Molecular-Based Photoelectrochemical Cell Consisting of Two TiO2 electrodes for Overall Solar Water Splitting Under Bias-Free Conditions

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05502
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 34010:Inorganic/coordination chemistry-related
• Research Institution: Kyushu University
• Principal Investigator: Ozawa Hironobu 九州大学, 理学研究院, 准教授 (30572804)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 太陽光水分解 / 錯体触媒 / 錯体色素 / 光電気化学 / 二酸化チタン

Outline of Final Research Achievements

In order to develop the molecular-based photoelectrochemical cells promoting overall water splitting even under bias-free conditions, the backward electron transfer from the conduction band of TiO2 to the water oxidation catalyst should be suppressed effectively. In this study, several water oxidation catalysts having spacer units have been synthesized, and the TiO2 electrodes modified with these water oxidation catalysts have been also fabricated for this purpose. Moreover, a dinuclear complex having both the photosensitizing and the catalytic units has been synthesized, and the TiO2 electrode modified with this dinuclear complex has been also prepared. Several valuable insights into the development of the molecular-based photoelectrochemical cells for overall water splitting have been obtained in this study.

Free Research Field

錯体化学、無機化学

Academic Significance and Societal Importance of the Research Achievements

本研究では、光増感サイトと触媒反応サイトを単一分子化した二核錯体の合成、およびこれを修飾したTiO2電極の作製を行い、この修飾電極が電気化学的な酸素生成触媒機能を示すことを明らかにした。TiO2電極表面における光増感サイトと触媒反応サイトでの電子移動や、
酸素生成触媒反応に関して非常に有用な知見を得ることができ、各種光エネルギー変換反応に関する研究の飛躍的な進展につながると期待される。また、各種光エネルギー変換反応に関する研究が飛躍的に進展することによって、持続可能な社会の早期実現に向けて大きく貢献できると考えられる。