Crystallization kinetics in as-synthesis high yield of a-Se100−xTex nanorods

The paper reports the synthesis of high yield of a-Se100−xTex (x = 3, 6, 9 and 12) nanorods using one of the simplest approaches i.e. melt quenching technique. The morphology and microstructure of as-prepared alloys is studied using scanning Electron Microscopy (SEM) and transmission electron microscopy (TEM). From SEM investigation, it is observed that these powder samples of a-SexTe100−x contain high yield of nanorods and their diameter is of the order of several hundred nanometers. The XRD patterns of these samples suggest that these nanorods are amorphous in nature. Crystallization kinetics in these nanorods of amorphous SexTe100−x glasses are studied at different heating rates (5, 10, 15 and 20 K min−1) under non-isothermal condition using differential scanning calorimetry. It is observed that the value of glass transition temperature and crystallization temperature varies with the composition and heating rate. From the heating rate dependence of glass transition temperature and crystallization temperature, the activation energy for structural relaxation (ΔEt), the activation energy of crystallization (ΔEc) and the order parameter (n) have been calculated. The composition dependence of the activation energy for thermal relaxation and activation energy for crystallization is discussed in terms of the structure of Se–Te glassy system.