Intra-and Interlayer Polarizations in Sillen-Aurivillius Layered Perovskite Bi4NbO8Br (2022)
  • Author(s): Zhong C, Ishii Y, Tassel C, Zhu T, Kato D, Kurushima K, Fujibayashi Y, Saito T, Ogawa T, Kuwabara A, Mori S, Kageyama H
  • Journal Title: Inorganic chemistry Volume: 61 Issue: 25 Pages: 9816-9822
  • DOI: 10.1021/acs.inorgchem.2c01358
  • Peer Reviewed
• [Journal Article] Bi12O17Cl2 with a Sextuple Bi‐O Layer Composed of Rock‐Salt and Fluorite Units and its Structural Conversion through Fluorination to Enhance Photocatalytic Activity (2022)
  • Author(s): Kato Daichi、Tomita Osamu、Nelson Ryky、Kirsanova Maria A.、Dronskowski Richard、Matsuzaki Yosuke、Brown Craig M.、Fujita Koji、Fujii Kotaro、Yashima Masatomo、Kobayashi Yoji、Saeki Akinori、Oikawa Itaru、Takamura Hitoshi、Abe Ryu、Kageyama Hiroshi、Gorelik Tatiana E.、Abakumov Artem M.
  • Journal Title: Advanced Functional Materials Volume: 32 Issue: 41 Pages: 2204112-2204112
  • DOI: 10.1002/adfm.202204112
  • Peer Reviewed / Int'l Joint Research
• [Presentation] 光触媒Bi12O17Cl2の結晶構造とトポケミカルフッ素化による構造変化 (2023)
  • Author(s): 加藤大地
  • Organizer: 日本化学会 第103春季年会
• [Presentation] 酸塩化物光触媒Bi12O17Cl2の構造とトポケミカルフッ素化 (2022)
  • Author(s): 加藤大地
  • Organizer: 日本セラミックス協会第35回秋季シンポジウム
• [Presentation] 蛍石層を有する酸塩化物の構造とトポケミカルフッ化反応 (2022)
  • Author(s): 加藤 大地
  • Organizer: 複合アニオン化合物の創成と新機能-最終発表会-
• [Presentation] Conduction Band Control of Oxyhalides with a Triple-Fluorite Layer for Visible Light Photocatalysis (2021)
  • Author(s): Daichi Kato
  • Organizer: International Core-to-Core Conference on Mixed Anion Research for Energy Conversion
  • Int'l Joint Research / Invited
• [Presentation] Conduction Band Control of Oxyhalides with a Triple-Fluorite Layer for Visible Light Photocatalysis (2021)
  • Author(s): Daichi Kato
  • Organizer: International Conference on Mixed-Anion Compounds
  • Int'l Joint Research / Invited