Preparation and thermoelectric properties of Nd and Dy co-doped SrTiO3 bulk materials

[Display omitted] •Nd doped SrTiO3 enhances the electrical conductivity for bulk samples.•Dy doped SrTiO3 enhances the Seebeck coefficient for bulk samples.•Sr0.83Dy0.03Nd0.14TiO3 sample performs the highest power factor, 1250 μW/mK2.•Nd and Dy co-doping can efficiently reduce the thermal conductivity for SrTiO3.•Sr0.87Dy0.07Nd0.06TiO3 sample performs the highest values of ZT, 0.19 at 673 K. To improve the thermoelectric properties of SrTiO3, Nd3+ and Dy3+ ions were doped in SrTiO3. Sr0.8Nd0.2TiO3 and Sr0.9Dy0.1TiO3 powders were prepared via a traditional solid state reaction, respectively. Two powders were mixed and followed the stoichiometric formula: Sr0.1x+0.8Dy0.1xNd0.2(1-x)TiO3 (x = 0, 0.3, 0.5, 0.7, 1). With the decreasing content of Dy, electrical conductivity of bulks is enhanced, but Seebeck coefficient decreases. The maximum electrical conductivity is 1435 S/cm at 423 K for Sr0.8Nd0.2TiO3 (x = 0) bulk. According to the Seebeck coefficient results, all samples are characterized by n-type semiconductor-like behavior. The maximum value of power factor is 1250 μW/mK2 at 573 K for Sr0.83Dy0.03Nd0.14TiO3 (x = 0.3) bulk. The maximum value of ZT, ZT = 0.19 at 673 K is obtained for Sr0.87Dy0.07Nd0.06TiO3 (x = 0.7) bulk with 7 mol% Dy and 6 mol% Nd, which is a result of the high power factor and low thermal conductivity.