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Updated: Jul 8, 2025
07:24
Visible-light Induced Reduction of Graphene Oxide Using Plasmonic Nanoparticle
Published on: September 22, 2015
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Alternatives for Epoxides in Graphene Oxide.
Gaurav Jhaa1, Pattath D Pancharatna2, Musiri M Balakrishnarajan1
1Chemical Information Sciences Lab, Department of Chemistry, Pondicherry University, Pondicherry 605014, India.
Journal of Chemical Information and Modeling
|December 14, 2023
Summary
Graphene oxide (GO) structures are clarified: epoxides are stable and planar, ruling out 1,3-ethers. Larger holes in GO are explained by favored 1,6-diones, resolving long-standing debates in nanomaterials.
Area of Science:
- Materials Science
- Nanotechnology
- Computational Chemistry
Background:
- Graphene oxide (GO) is a nanomaterial with an unresolved structural complexity.
- Existing models propose various oxygen-containing functional groups, but their stability and distribution remain unclear.
Purpose of the Study:
- To investigate the structural and electronic properties of functional groups in graphene oxide.
- To determine the stability and preferred distribution of epoxides, cyclic ethers, and vinylogous carbonyls on the graphene lattice.
Main Methods:
- Systematic theoretical inquiry into hexagonal and periodic constraints on functional groups.
- Comparative analysis of geometric and electronic structures, stability, and distribution.
- Evaluation of steric repulsion and bond-breaking mechanisms.
Main Results:
- Epoxides are surprisingly stable and planar, conserving the graphene backbone.
- Larger cyclic ethers like 1,3-ethers are ruled out due to severe steric repulsion.
- 1,6-diones in trans orientation are thermodynamically favored, explaining observed holes in GO.
Conclusions:
- The study resolves the longstanding debate on the existence of 1,3-ethers in GO.
- Epoxidation is a key structural feature, maintaining graphene's planarity.
- Thermodynamically favored 1,6-diones explain macroscopic defects in graphene oxide.
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