Abstract

SnO–P₂O₅ glasses are known to have a low glass transition temperature (T_g) and can be vitrified in combination with metal oxides and halides. In this study, the glass-forming region in the LiF–SnO–P₂O₅ system was determined and the properties of the obtained glasses were characterized. The starting materials were melted at 400 °C, and the glass-forming regions in the LiF–SnO–P₂O₅ system were determined using X-ray diffraction and thermal analysis. The glass-forming region was restricted to P₂O₅ contents of at least 36 mol %, which is close to pyrophosphate, in LiF-rich compositions (≥30 mol %). On the other hand, the region extended to near the orthophosphate composition with high SnO content, such as 10LiF·62SnO·28P₂O₅ (mol %). The glass transition temperature of the prepared glasses ranged from around 150 to 210 °C. Sn K-edge X-ray absorption fine structure spectra of 10LiF·62SnO·28P₂O₅ (mol %) glass showed that the valence of Sn is predominantly Sn(II). The X-ray photoelectron spectra confirm the formation of P–F bonds in the glasses. A chemical durability test in the ambient atmosphere revealed that the glasses in the LiF–SnO–P₂O₅ system have relatively high chemical durability. AC impedance measurement showed the glass has ionic conductivity in the order of 10⁻⁸ S cm⁻¹ at room temperature.

Credit: Shibata et al., Journal of the Ceramic Society of Japan, 134(3), 122–127 (2026), https://doi.org/10.2109/jcersj2.25145. Licensed under CC BY 4.0.