Synthesis and electrical properties of Bi<sub>2</sub>Te<sub>3</sub>-based thermoelectric materials doped with Er, Tm, Yb and Lu
Nanopowders of Bi<sub>2</sub>Te<sub>3</sub> and Ra<sub>1</sub>BiL<sub>9</sub>Te<sub>3 </sub>(where R = Er, Tm, Yb, Lu) were obtained by solvothermal-microwave synthesis. Powdery materials were compacted by cold isostatic compression with the following annealing in argon medium. The influence of doping agent on the structure and the characteristics of the derived materials were investigated. It was demonstrated that the substitution of rare earth element (2at%) into bismuth telluride lattice leads to decrease of the electric resistivity and to increase of the Seebeck coefficient. The best thermoelectric properties was obtained for the sample of bismuth telluride alloyed with thulium.