Atomic-level understanding of catalytic reaction processes by operando observation of 3D active structures and surface-adsorbed species

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H01802
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 29020:Thin film/surface and interfacial physical properties-related
• Research Institution: Hokkaido University
• Principal Investigator: Takakusagi Satoru 北海道大学, 触媒科学研究所, 教授 (30359484)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: オペランド偏光全反射蛍光XAFS法 / オペランド偏光変調赤外反射分光法 / 活性点三次元構造解析 / 担持金属触媒

Outline of Final Research Achievements

Oxide-supported metal catalysts, in which active metal species (monatomic or nanoparticles) are supported on oxide surfaces, are the most widely used in practical applications. In order to understand catalytic reaction processes and to provide guidelines for further improvement of catalytic performance, it is essential to clarify factors affecting catalytic performance (electronic state and 3D structure of active metal sites and behavior of surface adsorbed species) under reaction conditions, and then to obtain information on precise structure-activity relationships and reaction mechanisms. In this study, the operando polarization-dependent total reflection fluorescence XAFS (PTRF-XAFS) technique developed in the 18H01864 project was upgraded and improved, and a new operando-polarized-modulation infrared reflection absorption spectroscopy was developed to evaluate all the factors affecting catalytic performance.

Free Research Field

触媒化学、表面科学、放射光科学

Academic Significance and Societal Importance of the Research Achievements

固体触媒はファインケミカルズや医薬品の合成、自動車排ガスの無害化など、産業や環境に有用な多くの化学反応に用いられており、SDG実現に向けて触媒の更なる高性能化（極めて高い効率で欲しい物質だけを得る）が求められている。しかし、「触媒反応中にどういった電子状態及び立体構造を有する表面ナノ構造が形成され、そこには吸着種がどのような状態で存在して最終生成物を与えるのか？」という触媒制御因子に関する情報を得る評価技術は確立されておらず、厳密な構造-活性相関の取得や反応機構の解明は難しかった。本研究によって、こうした情報の取得が可能になり、今後の触媒設計に関してより明確な指針を与えることが期待できる。