Study of thermoelectric properties of Sr0.92A0.08TiO3 (A=Yb / Tm) perovskite oxide using density functional theory method

Abstract The first principle methods have been employed to investigate electronic and thermoelectric properties of Sr0.92Yb0.08TiO3 and Sr0.92Tm0.08TiO3 perovskite-oxide based molded samples. Generalized gradient approximation (GGA) with Hubbard U parameter is used by WIEN2k code for the calculations. The straight band line was observed in the band structure of both studied samples. This was generated from 4f-orbitals as shown in partial density of state diagrams. It is also noticed that Yb and Tm doped in SrTiO3 changed the perovskite-based oxide from a wideband insulator to metallic nature. A thermoelectric power factor of Sr0.92Tm0.08TiO3 sample is higher than that of Sr0.92Yb0.08TiO3, this is as a result of its huge electrical conductivity. The dependent of chemical potential to temperature was revealed in the study where high value of power factor was recorded for high temperature.