In situ fabrication and thermoelectric properties of PbTe–polyaniline composite nanostructures

PbTe–polyaniline (PANi) composite nanopowders were in situ fabricated via an interfacial polymerization method at room temperature (~293 K). The phase structure, composition, and morphology of the powders were characterized by X-ray powder diffraction, infrared spectroscopy, transmission electron microscopy (TEM), and high-resolution TEM, respectively. The results show that the composite nanopowders consist of PbTe nanoparticles, PANi/PbTe core–shell nanostructure, and PbTe/PANi/PbTe three-layer sphere-like nanostructures. Formation mechanism of the PbTe–PANi composite nanostructures was proposed. The thermoelectric properties of the composite powders after being cold pressed into pellets were measured from 293 to 373 K. As the temperature increases from 293 to 373 K, the Seebeck coefficient of the composite decreases from 626 to 578 μV K−1 and the electrical conductivity increases from 1.9 to 2.2 S m−1.