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Updated: Jul 12, 2026

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Preparation of Carbon Nanosheets at Room Temperature
Published on: March 8, 2016
Phase transformations in carbon fullerenes at high shock pressures
Summary
Fullerenes (C60) transform into graphite under high pressure shock compression. This reconstructive transformation begins around 17 GPa, forming ordered graphite at higher pressures and temperatures, or an amorphous state above 50 GPa.
Area of Science:
- Materials Science
- Solid State Physics
- High-Pressure Physics
Background:
- Fullerenes (C60) are allotropes of carbon with unique molecular structures.
- Understanding the high-pressure behavior of C60 is crucial for developing novel carbon materials.
Purpose of the Study:
- To investigate the structural transformations of C60 under shock compression.
- To determine the pressure thresholds for C60's transformation to graphite and amorphous carbon.
Main Methods:
- Quasi-isentropic shock compression of C60 powders up to 110 GPa.
- Recovery of compressed specimens for analysis.
- Analysis using Raman spectroscopy and optical microscopy.
Main Results:
- C60 fullerenes remain stable up to 13-17 GPa.
- A rapid reconstructive transformation to graphite initiates near 17 GPa.
- Well-ordered graphite is recovered from 27 GPa and 600°C.
- An amorphous carbon state forms above 50 GPa.
Conclusions:
- The transformation to graphite is driven by pi-electron rehybridization.
- Shock compression provides a pathway to synthesize ordered graphite and amorphous carbon from C60.
- The pressure-induced structural changes in C60 are dependent on the applied pressure and temperature conditions.
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