2025-04-07 東京科学大学
＜関連情報＞
- https://www.isct.ac.jp/ja/news/1bm0s4x166b8
- https://www.isct.ac.jp/plugins/cms/component_download_file.php?type=2&pageId=&contentsId=1&contentsDataId=1111&prevId=&key=e80d40a0b9a0ffeffbccf4ec7896eb72.pdf
- https://advanced.onlinelibrary.wiley.com/doi/10.1002/adfm.202425452
六方晶ペロブスカイト酸化物の酸素欠陥工学による硫化物のスルホンへの好気的酸化触媒性能の向上 Oxygen Defect Engineering of Hexagonal Perovskite Oxides to Boost Catalytic Performance for Aerobic Oxidation of Sulfides to Sulfones
Keiju Wachi, Masashi Makizawa, Takeshi Aihara, Shin Kiyohara, Yu Kumagai, Keigo Kamata
Advanced Functional Materials Published: 03 April 2025
DOI:https://doi.org/10.1002/adfm.202425452
Abstract
Oxygen defect engineering in metal oxides is a promising approach to designing efficient active sites for catalytic oxidation involving surface lattice oxygen. In the present study, a combined approach focusing on the structure of oxygen sites (face-shared vs corner-shared) and B-site substitution in an ABO3 hexagonal perovskite oxide is investigated. Ru-substituted SrMnO3 nanoparticles (SrMn1−xRuxO3) efficiently catalyzes the aerobic oxidation of thioanisole to sulfone with high selectivity (>99%) even at 30 °C, which is much lower than the temperatures required for the same reaction catalyzed using previously reported Mn- and Ru-based oxide catalysts (80–150 °C). Only a small amount of Ru incorporation (x = 0.01) substantially enhances its catalytic performance. The present catalyst can be reused five times and applied to the aerobic oxidation of various sulfides to afford the corresponding sulfones. Mechanistic studies reveal a bifunctional property of SrMn1−xRuxO3, where surface lattice oxygen is involved in sulfide oxidation, and the strong adsorption of sulfoxides onto the surfaces contributes to the rapid successive oxidation of sulfoxide. Catalyst reducibility estimations and density functional theory calculations indicate that the intrinsic role of Ru is likely to enhance the oxygen transferability of face-shared Mn4+–O–Mn4+ species.
