Datasets for Tuning the reactivity of carbon surfaces with oxygen-containing functional groups
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 (XPS, AP-XPS, TPDE-MS), 15N isotopically labeled acetonitrile adsorption coupled with magic-angle spinning nuclear magnetic resonance (MAS NMR), machine learning, and density-functional theory calculations (DFT), we demonstrate that phenolic (-OH) is the main acid site in gas-phase chemistries and unexpectedly Ar/R-carboxylic (-COOH) groups are much less acidic than -OH 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.