Oxidation-accelerated crystallization of (GeS2)y(Sb2S3)1-y chalcogenide glasses

Influence of oxygen presence on the crystallization behavior of (GeS2)y(Sb2S3)1-y glasses (for y up to 0.3) was studied by differential scanning calorimetry, X-ray diffraction analysis and infrared microscopy - the study was performed in dependence on particle size. The oxygen was found to significantly accelerate crystallization from mechanically induced defects for the (GeS2)0.1(Sb2S3)0.9 composition and to sustain the intensity of crystal formation in case of the (GeS2)0.2(Sb2S3)0.8 and (GeS2)0.3(Sb2S3)0.7 compositions. On the other hand, presence of oxygen influenced neither the morphology of the crystallites, nor the actual crystallization model-free and model-based kinetics. Direct microscopic observation confirmed strict surface crystallization for all studied composition. Compositional evolutions of the viscosity data and microscopically determined crystal growth rate curves have shown that it is the exceptionally high crystal growth rate and crystallization tendency (compared to the minor-to-moderate contribution of viscosity itself) that are responsible for the significant influenceability of the (GeS2)0.1(Sb2S3)0.9 crystallization by the presence of oxygen.