Bismuth-telluride Thermoelectric Nanoparticles Synthesized by Using a Polyol Process

Bismuth-telluride (Bi2Te3) nanoparticles have been synthesized by using BiCl3 and TeCl4 as reactants, ethyleneglycol as the polyol solvent. The microstructures showed that the synthesized bismuth telluride nanoparticles had the 200 nm-sized polycrystalline structures resulting from aggregates of nanocrystallites. The X-ray diffraction (XRD) results revealed that the phase of the nanoparticles consisted of mainly Bi2Te3. The sintered Bi2Te3 materials exhibited grain size of 300 nm and significantly decreased the thermal conductivities compared to those of micro-grained bulk materials due to increased phonon-scattering at the nanograin boundaries.