RELATIONSHIP BETWEEN THERMOELECTRIC PROPE RTIES AND MICROSTRUCTURE ONN-TYPE (BI2TE3)0.95 (BI2SE3)0.05 CERAMICS PREPARED FROM MIXED POWDERS

The n-type (Bi2Te3)(0.95)(Bi2Se3)(0.05) was synthesized by modified pu lverized and intermixed sintering elements (PIES) method and its figur e of merit was evaluated to be 1.8 x 10(-3)/K (25 degrees C). The mill ing mechanism obeyed to the Kick's law and Tanaka's equation, No aniso tropy of electrical transport phenomena in thermoelectric properties w as observed, because the microstructure consisted of non-oriented grai ns due to use the milling powders of Bi, Te, and Se as starting materi als, Thermal conductivity was smaller than that of single crystal by t he large phonon scattering due to small grain, and Seebeck coefficient and resistivity were smaller than that of single crystal due to imcom pletely formate solid solution and oxides of sintered body.