Thermoelectric properties of reduced TiO2 -SrF2 composites

Highly stable thermoelectric materials based on inexpensive elements have great potential for heat recovery in high temperature applications. TiO2-d and SrTiO3 based thermoelectric materials are of great interest due to this reason. In this study TiO2-SrF2 based compounds were produced, to study the effect of fluorine on the thermoelectric properties of TiO2 type materials. From XPS measurements it is clear that some exchange from the TiO2-SrF2 happens forming a TiOxFy type phase. The electronic properties of the compound are very similar to the electronic properties of reduced TiO2 while some improvement is seen in the reduction of the thermal conductivity. A higher activation energy in the SrF2 rich samples might allow for increased electronic conductivity at higher temperatures interesting for further studies.