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Updated: May 22, 2026
07:24
Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Cobalt-mediated crystallographic etching of graphite from defects
Rui Wang1, Jiayi Wang, Hao Gong
1Department of Electrical and Computer Engineering, National University of Singapore, 117576, Singapore.
Small (Weinheim an Der Bergstrasse, Germany)
|April 28, 2012
Summary
Cobalt-assisted crystallographic etching creates well-defined zigzag edges on graphite. This method enables the fabrication of graphitic ribbons for potential use in graphene nanoribbon transistors.
Area of Science:
- Materials Science
- Nanotechnology
- Surface Chemistry
Background:
- Conventional graphite etching methods often create trenches.
- Controlling edge morphology in etched graphite is crucial for advanced applications.
Purpose of the Study:
- To investigate cobalt-assisted crystallographic etching of graphite.
- To demonstrate controlled fabrication of graphitic structures with specific edge chirality.
Main Methods:
- High-temperature (above 750 °C) etching of graphite in a hydrogen environment using cobalt.
- Characterization using transmission electron microscopy (TEM) and Raman spectroscopy.
- Defect engineering using oxygen plasma to guide etching.
Main Results:
- Cobalt fills and enlarges etch-pits, forming well-defined pits with 60°/120° edge orientations.
- Raman analysis confirms the formation of zigzag edges.
- Defects successfully directed the etching process, enabling controlled edge formation.
- Fabrication of graphite strips and graphitic ribbons with purely zigzag edges.
Conclusions:
- Cobalt-assisted crystallographic etching offers precise control over graphite morphology.
- The ability to create zigzag edges is demonstrated, paving the way for nanoribbon fabrication.
- Fabricated graphitic ribbons hold potential for graphene nanoribbon transistors.
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