The effect of ZnO ↔ Ta{sub 2}O{sub 5} substitution on the structural and thermal properties of SiO{sub 2}-ZnO-SrO-CaO-P{sub 2}O{sub 5} glasses

Journal Article · Fri Apr 15 00:00:00 EDT 2016 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2016.03.004· OSTI ID:22587139

Alhalawani, Adel M.F. ^[1]

---

1. Department of Mechanical & Industrial Engineering, Ryerson University, Toronto, ON (Canada)

A series of glasses based on the system 48SiO{sub 2}-(36-X) ZnO-6CaO-8SrO-2P{sub 2}O{sub 5}-XTa{sub 2}O{sub 5} with X varying from 0 mol% (Ta0) to 8 mol% (Ta4) were fabricated. The structural features as a function of Ta{sub 2}O{sub 5} content were investigated by network connectivity (NC) calculations, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The thermal properties of the glasses were obtained by performing simultaneous thermal analysis (STA). XRD showed that all compositions were predominantly amorphous, however the incorporation of tantalum pentoxide (Ta{sub 2}O{sub 5}) resulted in a small degree of crystallinity within the sample. Replacing ZnO with Ta{sub 2}O{sub 5} increases the glass transition, crystallization and melting temperatures. Further, Ta{sub 2}O{sub 5} incorporation results in higher thermal stability suggesting a greater glass forming tendency and the insertion of Ta in the glass network. XPS and FTIR spectroscopy revealed that Ta behaves as a glass former and that Zn has an intermediary role in the vitreous network. - Highlights: • ZnO substitution for Ta{sub 2}O{sub 5} in the glass system SiO{sub 2}-ZnO-CaO-SrO-P{sub 2}O{sub 5} is presented. • ZnO substitution results in greater glass forming tendency. • Ta{sub 2}O{sub 5} addition results in the formation of Si−O−Ta and Ta−O−Ta linkages. • Ta{sub 2}O{sub 5} addition increases the glass thermal stability. • ZnO behaves as an intermediate in this glass system.

• OSTI ID: 22587139
• Journal Information: Materials Characterization, Vol. 114; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
CALCIUM OXIDES
CRYSTALLIZATION
FOURIER TRANSFORM SPECTROMETERS
FOURIER TRANSFORMATION
GLASS
INFRARED SPECTRA
MELTING
MELTING POINTS
PHOSPHATES
PHOSPHORUS OXIDES
SILICA
SILICON OXIDES
STABILITY
STRONTIUM OXIDES
TANTALUM
TANTALUM OXIDES
THERMAL ANALYSIS
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY
ZINC OXIDES