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arXiv · 1909.08554

Investigating the high-temperature thermoelectric properties of n-type rutile TiO$_2$

Simon Thébaud·Christophe Adessi·Georges Bouzerar
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Abstract

Transition metal oxides are considered promising thermoelectric materials for harvesting high-temperature waste heat due to their stability, abundance and low toxicity. Despite their typically strong ionic character, they can exhibit surprisingly high power factors $σS^2$, as in n-type SrTiO$_3$ for instance. Thus, it is worth examining other transition metal oxides that might surpass the performances of SrTiO$_3$. This theoretical paper investigates the thermoelectric properties of n-type rutile TiO$_2$, which is the most stable phase of titanium oxide up to 2000 K. The electronic structure is obtained through ab initio calculations, while the prominent features of strong electron-phonon interaction and defects states are modelled using a small number of parameters. The theoretical results are compared with a wealth of experimental data from the literature, yielding very good agreements over a wide range of carrier concentrations. This validates the hypothesis of band conduction in rutile TiO$_2$ and allows the prediction of the high-temperature thermoelectric properties.

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Simon Thébaud, Christophe Adessi, Georges Bouzerar. 2019-11-23. Investigating the high-temperature thermoelectric properties of n-type rutile TiO$_2$. https://doi.org/10.1103/physrevb.100.195202

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