Development and activation of stand-alone photocatalyst systems for visible-light-driven water splitting

2018 Fiscal Year Final Research Report

• Project/Area Number: 15H05494
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Energy-related chemistry
• Research Institution: Shinshu University (2018); The University of Tokyo (2015-2017)
• Principal Investigator: Hisatomi Takashi 信州大学, 先鋭領域融合研究群環境・エネルギー材料科学研究所, 准教授(特定雇用) (00637481)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 粉末光触媒 / 水分解 / 太陽エネルギー / 水素 / 半導体 / 光触媒シート / Zスキーム / 耐久性

Outline of Final Research Achievements

Particulate photocatalyst sheets showing one of the highest solar-to-hydrogen energy conversion efficiencies among particulate photocatalyst systems via the two-step excitation overall water splitting reaction were developed by fixing hydrogen evolution photocatalysts and oxygen evolution photocatalysts onto conductive layers. Through various analyses, it was revealed that combining photocatalysts and conductive materials that yielded superior performance as photoelectrodes and suppressing backward reactions occurring on the conductive layer were essential for the improvement of the water splitting activity of photocatalyst sheets. Moreover, it became possible to split water by using photocatalytic materials that could utilize visible light up to 600 nm alone by applying surface-modified particulate photocatalysts to the photocatalyst sheet system.

Free Research Field

物理化学

Academic Significance and Societal Importance of the Research Achievements

本研究課題で開発した光触媒シートは，二種類の光触媒粒子が導電層上に物理的に強固に固定されているため，光触媒粒子表面の化学的性質によらず様々な材料を応用できる．また，活性を阻害する恐れのある添加物を用いる必要がない．そのため，従来の光触媒反応システムの課題は本質的に克服されている．今後，水分解用光触媒材料の改良が進めば，大規模で高効率に太陽光水分解反応を駆動する光触媒シートを作製することが可能となり，持続可能な水素製造プロセスの実現に向けて前進できると期待される．