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Updated: Jun 22, 2026
08:26
Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route
Published on: April 3, 2016
Pair distribution function analysis of pressure treated zeolite Na-A
Jennifer E Readman1, Paul M Forster, Karena W Chapman
1School of Chemistry, University of Birmingham, Edgbaston, Birmingham, UKB15 2TT.
Chemical Communications (Cambridge, England)
|June 9, 2009
Summary
High pressure causes zeolite Na-A to lose its crystal structure, becoming amorphous. However, the local bonds between sodium and oxygen atoms remain intact during this pressure-induced amorphisation.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Zeolites are crystalline aluminosilicates with diverse applications.
- Understanding their structural response to extreme conditions is crucial for materials science.
- Previous studies have explored zeolite behavior under pressure, but mechanisms remain debated.
Purpose of the Study:
- To investigate the structural changes in zeolite Na-A under high pressure.
- To elucidate the mechanism of pressure-induced amorphisation in zeolites.
- To determine the fate of local bonding environments during structural transformation.
Main Methods:
- X-ray scattering experiments were performed on zeolite Na-A samples.
- Pair distribution function (PDF) analysis was applied to the scattering data.
- Samples were subjected to pressures up to 8 GigaPascals (GPa).
Main Results:
- High pressure (up to 8 GPa) induces amorphisation in zeolite Na-A.
- The aluminosilicate framework loses its long-range crystallographic order.
- Local sodium-to-oxygen bonding environments are preserved during amorphisation.
Conclusions:
- Zeolite Na-A undergoes pressure-induced amorphisation via framework disordering.
- Local coordination and bonding are more robust than long-range order under pressure.
- This finding offers insights into the structural resilience of framework materials.
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