High-temperature thermoelectric properties of (Zn1 - xAlx)O
Abstract
A mixed oxide (Zn1-xAlx)O exhibits promising thermoelectric properties attaining a dimensionless figure of merit ZT of 0.30 at 1000 °C, which value is much superior to other oxides and quite comparable to conventional state-of-the-art thermoelectric materials. The addition of a small amount of Al2O3 to ZnO results in a large power factor of 10-15×10-4 W/mK2, showing a marked increase in the electrical conductivity while retaining moderate thermoelectric power. A large product of the carrier mobility and density of states would be responsible for the favorable electrical properties of the present oxide. A figure of merit Z=0.24×10-3 K-1 is attained by (Zn0.98Al0.02)O at 1000 °C, even with a high thermal conductivity. A predominant proportion of the phonon thermal conductivity promises a further improvement in the thermoelectric performance by selective enhancement of phonon scattering.
- Publication:
-
Journal of Applied Physics
- Pub Date:
- February 1996
- DOI:
- 10.1063/1.360976
- Bibcode:
- 1996JAP....79.1816O