Thermal properties of Sb xSe 100− x glasses studied by modulated temperature differential scanning calorimetry

Abstract

The compositional dependence of the thermal properties of Sb x Se 100− x melt quenched glasses (0.01 < x < 25 at.%) has been studied. Modulated temperature differential scanning calorimetry technique has been applied to determine the thermal properties of Se-rich Sb x Se 100− x chalcogenide glasses in the glass transition and crystallization regions. The reversing and non-reversing heat flows through the glass transformations were measured during both heating and cooling scans. T g (glass transition), Δ H g (relaxation enthalpy), C p (specific heat capacity), Δ C p (change in C p at T g), Δ H c (crystallization enthalpy), T p (peak crystallization rate temperature) and T c (crystallization onset temperature) which determine the thermal events in the glass were calculated from the experimental curves. Some of the structurally controlled parameters such as T g, C p, and T c − T g reveal local extrema when the Sb–Se glass system reaches 1 at.% Sb and 15 at.% Sb approximate concentrations, where the glass forming ability was also maximal. We discuss the results in terms of possible dimensional structural changes, `size effect' and local stoichiometry.