Structural and thermal properties of chemically synthesized Bi2Te3 nanoparticles

Bi2Te3 nanoparticles (NPs) have been synthesized at 50 degrees C by a low-cost wet chemical route. The structural properties of product sample were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy. Thermal properties of product sample were investigated by differential scanning calorimetry (DSC), thermogravimetric (TG), and transient plane source techniques. The XRD and selected area electron diffraction of Bi2Te3 NPs result showed the polycrystalline nature with a rhombohedral (R3m) structure of the nanocrystallites. The average grain size of Bi2Te3 NPs was found to be about 30 nm by XRD and TEM measurements. DSC result shows one endothermic peak and one exothermic peak. TG result shows that only 48 % mass loss has occurred in Bi2Te3 sample. The obtained lower thermal conductivity of Bi2Te3 NPs is about 0.3 W m(-1) K-1 at room temperature, which is caused by considering the crystalline nature of this material.