Preparation and characterization of Bi2S3 compound semiconductor

Bi2S3 single crystals were grown by the chemical vapour transport technique using ammonium chloride (NH4Cl) as a transporting agent. The stoichiometry of Bi2S3 single crystal was confirmed by energy-dispersive analysis of X-rays (EDAX). The powder X-ray diffraction (XRD) pattern showed that Bi2S3 crystals belong to the orthorhombic phase with calculated lattice constant a = 11.14 Å, b = 11.30 Å and c = 3.96 Å. Scanning electron microscopy (SEM) pictures indicate the presence of layer lines on the surface of crystals thereby proving that these crystals are grown by layer by layer mechanism. We studied the transport properties viz. Hall effect, resistivity, thermoelectric power and thermal conductivity on Bi2S3 pellets. Raman spectroscopy and thermal gravimetric analysis (TGA) were carried out on Bi2S3 single crystal for studying their optical and thermal behaviours.