Synthesis and Characterization of BiSe Thermoelectric Nanopowders

ABSTRACT

In order to synthesize Bi₂Se₃ nanopowders by a solvothermal synthesis method, ethylenediamine, dimethylformamide, acetone, absolute ethanol, and deionized water were respectively used as a solvent, using BiCl3 and elemental Se powders as starting materials and KBH4 as a reductant at 180oC for different times. X-ray diffraction was used for examining the phase composition of the products. The results showed that pure Bi2Se3 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 Bi₂Se₃ nanosheets and nanoparticles was proposed.