Synthesis of Sr{sub}(1-x)Y{sub}xTiO{sub}3 by the polymerized complex method and hot pressing

摘要

The SrTiO{sub}3 and Y-doped SrTiO{sub}3 polycrystalline sintered bodies were synthesized by the polymerized complex (PC) process and the subsequent hot pressing at 1473 K for 1h or at 1673 K for 2h in Ar atmosphere. The X-ray diffraction patterns of the SrTiO{sub}3 and Sr{sub}0.9Y{sub}0.1TiO{sub}3 samples synthesized by the PC process and hot pressing at 1473 K showed that these samples were mostly composed of the SrTiO{sub}3 single phase. On the other hand, in the case of Sr{sub}0.8Y{sub}0.2TiO{sub}3 sample, second phase such as Y{sub}2O{sub}3 precipitated detectably in the XRD patterns. The Seebeck coefficient, |S|, and the electrical resistivity of Sr{sub}0.9Y{sub}0.1TiO{sub}3 were lower than those of the SrTiO{sub}3, indicating the increase in carrier concentration. Both samples hot-pressed at 1673 K showed the power factors larger than those of the samples hot-pressed at 1473 K. Even though the Sr{sub}0.9Y{sub}0.1TiO{sub}3 sample hot-pressed at 1673 K showed the thermal conductivity higher than that of the other samples, the largest dimensionless figure of merit was obtained for this sample over the measured temperature range, because of its large power factor.