Controlling\nOxygen\nVacancies in Sr<sub>0.875</sub>La<sub>0.1</sub>TiO<sub>3</sub> with\nthe Nano Titanium for Optimizing\nThermoelectric Performance

The\nnanosized titanium powder exhibits a strong oxygen\ncapture\nability, which can effectively increase the carrier concentration\nof SrTiO<sub>3</sub>. However, it is essential to prevent oxidation\nbefore sintering. In this study, the impact of cold isostatic pressing\n(CIP) and calcination in an argon atmosphere on the microstructure\nand thermoelectric properties of Sr<sub>0.875</sub>La<sub>0.1</sub>TiO<sub>3</sub>/nano Ti ceramics was explored. The results indicate\nthat the carrier concentration of samples prepared by CIP can be significantly\nenhanced while simultaneously reducing the thermal conductivity through\na notable grain size reduction of titanium oxide and augmentation\nof oxygen vacancy concentration. At 1073 K, the <i>ZT</i> value of the sample calcined in air and prepared by CIP was 0.22,\nexhibiting a 27% enhancement compared to that of the sample formed\nby dry press. Therefore, the combination of CIP and nanoscale Ti provides\nan efficient approach to manipulate the electrical and thermal transport\nproperties of SrTiO<sub>3</sub> thermoelectric ceramics.