open access

https://hdl.handle.net/2115/77935

Electron Sandwich Doubles the Thermoelectric Power Factor of SrTiO3

英語

two-dimensionality

2019-05-08

Wiley-Blackwell

physica status solidi (a)

216(9)

1800832

Thermoelectric materials convert a temperature difference into electricity through a phenomenon known as the Seebeck effect, and their efficiency is determined by the dimensionless figure of merit, ZT (equivalent to S-2.sigma.kappa(-1)). Currently, most materials exhibiting high ZT values (ZT>1) are based on heavy metal compounds, but these materials have low thermal/chemical stability. In this regard, conducting metal oxides attract much attention for thermoelectric power generations at high temperatures based on their advantages in thermal stability over heavy metal compounds. However, the thermoelectric performance of metal oxides is usually low. Here the authors review that an enhanced two-dimensionality is efficient for enhancing the thermoelectric power factor of metal oxides. The authors fabricate SrTiO3-based superlattices of [N unit cell SrTi1-xNbxO3|11 unit cell SrTiO3](10), of which the de Broglie wavelengths can be tuned by the substitution of Nb. The maximum power factor of the superlattice composed of the long de Broglie wavelength SrTi1-xNbxO3 exceeds approximate to 5mWm(-1)K(-2), which doubles the value observed from the optimized bulk SrTi1-xNbxO3. This finding can help to reduce the amount of wasted heat and thus wasted fossil fuel in daily activities and industrial factories.

学術雑誌論文

Accepted Manuscript

This is the peer reviewed version of the following article: Zhang, Y. and Ohta, H. (2019), Electron Sandwich Doubles the Thermoelectric Power Factor of SrTiO3. Phys. Status Solidi A, 216: 1800832, which has been published in final form at https://doi.org/10.1002/pssa.201800832 . This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.

1862-6300