Effect of Co-Doping on Thermoelectric Properties of <i>n</i>-Type Bi<sub>2</sub>Te<sub>3</sub> Nanostructures Fabricated Using a Low-Temperature Sol-Gel Method

oleh: Syed Irfan, Muhammad Aizaz Ud Din, Muhammad Qaisar Manzoor, Deliang Chen

Format: Article
Diterbitkan: MDPI AG 2021-10-01

Deskripsi

In this work, a novel low-temperature double solvent sol-gel method was used to fabricate (Sm, Ce, Gd) and (Sn, Se, I) co-doped at Bi and Te-sites, respectively, for Bi<sub>2</sub>Te<sub>3</sub> nanostructures. The phase-purity and high crystallinity of as-synthesized nanostructures were confirmed using X-ray diffraction and high-resolution transmission electron microscopy. The nanopowders were hot-pressed by spark plasma sintering into bulk pellets for thermoelectric properties. The spark plasma sintering temperature significantly affects the Seebeck coefficient and electrical conductivity of bulk Bi<sub>2</sub>T<sub>e3</sub> pellets. The electrical conductivities of co-doped samples decrease with an increase in the temperature, but conversely, the Seebeck coefficient is linearly increasing. The power factor showed that the co-dopants enhanced the thermoelectric properties of Bi<sub>2</sub>Te<sub>3</sub> nanopowders.