Temperature-induced phase transformation in (As1–<i>x</i>Bi<i>x</i>)2S3 glasses

Here, we study the kinetics of pre-crystallization and crystallization transformations in (As1–xBix)2S3 glasses (0.08 ≤ x ≤ 0.20). The crystallization process was analyzed using the known Kissinger method based on the differential thermal analysis curves obtained at non-isothermal conditions. Transformations from the amorphous to the partially crystalline state have a complex character. For all the glasses under study, the thermostimulated transformations reveal the presence of two overlapping crystallization subprocesses, each of them being controlled by a different energy barrier. The first subprocess is shown to dominate at high heating rates and is characterized by an essentially lower activation energy compared to that of the second crystallization subprocess, which dominates at low heating rates. X-ray diffraction measurements show that in the (As1–xBix)2S3 samples at high heating rates mostly the nucleation of Bi2S3, crystallites occurs while in the slower heating mode additionally As4S4 and As4S3 crystallites are formed.