open access

https://hdl.handle.net/2115/86457

Thin film growth and thermoelectric properties of electron conducting oxides

英語

Ba1/3CoO2

2022-07

社団法人 日本セラミックス協会(The Ceramic Society of Japan)

Journal of the Ceramic Society of Japan

130(7)

471-476

Thermoelectric energy conversion attracts increasing attention as a technology for effectively reusing waste heat. Although thermoelectric materials that show a good thermoelectric figure of merit (ZT) have been proposed thus far, they are not practical at all because they are thermally and chemically unstable and composed of toxic elements. In order to address this issue, the author focused on metal oxides as thermoelectric materials that are thermally and chemically stable and non-toxic, and succeeded in significantly improving thermoelectric ZT by using two-dimensional electron gas and elemental substitution. In 2007, the author focused on Prof. Dresselhaus's theory that by confining carriers in a quantum well thinner than the thermal de Broglie wavelength, the thermoelectric power can be greatly enhanced without lowering the conductivity, and the oxide superlattice was introduced. In 2010, the author demonstrated a field-effect transistor structure on an insulator SrTiO3 crystal and measured thermopower while inducing 2DEG with a thickness of 2 nm by applying a voltage, similar to an artificial superlattice. It was discovered that the thermoelectric field can be increased 5 times as much as the bulk ratio. Furthermore, in 2020, the author found that the Ba1/3CoO2 thin film with a layered crystal structure had the highest room temperature ZT of 0.11 among metal oxides. (C) 2022 The Ceramic Society of Japan. All rights reserved.

学術雑誌論文

Version of Record

1882-0743