Materials Science and Engineering, King Abdullah University of Science and Technology, Thuwal-23955-6900, Saudi Arabia.
ACS Appl Mater Interfaces. 2013 Aug 14;5(15):7268-73. doi: 10.1021/am4015956. Epub 2013 Jul 23.
We report the evolution of high temperature thermoelectric properties of SrTiO3 thin films doped with Nb and oxygen vacancies. Structure-property relations in this important thermoelectric oxide are elucidated and the variation of transport properties with dopant concentrations is discussed. Oxygen vacancies are incorporated during growth or annealing in Ar/H2 above 800 K. An increase in lattice constant due to the inclusion of Nb and oxygen vacancies is found to result in an increase in carrier density and electrical conductivity with simultaneous decrease in carrier effective mass and Seebeck coefficient. The lattice thermal conductivity at 300 K is found to be 2.22 W m(-1) K(-1), and the estimated figure of merit is 0.29 at 1000 K.
我们报告了 Nb 和氧空位掺杂 SrTiO3 薄膜高温热电性能的演变。阐明了这种重要热电氧化物的结构-性能关系，并讨论了输运性质随掺杂浓度的变化。氧空位是在 800K 以上的 Ar/H2 中生长或退火时掺入的。发现由于 Nb 和氧空位的掺入导致晶格常数增加，从而导致载流子密度和电导率增加，同时载流子有效质量和 Seebeck 系数减小。在 300K 时晶格热导率为 2.22Wm(-1)K(-1)，估计在 1000K 时的品质因数为 0.29。
