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Updated: Aug 2, 2025
08:59
Dry Oxidation and Vacuum Annealing Treatments for Tuning the Wetting Properties of Carbon Nanotube Arrays
Published on: April 15, 2013
15.1K
Tuning the reactivity of carbon surfaces with oxygen-containing functional groups.
Jiahua Zhou1,2, Piaoping Yang1,2, Pavel A Kots1
1Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, 19716, USA.
Nature Communications
|April 21, 2023
Summary
Phenolic groups are the primary acid sites in oxygen-containing carbons for gas-phase reactions. Carboxylic groups show lower acidity due to electron delocalization in graphitized carbon materials.
Area of Science:
- Materials Science
- Catalysis
- Surface Chemistry
Background:
- Oxygen-containing carbons are valuable metal-free catalysts and supports.
- Distinguishing and quantifying the roles of different oxygen functional groups remains challenging.
Purpose of the Study:
- To investigate the specific role of Brønsted acidic oxygen-containing functional groups.
- To quantify and tune the acidity of these functional groups in carbon materials.
Main Methods:
- Synthesis of a diverse library of oxygen-containing carbon materials.
- Acid-catalyzed elimination probe chemistry and surface characterizations.
- 15N isotopically labeled acetonitrile adsorption with solid-state NMR, machine learning, and DFT calculations.
Main Results:
- Phenolic groups were identified as the dominant Brønsted acid sites in gas-phase reactions.
- Carboxylic groups exhibited lower acidity than phenolic groups in graphitized mesoporous carbon.
- Electron density delocalization induced by aromatic rings was shown to reduce carboxylic group acidity.
Conclusions:
- The study elucidates the distinct acidity of phenolic and carboxylic groups in graphitized carbon.
- The developed methodology enables the identification of acidic sites in oxygenated carbon materials for solid acid catalyst applications.
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