Details
| Original language | English |
|---|---|
| Article number | 17416 |
| Pages (from-to) | 58-67 |
| Number of pages | 10 |
| Journal | Journal of non-crystalline solids |
| Volume | 423-424 |
| Early online date | 20 May 2015 |
| Publication status | Published - 1 Sept 2015 |
Abstract
Abstract The structural investigation of hydrated borate glasses provides new insights on the influence of water on boron speciation using spectroscopic methods. In the present study three soda-lime-borate glasses (NCBx with x = 5, 15 and 25 corresponding to xNa2O, 10CaO, 90 - xB2O3 in mol%) were prepared with water content up to 8 wt.%. The water speciation in the glasses was derived by near-infrared (NIR) spectroscopy while boron speciation was investigated by 11B MAS NMR (Magic Angle Spinning Nuclear Magnetic Resonance). For the three glasses effective molar absorption coefficients were determined experimentally for the bands at 5200 cm- 1 and 4600 cm- 1, corresponding to combination modes of H2O molecules and OH-groups, respectively. In contrast to silicate glasses, in which at most ~ 2 wt.% H2O are dissociated to OH-groups, the amount of dissociated H2O may even exceed 5 wt.% in borate glasses. The fraction of tetrahedral to total boron (N4 = BIV / BIV + BIII) is predominantly controlled by the ratio of Na2O + CaO / B2O3, but only weakly affected by the water content of the glasses. When increasing the H2O content from 0 to 8 wt.%, N4 increases from 25% to 26% for NCB5 and from 42% to 47% for NCB25 glasses.
Keywords
- Glass structure, High pressure, Spectroscopy, Water-bearing glasses
ASJC Scopus subject areas
- Materials Science(all)
- Electronic, Optical and Magnetic Materials
- Materials Science(all)
- Ceramics and Composites
- Physics and Astronomy(all)
- Condensed Matter Physics
- Materials Science(all)
- Materials Chemistry
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In: Journal of non-crystalline solids, Vol. 423-424, 17416, 01.09.2015, p. 58-67.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Water- and boron speciation in hydrous soda-lime-borate glasses
AU - Bauer, U.
AU - Behrens, H.
AU - Fechtelkord, M.
AU - Reinsch, S.
AU - Deubener, J.
N1 - Funding Information: The authors are grateful for the financial support from DFG via SPP1594 . The authors appreciated the careful sample preparation of Julian Feige. We also thank Robert Balzer, Wiebke Ponick, Marc Krey and Tim Müller for the assistance of measurements and Anna-Maria Welsch (all U Hannover) for their helpful discussions.
PY - 2015/9/1
Y1 - 2015/9/1
N2 - Abstract The structural investigation of hydrated borate glasses provides new insights on the influence of water on boron speciation using spectroscopic methods. In the present study three soda-lime-borate glasses (NCBx with x = 5, 15 and 25 corresponding to xNa2O, 10CaO, 90 - xB2O3 in mol%) were prepared with water content up to 8 wt.%. The water speciation in the glasses was derived by near-infrared (NIR) spectroscopy while boron speciation was investigated by 11B MAS NMR (Magic Angle Spinning Nuclear Magnetic Resonance). For the three glasses effective molar absorption coefficients were determined experimentally for the bands at 5200 cm- 1 and 4600 cm- 1, corresponding to combination modes of H2O molecules and OH-groups, respectively. In contrast to silicate glasses, in which at most ~ 2 wt.% H2O are dissociated to OH-groups, the amount of dissociated H2O may even exceed 5 wt.% in borate glasses. The fraction of tetrahedral to total boron (N4 = BIV / BIV + BIII) is predominantly controlled by the ratio of Na2O + CaO / B2O3, but only weakly affected by the water content of the glasses. When increasing the H2O content from 0 to 8 wt.%, N4 increases from 25% to 26% for NCB5 and from 42% to 47% for NCB25 glasses.
AB - Abstract The structural investigation of hydrated borate glasses provides new insights on the influence of water on boron speciation using spectroscopic methods. In the present study three soda-lime-borate glasses (NCBx with x = 5, 15 and 25 corresponding to xNa2O, 10CaO, 90 - xB2O3 in mol%) were prepared with water content up to 8 wt.%. The water speciation in the glasses was derived by near-infrared (NIR) spectroscopy while boron speciation was investigated by 11B MAS NMR (Magic Angle Spinning Nuclear Magnetic Resonance). For the three glasses effective molar absorption coefficients were determined experimentally for the bands at 5200 cm- 1 and 4600 cm- 1, corresponding to combination modes of H2O molecules and OH-groups, respectively. In contrast to silicate glasses, in which at most ~ 2 wt.% H2O are dissociated to OH-groups, the amount of dissociated H2O may even exceed 5 wt.% in borate glasses. The fraction of tetrahedral to total boron (N4 = BIV / BIV + BIII) is predominantly controlled by the ratio of Na2O + CaO / B2O3, but only weakly affected by the water content of the glasses. When increasing the H2O content from 0 to 8 wt.%, N4 increases from 25% to 26% for NCB5 and from 42% to 47% for NCB25 glasses.
KW - Glass structure
KW - High pressure
KW - Spectroscopy
KW - Water-bearing glasses
UR - http://www.scopus.com/inward/record.url?scp=84929624355&partnerID=8YFLogxK
U2 - 10.1016/j.jnoncrysol.2015.05.004
DO - 10.1016/j.jnoncrysol.2015.05.004
M3 - Article
AN - SCOPUS:84929624355
VL - 423-424
SP - 58
EP - 67
JO - Journal of non-crystalline solids
JF - Journal of non-crystalline solids
SN - 0022-3093
M1 - 17416
ER -