Glass Transition and Crystallization Kinetics of Ge17.5As15Se52.5S15 Chalcogenide Glass

Abstract The glass transition and crystallization behavior of Ge17.5As15Se52.5S15 chalcogenide glass were analyzed by differential scanning calorimetry (DSC) under various heating and cooling rates ranging from 10 to 25 K/min. It was observed that both the glass transition temperature (Tg) and the peak crystallization temperature (Tp) systematically increase with increasing rate. The activation energy associated with the glass transition (Eg ≈ 250.5 kJ/mol) was evaluated using the Moynihan approach, whereas the crystallization activation energy (Ec ≈ 205.2 kJ/mol) was determined based on the Kissinger method. The calculated fragility index (m ≈ 28) suggests that the studied glass behaves as a relatively strong system. Overall, the obtained results indicate a stable thermal response and a notable resistance to crystallization, offering valuable insight into the kinetic and structural features of Ge–As–Se–S chalcogenide glass systems.