Effects of Oxygen-Reduction on Thermoelectric Properties of Sr_0.61Ba_0.39Nb₂O₆ Ceramics

Abstract:

The thermoelectric properties of Sr_0.61Ba_0.39Nb₂O₆ ceramics, reduced in various conditions, were investigated in the temperature range from 323K to 1073K. Both the electrical resistivity and the absolute Seebeck coefficient decreased with the deepening degree of oxygen-reduction. However, the decrease of the electrical resistivity had a major influence on the thermoelectric power factor. Therefore, the more heavily reduced sample can gain the higher value of thermoelectric power factor. It has been observed that the thermal conductivity increased with the deepening degree of oxygen-reduction, which indicates that the scattering of the oxygen vacancies produced by reduction does not play a dominant role in the thermal conduction. In spite of the increase of the thermal conductivity, the oxygen-reduction still promoted the thermoelectric figure of merit via the increase of the thermoelectric power factor. And the most heavily reduced Sr_0.61Ba_0.39Nb₂O₆ ceramic has the highest thermoelectric figure of merit (~0.18 at 1073 K) among all the samples.

• Periodical: Materials Science Forum (Volume 787)
• Pages: 210-214
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.787.210
• Online since: April 2014
• Authors: Yi Li, Jian Liu*, Chun Lei Wang, Wen Bin Su, Yuan Hu Zhu, Ji Chao Li, Liang Mo Mei
• Keywords: Oxygen Reduction, Sr_0.61Ba_0.39Nb₂O₆, Thermoelectric

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