Synthesis and Characterization of Bi2Se3 Thermoelectric Nanopowders

Abstract

In order to synthesize Bi 2 Se 3 nanopowders by a solvothermal synthesis method, ethylenediamine, dimethylfor-mamide, acetone, absolute ethanol, and deionized water were respectively used as a solvent, using BiCl 3 and elemental Se powders as starting materials and KBH 4 as a reductant at 180 o C for different times. X-ray diffraction was used for examining the phase composition of the products. The results showed that pure Bi 2 Se 3 nanopowders were successfully synthesized only when deionized water was used as the solvent. Transmission electron microscopy observation revealed that the nanopowders consisted of big polygonal nanosheets and small irregular nanoparticles. The formation mechanism of the Bi 2 Se 3 nanosheets and nanoparticles was proposed.