Thermal Stability of ZnO/Tm<sub>2</sub>O<sub>3</sub> Substitution on Tellurite-Zinc-Bismuth-Sodium (TZBN) Glasses

Tm 2 O 3 doped tellurite-zinc-bismuth-sodium (TZBN) glass samples with varying compositions were prepared through melt quenching technique. The composition of these glass was 60 TeO 2 - (30-x) ZnO - 5 Bi 2 O 3 - 5 Na 2 O - x Tm 2 O 3 with (x = 0.5; 1.0; 1.5; 2.0 and 2.5 mol%). We reported the result of a systematic study of the thermal properties of these glass by using differential thermal analysis (DTA). The thermal characteristics of these glass (glass transition, T g , crystallization, T c , and melting, T m ) increased significantly with Tm 2 O 3 content and the glasses were more thermally stable (greater ΔT=T c -T g ). The glass transition value slightly increased from 314 to 323 °C otherwise thermal stability ΔT changed from 112 to 131°C. The ratio of T g /T m values for TZBN doped Thulium glasses were about 0.558 to 0.589, indicated that these glasses possess good thermal stability. The Hruby parameter (K g ) with Tm 3+ doped in this study improved glass-forming ability, which is desirable for various applications such as optical fibers drawing and sensors.