Hydrothermal synthesis and thermoelectric properties of nanostructured Bi0.5Sb1.5Te3 compounds

Abstract Single-phase Bi 0.5 Sb 1.5 Te 3 compounds have been prepared by hydrothermal synthesis at 150 °C for 24 h using SbCl 3 , BiCl 3 and tellurium powder as precursors. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) have been applied to analyze the phase distributions, microstructures and grain sizes of the as-grown Bi 0.5 Sb 1.5 Te 3 products. It is found that the hydrothermally synthesized Bi 0.5 Sb 1.5 Te 3 nanopowders have a morphology dominated by irregular hexagonal sheets due to the anisotropic growth of the crystals. The Bi 0.5 Sb 1.5 Te 3 nanosheets are parallelly stacked in certain direction to form sheet-agglomerates attribute to the temperature gradients in the solution.