Structural and chemical heterogeneity in ancient glass probed using gas overcondensation, X-ray tomography, and solid-state NMR
(2020) In Materials Characterization 167.- Abstract
Rare ancient glasses have complex, multi-scale structures requiring more sophisticated and non-destructive pore characterisation techniques than usual. Homotattic patch models for nitrogen adsorption gave better fits to the isotherm data, more accurate void space descriptors, and also greater understanding of the underlying physical factors affecting adsorption, than standard BET. These homotattic patch models revealed the critical role of iron impurities in determining adsorption behaviour. Non-destructive sodium-23 NMR relaxometry validated the homotattic patch model for some natron glasses, and, in turn, was validated using multiple quantum magic-angle spinning (MQMAS) 23Na NMR. X-ray tomography images of the glasses... (More)
Rare ancient glasses have complex, multi-scale structures requiring more sophisticated and non-destructive pore characterisation techniques than usual. Homotattic patch models for nitrogen adsorption gave better fits to the isotherm data, more accurate void space descriptors, and also greater understanding of the underlying physical factors affecting adsorption, than standard BET. These homotattic patch models revealed the critical role of iron impurities in determining adsorption behaviour. Non-destructive sodium-23 NMR relaxometry validated the homotattic patch model for some natron glasses, and, in turn, was validated using multiple quantum magic-angle spinning (MQMAS) 23Na NMR. X-ray tomography images of the glasses showed the presence of large macroporous bubbles, while FEG-SEM revealed nanopores within the glass matrix. A newly-developed, gas overcondensation technique, suitable for small amounts of low porosity material, assessed the inter-relationship between the disparate levels in this hierarchical porosity. This technique demonstrated that the nanoporosity did not form a ‘corona’ around the bubbles, due to leaching from the glass, as initially supposed from tomography data, but was completely disconnected, and, thus, is probably associated with glass alkalinity. Gas overcondensation is demonstrated as a non-destructive alternative to mercury porosimetry for probing multi-scale porosity in rare artefacts.
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- author
- Rigby, Sean P. ; Stevens, Lee ; Meersmann, Thomas ; Pavlovskaya, Galina E. ; Rees, Gregory J. ; Henderson, Julian ; Bryant, Saffron J. ; Edler, Karen J. LU and Fletcher, Robin S.
- publishing date
- 2020-09
- type
- Contribution to journal
- publication status
- published
- keywords
- Ancient glass, Computerized X-ray tomography, FEG SEM, Gas sorption, Heterogeneity, Modeling, Overcondensation, Pore network, Solid-state NMR
- in
- Materials Characterization
- volume
- 167
- article number
- 110467
- publisher
- Elsevier
- external identifiers
-
- scopus:85087282811
- ISSN
- 1044-5803
- DOI
- 10.1016/j.matchar.2020.110467
- language
- English
- LU publication?
- no
- additional info
- Publisher Copyright: © 2020 Elsevier Inc.
- id
- d9a3e021-4d61-402f-b20d-9612d94e4ad0
- date added to LUP
- 2022-07-12 15:58:12
- date last changed
- 2022-08-12 12:57:58
@article{d9a3e021-4d61-402f-b20d-9612d94e4ad0, abstract = {{<p>Rare ancient glasses have complex, multi-scale structures requiring more sophisticated and non-destructive pore characterisation techniques than usual. Homotattic patch models for nitrogen adsorption gave better fits to the isotherm data, more accurate void space descriptors, and also greater understanding of the underlying physical factors affecting adsorption, than standard BET. These homotattic patch models revealed the critical role of iron impurities in determining adsorption behaviour. Non-destructive sodium-23 NMR relaxometry validated the homotattic patch model for some natron glasses, and, in turn, was validated using multiple quantum magic-angle spinning (MQMAS) <sup>23</sup>Na NMR. X-ray tomography images of the glasses showed the presence of large macroporous bubbles, while FEG-SEM revealed nanopores within the glass matrix. A newly-developed, gas overcondensation technique, suitable for small amounts of low porosity material, assessed the inter-relationship between the disparate levels in this hierarchical porosity. This technique demonstrated that the nanoporosity did not form a ‘corona’ around the bubbles, due to leaching from the glass, as initially supposed from tomography data, but was completely disconnected, and, thus, is probably associated with glass alkalinity. Gas overcondensation is demonstrated as a non-destructive alternative to mercury porosimetry for probing multi-scale porosity in rare artefacts.</p>}}, author = {{Rigby, Sean P. and Stevens, Lee and Meersmann, Thomas and Pavlovskaya, Galina E. and Rees, Gregory J. and Henderson, Julian and Bryant, Saffron J. and Edler, Karen J. and Fletcher, Robin S.}}, issn = {{1044-5803}}, keywords = {{Ancient glass; Computerized X-ray tomography; FEG SEM; Gas sorption; Heterogeneity; Modeling; Overcondensation; Pore network; Solid-state NMR}}, language = {{eng}}, publisher = {{Elsevier}}, series = {{Materials Characterization}}, title = {{Structural and chemical heterogeneity in ancient glass probed using gas overcondensation, X-ray tomography, and solid-state NMR}}, url = {{http://dx.doi.org/10.1016/j.matchar.2020.110467}}, doi = {{10.1016/j.matchar.2020.110467}}, volume = {{167}}, year = {{2020}}, }