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Fluid-cell Raman Spectroscopy for operando Studies of Reaction and Transport Phenomena during Silicate Glass Corrosion
Published on: May 9, 2025
Correlation between alkaline earth diffusion and fragility of silicate glasses
Morten M Smedskjaer1, Yuanzheng Yue, Joachim Deubener
1Section of Chemistry, Aalborg University, DK-9000 Aalborg, Denmark.
The Journal of Physical Chemistry. B
|July 25, 2009
Summary
Alkaline earth ion diffusion in SiO(2)-Na(2)O-Fe(2)O(3)-RO glasses correlates with liquid fragility. Lowering glass fragility enhances inward cationic diffusion, impacting nanolayer formation.
Area of Science:
- Materials Science
- Glass Chemistry
- Solid State Chemistry
Background:
- Investigating the relationship between liquid fragility and ion diffusion in oxide glasses.
- Focusing on alkaline earth ions (Mg, Ca, Sr, Ba) in SiO(2)-Na(2)O-Fe(2)O(3)-RO glass systems.
Purpose of the Study:
- To study the correlation between liquid fragility and inward diffusion of alkaline earth ions.
- To understand how chemical composition affects diffusion and fragility.
Main Methods:
- Inducing inward diffusion of alkaline earth ions via Fe(3+) to Fe(2+) reduction using H(2)/N(2) gas.
- Conducting experiments around the glass transition temperature (T(g)).
Main Results:
- Inward diffusion depth decreases with Mg(2+), Ca(2+), Sr(2+), Ba(2+), while fragility increases.
- The ratio of activation energies (E(d)/E(eta)) increases with liquid fragility.
Conclusions:
- Liquid fragility is directly correlated with the inward diffusion of alkaline earth ions.
- Lowering glass fragility enhances inward cationic diffusion, offering a method to control nanolayer formation.
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