2023-07-18 デラウェア大学 (UD)
◆彼らはカーボン材料の中に存在するアルコール基が予想外にも酸性を示すことを発見しました。また、カーボン内の芳香族環が反応活性に影響を与えることも明らかになりました。これにより、より酸性の高いカーボン触媒を作るためには、アルコール基を増やす必要があることがわかりました。これにより、より効果的な材料作成技術や持続可能なプロセスの開発が可能になります。
＜関連情報＞
- https://www.udel.edu/udaily/2023/july/carbon-based-catalysts-performance-oxygen-catalysis-center-energy-innovation/
- https://www.nature.com/articles/s41467-023-37962-3
酸素を含む官能基で炭素表面の反応性を調整する Tuning the reactivity of carbon surfaces with oxygen-containing functional groups
Jiahua Zhou,Piaoping Yang,Pavel A. Kots,Maximilian Cohen,Ying Chen,Caitlin M. Quinn,Matheus Dorneles de Mello,J. Anibal Boscoboinik,Wendy J. Shaw,Stavros Caratzoulas,Weiqing Zheng & Dionisios G. Vlachos
Nature Communications Published:21 April 2023
DOI:https://doi.org/10.1038/s41467-023-37962-3
Abstract
Oxygen-containing carbons are promising supports and metal-free catalysts for many reactions. However, distinguishing the role of various oxygen functional groups and quantifying and tuning each functionality is still difficult. Here we investigate the role of Brønsted acidic oxygen-containing functional groups by synthesizing a diverse library of materials. By combining acid-catalyzed elimination probe chemistry, comprehensive surface characterizations, 15N isotopically labeled acetonitrile adsorption coupled with magic-angle spinning nuclear magnetic resonance, machine learning, and density-functional theory calculations, we demonstrate that phenolic is the main acid site in gas-phase chemistries and unexpectedly carboxylic groups are much less acidic than phenolic groups in the graphitized mesoporous carbon due to electron density delocalization induced by the aromatic rings of graphitic carbon. The methodology can identify acidic sites in oxygenated carbon materials in solid acid catalyst-driven chemistry.
