Thermally stimulated crystallization of (20−x)LiO2-80TeO2-xWO3 glass system

Tellurite glasses of the (20−x)LiO₂-80TeO₂-xWO₃ system were synthesized (x=0, 5, and 10) and annealed at different temperatures, and the crystallization kinetics was studied using XRD, FTIR spectroscopy, and DSC techniques. XRD data evidenced the amorphous state of as-quenched samples, while thermally treated samples showed the growth of crystalline phases. FTIR spectroscopy was used to observe the evolution of the vibrational mode assigned to the TeO₂ phases. The presence of γ-TeO₂, α-TeO₂, and α-Li₂Te₂O₅ crystalline phases was observed for the sample TL, x=0, while only the first and second phases were observed for TLW5 and TLW10 samples, x=5 and 10, respectively, suggesting that WO₃ enters the structure preferentially as glass former, inhibiting the growth of the phase α-Li₂Te₂O₅.