The glassy state of the amorphous V2O5–NiO–TeO2 samples Original Research Article

The glass transition temperature dependence to heating rate and therefore the activation energy (ΔH⁎) of the glass transition of (60-x)V2O5–xNiO–40TeO2 oxide glasses with 0≤x≤20 (in mol%) were investigated at heating rates φ (=3 6, 9, 10 and 12 K/min) using differential scanning calorimetry (DSC). The heating rate dependence of Tg was used to investigate the applicability of different theoretical models describing the glass transition. Using the application of Moynihan and Kissinger et al. models to the present data, different values of (ΔH⁎) at each different heating-rate regions were obtained. The fragility parameter (m=ΔH⁎/R Tg) was ∼24.98 for x=10 mol%, suggesting that this glass may be considered as a rather strong glass (fragility index m∼>20 is an indication of fragile glass). Also the compositional dependence of Tg and ΔH⁎ was investigated.