Abstract
The modulated differential scanning calorimetry study of amorphous Se90-xTe10Snx (x = 0, 2.5, 5, 7.5, and 10) is reported. The glass samples were fabricated using a conventional melt-quenching method. The processing of the non-isothermal data was performed using the advanced thermokinetics software package. To determine the variation of the activation energy for crystallisation as a function of reaction progress the main three isoconversional methods, namely the differential method of Friedman and the integral methods of Ozawa-Flynn-Wall and Vyazovkin, were used. Based on an ASTM E698 analysis of the data, the effect of Sn content was determined. The Avrami exponent of Se90-xTe10Snx was determined and found to be dependent on the Sn content, indicating different dimensions of growth. The prediction of the isothermal reaction progress was employed to calculate the reaction model, g(alpha). A very large increase in the specific heat values of Se90-xTe10Snx was observed at the respective glass transition temperatures, which were also found to be highly Sn-content dependent. The Raman spectra for Se90-xTe10Snx together with X-ray diffraction and possible glass structures are discussed. A remarkable change occurs at a Sn concentration of 10 at%, which indicates the formation of SnSe2.