Structure, thermal and physic-chemical properties of some chalcogenide alloys

Abstract

Bulk products of crystalline Bi2Se3-xTex alloys (x =0.0, 0.1, 0.3, 0.5) were prepared using simple melting synthesis. Crystalline features, microstructure and surface morphologies of the synthesized samples were examined via x-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive x-ray spectrometer. Elemental distribution was studied by energy dispersive analysis of X-ray (EDAX) spectroscopy. Polycrystalline of rhombohedral crystal structure was observed for the concerned samples. Perfect crystallinity and micro-scalability of the prepared were also reflected by the physic-chemical properties of each sample. Thermal behavior was studied throughout differential scanning calorimetry and thermogravimetric analysis showing that the samples are of high stability over high temperature range. Physic-chemical properties were determined in terms of experimental density. These properties were compactness value, molar volume and the percentage of free volume. Density of Bi2Se3 alloy was obtained at 7.37 gm/cm3. Te doping enhanced the density of the Bi2Se3-xTex system. The most Te doped alloy showed density of 9.018 gm/cm3. All other physic-chemical properties showed strong dependence on the Tea amounts in the system.