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Updated: Jan 7, 2026
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Published on: June 12, 2019
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Structural Mechanism for Gas Permeability in Noncrystalline Carbon under Pressure
Zhidan Zeng1, Hongbo Lou1,2, Fujun Lan1,2,3
1Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, China.
Journal of the American Chemical Society
|January 5, 2026
Summary
High pressure enables novel compounds, with nanostructured diamond capsules (NDCs) preserving volatiles. Gas diffusion into NDCs occurs via structural defects in glassy carbon, not layer spacing, enabling new precursor development.
Area of Science:
- Materials Science
- High-Pressure Physics
- Nanotechnology
Background:
- High pressure transforms volatiles, creating novel compounds and properties.
- Nanostructured diamond capsules (NDCs) are crucial for preserving high-pressure volatiles.
- Understanding gas diffusion into carbon precursors is vital for NDC synthesis.
Purpose of the Study:
- Investigate pressure-induced gas diffusion pathways in glassy carbon.
- Identify structural mechanisms enabling volatile penetration into carbon precursors.
- Explore alternative amorphous carbon materials for NDC synthesis.
Main Methods:
- In situ high-pressure synchrotron X-ray diffraction.
- Small-angle X-ray scattering.
- Transmission electron microscopy.
Main Results:
- Gas diffusion into glassy carbon occurs through disordered structural defects.
- Interlayer spacing between graphene-like layers is not the primary diffusion pathway.
- Amorphous carbon nanospheres are identified as viable NDC precursors.
Conclusions:
- Gas permeability in disordered carbon under pressure is governed by structural defects.
- This mechanism guides the selection and engineering of carbon precursors for NDCs.
- Optimized NDCs can enhance applications involving high-pressure volatiles.
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