Calorimetric study on Ge23Se67Sb10–0.5CsCl glass

Abstract

The mechanical behavior of Ge23Se67Sb10 glass can be improved by adding CsCl facilitating the nano-crystaline formation. Understanding the crystallization mechanism of chalcogenide glass can help in directing the subsequent annealing processing and tuning the microstructure and physical properties. In this work, 99.5Ge23Se67Sb10–0.5CsCl glass was prepared and its transformation kinetics was investigated under non-isothermal conditions with heating rate up to 400 K min−1. Using Vogel–Fulcher–Tammann equation, the ideal glass transition temperature was determined as T 0g = 434.1 K. Using the classical JMA theory, the average activation energy and average growth exponent were determined as 135.0 and 2.4 kJ mol−1, while using the model considering impingements (MCI), the two parameters were determined as 120.9 and 3.2 kJ mol−1, respectively. Compared to JMA theory, the MCI model can fit the transition curves better, and it shows that the growth mode of the present glass is between two-dimension and three-dimension. By comparing with the result of Ge23Se67Sb10 glass, it is found that addition of CsCl can reduce the growth dimension and activation energy during crystallization.