Study on structure-activity relationship of oxyhalide photocatalysts for achieving highly efficient water splitting

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K14719
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 36020:Energy-related chemistry
• Research Institution: Kyoto University
• Principal Investigator: Hajime Suzuki 京都大学, 工学研究科, 助教 (10862873)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: 人口光合成 / 光触媒 / 水分解 / 可視光 / 酸ハロゲン化物

Outline of Final Research Achievements

The following two topics were intensively studied: (1) development of new Sillen-type oxyhalide photocatalysts and band structure analysis of them and (2) synthesis of new multi-layered perovskite oxyiodide photocatalysts. In the topic (1), a Sillen-type SrBi3O4Cl3 photocatalyst was newly developed. The origin of visible light absorption of SrBi3O4Cl3 was revealed via a detail analysis of its band structure. In the topic (2), new multi-layered perovskite oxyiodide photocatalysts were synthesized and their physicochemical properties were evaluated. Introduction of iodide was found to change the band levels, light absorption, and photocatalytic activity.

Free Research Field

光触媒

Academic Significance and Societal Importance of the Research Achievements

クリーンな水素製造技術の一つとして半導体光触媒を用いた水分解が注目され、太陽光スペクトルの大部分を占める可視光を利用可能な新規水分解用光触媒の開発が盛んに行われている。本研究では、Sillen(-Aurivillius)型層状酸ハロゲン化物の各層（フルオライト層、ペロブスカイト層、ハロゲン層）が電子物性や光触媒活性に与える影響の解明に取り組み、新規酸ハロゲン化物光触媒の開発とその物性・活性評価を通じて、その一端を明らかにした。得られた知見を今後の材料開発にフィードバックすることで、光触媒として最適な構造を有する酸ハロゲン化物を設計できれば、本系の水分解効率の大幅な向上も期待できる。