Fabrication and thermoelectric properties of n-type (Sr0.9Gd0.1)TiO3 oxides

The n-type oxides (Sr0.9Gd0.1)TiO3 (SGTO) have been successfully prepared via a sol-gel process followed by solid-state sintering. The effects of sintering temperature on the thermoelectric (TE) properties of the SGTO samples have been investigated. The Seebeck coefficient showed no obvious difference, while the electrical conductivity increased with increasing sintering temperature, benefiting from an enhancement of densification. The maximum power factor (PF) value, similar to 20.5 mu W/K-2 cm at 370K in the metallic region, was observed for the sample sintered at 1748 K. As a result, the peak figure of merit (ZT) values for the samples sintered at higher than 1673K were in the range of 0.28-0.30. All the results indicate that such synthetic method provides a simple and effective way to prepare TE oxides.