Improvement of Thermoelectric Performance for Sb-Doped SnO2 Ceramics Material by Addition of Cu as Sintering Additive

The thermoelectric properties, such as the Seebeck coefficient value, S, electrical conductivity, sigma, and thermal conductivity, kappa, of Sb- and Cu-doped SnO2, that is, (Sn1-x-y Cu (x) Sb (y) )O-2, were investigated in detail. The addition of a small amount of CuO significantly improved the relative density of the SnO2 ceramics. However, the relative density slightly decreased with the excessive addition of CuO (more than x = 0.03). The addition of Sb2O5 should cause an increase in the number of charge carriers, resulting in an increased sigma value, and the addition of both CuO and Sb2O5 caused an increase in sigma and |S| at high temperature. The improvement of the sintering performance caused the enhancement of the thermoelectric performance. As the temperature region measured in this study (293-1073 K), the maximum ZT value was 0.29 at 1073 K for (Sn0.985Cu0.005Sb0.01)O-2.