Morphology Controlled Synthesis of Nanostructured Bi₂Te₃

Abstract

Nanostructured thermoelectric bismuth telluride (<TEX>$Bi_2Te_3$</TEX>) powders with various morphologies, such as nanoplates, nanorods, and nanotubes, were prepared by a hydrothermal method based on the reaction between <TEX>$BiCl_3$</TEX>, Te, and sodium ethylenediaminetetraacetate (<TEX>$Na_2$</TEX>-EDTA) at 150, 180, and <TEX>$210^{\circ}C$</TEX>. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED). The effect of reaction temperature on the morphology of the <TEX>$Bi_2Te_3$</TEX> particles was investigated, and the possible mechanism of morphology control was proposed.