Large Thermoelectric Power Factor in Pr-Doped SrTiO_3−δ Ceramics via Grain-Boundary-Induced Mobility Enhancement

We report a novel synthesis strategy to prepare high-performance bulk polycrystalline Pr-doped SrTiO₃ ceramics. A large thermoelectric power factor of 1.3 W m^–1 K^–1 at 500 °C is achieved in these samples. In-depth investigations of the electronic transport and microstructure suggest that this significant improvement results from a substantial enhancement in carrier mobility originating from the formation of Pr-rich grain boundaries. This work provides new directions to higher performance oxide thermoelectrics as well as possibly other properties and applications of this broadly functional perovskite material