Wilding, MC;
Delaizir, G;
Benmore, CJ;
Gueguen, Y;
Dolhen, M;
Duclère, JR;
Chenu, S;
... McMillan, PF; + view all
(2016)
Structural studies of Bi2O3-Nb2O5-TeO2 glasses.
Journal of Non-Crystalline Solids
, 451
pp. 68-76.
10.1016/j.jnoncrysol.2016.07.004.
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Abstract
Bi2O3-Nb2O5-TeO2 glasses show unusual annealing behavior with appearance of spherulites within the matrix glass structure for the Bi0.5Nb0.5Te3O8 composition. The textures resemble those found previously among polyamorphic Al2O3-Y2O3 glasses containing metastably co-existing high- and low-density phases produced during quenching. However the spherulites produced within the Bi2O3-Nb2O5-TeO2 glass are crystalline and can be identified as an “anti-glass” phase related to β-Bi2Te4O11. We used high energy synchrotron X-ray diffraction data to study structures of binary and ternary glasses quenched from liquids within the Bi2O3-Nb2O5-TeO2 system. These reveal a glassy network based on interconnected TeO4 and TeO3 units that is related to TeO2 crystalline materials but with larger Te…Te separations due to the presence of TeO3 groups and non-bridging oxygens linked to modifier (Bi3 +, Nb5 +) cations. Analysis of the viscosity-temperature relations indicates that the glass-forming liquids are “fragile” and there is no evidence for a LLPT occurring in the supercooled liquid. The glasses obtained by quenching likely correspond to a high-density amorphous (HDA) state. Subsequent annealing above Tg shows mainly evidence for direct crystallization of the “anti-glass” tellurite phase. However, some evidence may exist for simultaneous formation of nanoscale amorphous spherulites that could correspond to the LDA polyamorph. The quenching and annealing behavior of Bi2O3-Nb2O5-TeO2 supercooled liquids and glasses is compared with similar materials in the Al2O3-Y2O3 system.
| Type: | Article |
|---|---|
| Title: | Structural studies of Bi2O3-Nb2O5-TeO2 glasses |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1016/j.jnoncrysol.2016.07.004 |
| Publisher version: | http://dx.doi.org/10.1016/j.jnoncrysol.2016.07.004 |
| Language: | English |
| Additional information: | © 2016. This manuscript version is published under a Creative Commons Attribution Non-commercial Non-derivative 4.0 International licence (CC BY-NC-ND 4.0). This licence allows you to share, copy, distribute and transmit the work for personal and non-commercial use providing author and publisher attribution is clearly stated. Further details about CC BY licences are available at http://creativecommons.org/licenses/by/4.0. Access may be initially restricted by the publisher. |
| Keywords: | Tellurite glass; Polyamorphism; Fragility; High energy X-ray diffraction |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Chemistry |
| URI: | https://discovery.ucl.ac.uk/id/eprint/1512727 |
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