Electrical transport properties of microwave-synthesized Bi2Se3−xTex nanosheet

Abstract

Tellurium (Te) doped bismuth selenide (Bi₂Se_3−xTe_x) nanosheets have been successfully synthesized by the microwave-assisted method in the presence of ethylene glycol (EG). The obtained products were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), selected-area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy techniques. The electrical transport properties of the nanosheets are investigated by measuring the electrical conductivity and the Seebeck coefficient at temperatures ranging from 298 to 523 K. The power factor values of the Bi₂Se_3−xTe_x nanosheet vary with different doping concentrations of Te, and the maximum power factor can reach 178 μW m⁻¹ K⁻² at 523 K for Bi₂Se_2.7Te_0.3, indicating the potential application in thermoelectric devices.