Bismuth antimony telluride (Bi0.5Sb1.5Te3) is one of the famous ternary compounds with the best thermoelectric properties at near room temperature. In this research, Bi0.5Sb1.5Te3 powders were hydrothermally synthesized at different temperatures (100, 150, 190, and 230 °C) for 24 h. The deposition procedure of Bi0.5Sb1.5Te3 thin films was done by using thermal evaporation. Phase and microstructure of powders and thin films were investigated by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Moreover, size distribution of powders was checked out by particle size analyzer (PSA). The phase and microstructural results of the different synthesized powders confirmed that the Bi0.5Sb1.5Te3 thin film prepared by powder synthesized at 150°C for 24 h is the best choice for manufacturing material with good thermoelectric properties because of its nano-sized grains and high purity. The results showed that the Bi0.5Sb1.5Te3 thin film fabricated by powders synthesized at 150 °C has a single rhombohedral phase with a good semiconductor performance. The results of thermoelectric tests confirmed that the Bi0.5Sb1.5Te3 thin film fabricated using hydrothermal method and thermal evaporation deposition approach shows a high Seebeck coefficient (183.5 V) and low electronic thermal conductivity (1.32×10-4 W/m.k) at 298 K. Besides, the power factor values of 0.7, 2.59 and 2.9 μW/cm.K2 were obtained at 298, 373 and 473 K, respectively.

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