A kinetic analysis on non-isothermal glass-crystal transformation in Ge1-xSnxSe2.5 (0 ≤ x ≤ 0.5) glasses

Differential scanning calorimetry (DSC) has been employed at five different heating rates to investigate the glass-crystal transformation in Ge1-xSnxSe2.5 (0 <= x <= 0.5) glasses under non-isothermal conditions. From the dependence of glass transition temperature on the heating rate 'alpha', the activation energy of glass transition, Et, has been calculated on the basis of the Kissinger model. Results indicate that T-g and Et attain their minimum values at 0.3 at. wt% of Sn. The crystallization process has been investigated using Kissinger, Matusita, Augis and Bennett, and Gao and Wang models. Various kinetic parameters such as activation energy of crystallization, E-c, Avrami exponent (n), dimensionality of growth (m), frequency factor (K-o) and crystallization rate factor (K) have been calculated for a better understanding of the growth mechanism. The obtained kinetic parameters indicate that stability of glassy samples decreases upto 0.3 at. wt% of Sn and increases on further addition of Sn.