Thermoelectric properties of Sr0.61Ba0.39Nb2O6-{\delta} ceramics   annealed in different oxygen-reduction conditions
  The thermoelectric properties of Sr0.61Ba0.39Nb2O6 ceramics, reduced in different conditions, were investigated in the temperature region from 323 K to 1073 K. The electrical transport behaviors of the samples are dominated by the thermal-activated polaron hopping, the Fermi glass behavior, and the Anderson localized behavior from low temperatures to high temperatures, respectively. The lattice thermal conductivity presents a plateau at high temperatures, indicating a glass-like thermal conduction behavior. Both the thermoelectric power factor and the thermal conductivity increase with the increasing degree of oxygen-reduction. Taking these two factors into account, the oxygen-reduction can still contribute to promoting the thermoelectric figure of merit. The highest ZT value (~0.19 at 1073 K) is obtained in the heaviest oxygen reduced sample. 
Y. Li, J. Liu, C.L. Wang, W.B. Su, Y.H. Zhu, J.C. Li and L.M. Mei
cond-mat.mtrl-sci