The effect of powder synthesis method on thermoelectric properties of Bi2Te2.7Se0.3 thin films

The aim of this research is to study the influence of synthesis process of Bi 2 Te 2.7 Se 0.3 compound on thermoelectric properties of its thin films. Therefore, in this study, Bi 2 Te 2.7 Se 0.3 powders were produced by two procedures of mechanical milling and hydrothermal. Subsequently, using the synthesized powder, Bi 2 Te 2.7 Se 0.3 thin films were fabricated by thermal evaporation method. The effects of the synthesis methods on the X-ray diffraction pattern, microstructure, and thermoelectric properties of the thin films were evaluated. The results showed a significant increment in the three parameters of the electrical conductivity (458 (Ω cm) −1 ), the Seebeck coefficient (273.9 (Ω cm) −1 ), and the power factor (1.3 µW/K 2 cm) when the hydrothermal synthesis method has been employed for the production of the powder. The reason can be attributed to the tiny pores and their homogenous distribution in the thin films manufactured from the hydrothermally synthesized powder. The large particles of the powder led to higher electrical conductivity. The results of this research help to expand the knowledge to the improvement of the efficiency of thermoelectric materials.