Transport Properties of La- doped SrTiO$_{3}$ Ceramics Prepared Using Spark Plasma Sintering*

In this work, thermoelectric transport properties of La-doped SrTiO$_{3}$ ceramics prepared using conventional solid state reaction and spark plasma sintering have been investigated. Room temperature power factor of single crystal strontium titanate (SrTiO$_{3})$, comparable to that of Bi$_{2}$Te$_{3}$, has brought new attention to this perovskite-type transition metal-oxide as a potential n-type thermoelectric for high temperature applications. Electronic properties of this model complex oxide, SrTiO$_{3}$ (ABO$_{3})$, can be tuned in a wide range through different doping mechanisms. In addition to A site (La-doped) or B site (Nb-doped) substitutional doping, introducing oxygen vacancies plays an important role in electrical and thermal properties of these structures. Having multiple doping mechanisms makes the transport properties of these perovskites more dependent on preparation parameters. The effect of these synthesis parameters and consolidation conditions on the transport properties of these materials has been studied.