中国物理B ›› 2015, Vol. 24 ›› Issue (6): 67202-067202.doi: 10.1088/1674-1056/24/6/067202

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Influences of spark plasma sintering temperature on the microstructures and thermoelectric properties of (Sr0.95Gd0.05)TiO3 ceramics

李亮亮a b, 秦晓英c, 刘永飞c, 刘全桢a b   

  1. a SINOPEC Research Institute of Safety Engineering, Qingdao 266071, China;
    b State Key Laboratory of Chemical Safety, Qingdao 266071, China;
    c Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China
  • 收稿日期:2015-01-05 修回日期:2015-01-21 出版日期:2015-06-05 发布日期:2015-06-05
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11174292, 51101150, and 11374306).

Influences of spark plasma sintering temperature on the microstructures and thermoelectric properties of (Sr0.95Gd0.05)TiO3 ceramics

Li Liang-Liang (李亮亮)a b, Qin Xiao-Ying (秦晓英)c, Liu Yong-Fei (刘永飞)c, Liu Quan-Zhen (刘全桢)a b   

  1. a SINOPEC Research Institute of Safety Engineering, Qingdao 266071, China;
    b State Key Laboratory of Chemical Safety, Qingdao 266071, China;
    c Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China
  • Received:2015-01-05 Revised:2015-01-21 Online:2015-06-05 Published:2015-06-05
  • Contact: Li Liang-Liang E-mail:lgli@mail.ustc.edu.cn
  • About author:72.20.Pa; 72.80.Ga; 73.50.Lw
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11174292, 51101150, and 11374306).

摘要:

(Sr0.95Gd0.05)TiO3 (SGTO) ceramics are successfully prepared via spark plasma sintering (SPS) respectively at 1548, 1648, and 1748 K by using submicron-sized SGTO powders synthesized from a sol–gel method. The densities, microstructures, and thermoelectric properties of the SGTO ceramics are studied. Though the Seebeck coefficient shows no obvious difference in the case that SPS temperatures range from 1548 K to 1648 K, the electrical conductivity and the thermal conductivity increase remarkably due to the increase in grain size and density. The sample has a density higher than 98% theoretical density as the sintering temperature increases up to 1648 K and shows average grain sizes increasing from ~ 0.7 μm to 7 μm until 1748 K. As a result, the maximum of the dimensionless figure of merit of ~ 0.24 is achieved at ~ 1000 K for the samples sintered at 1648 K and 1748 K, which was ~ 71% larger than that (0.14 at ~ 1000 K) for the sample sintered at 1548 K due to the enhancement of the power factor.

关键词: sintering, transitional metal oxides, ceramics, thermoelectric properties

Abstract:

(Sr0.95Gd0.05)TiO3 (SGTO) ceramics are successfully prepared via spark plasma sintering (SPS) respectively at 1548, 1648, and 1748 K by using submicron-sized SGTO powders synthesized from a sol–gel method. The densities, microstructures, and thermoelectric properties of the SGTO ceramics are studied. Though the Seebeck coefficient shows no obvious difference in the case that SPS temperatures range from 1548 K to 1648 K, the electrical conductivity and the thermal conductivity increase remarkably due to the increase in grain size and density. The sample has a density higher than 98% theoretical density as the sintering temperature increases up to 1648 K and shows average grain sizes increasing from ~ 0.7 μm to 7 μm until 1748 K. As a result, the maximum of the dimensionless figure of merit of ~ 0.24 is achieved at ~ 1000 K for the samples sintered at 1648 K and 1748 K, which was ~ 71% larger than that (0.14 at ~ 1000 K) for the sample sintered at 1548 K due to the enhancement of the power factor.

Key words: sintering, transitional metal oxides, ceramics, thermoelectric properties

中图分类号:  (Thermoelectric and thermomagnetic effects)

  • 72.20.Pa
72.80.Ga (Transition-metal compounds) 73.50.Lw (Thermoelectric effects)