Improved thermoelectric power factor and conversion efficiency of perovskite barium stannate

Abstract

In the pursuit of high thermoelectric conversion efficiency, both high operating temperature and high figure of merit ZT are desirable. Thermoelectric materials used in high-temperature power generation are still in great demand. Here we demonstrate the n-type doped barium stannate (BaSnO3) behaves as a robust candidate, as a high-temperature thermoelectric material, due to its ultrahigh power factor and excellent structural and chemical stability. A systematic calculation focused on the geometric, electronic and thermoelectric transport properties of BaSnO3 is performed by using density functional theory combined with Boltzmann transport theory. It can be noticed that the electrical conductivity of BaSnO3 is improved dramatically when it is n-type doped, resulting from the small effective mass and extraordinary high mobility. The power factor maximum reaches 1.5 × 10-3 W m-1 K-2 at 1200 K with the optimal carrier concentration 1.6 × 1019 cm-3, which suggests the great potential of BaSnO3 as an n-type high temperature thermoelectric material.