Morphological Control of Bi2Te3 Nanotubes and Their Thermoelectric Properties

Highly uniform Bi2Te3 nanotubes with various morphologies are synthesized via a solution process using Te nanowires as a sacrificial template. The morphology of Bi2Te3 nanotubes can be controlled by varying the solvent system. The reaction between Bi and Te in triethylene glycol (TEG) produces Bi2Te3 nanotubes with plate-like surface morphology, whereas rough surface morphology of the Bi2Te3 nanotubes is obtained by the reaction in ethylene glycol (EG). The crystal structures and morphologies of nanotubes are investigated X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The effect of solvent on the evolution of morphology of the Bi2Te3 nanotubes is investigated. The effect of surface morphology on the thermoelectric properties is discussed.