Decoupling the Electrical Conductivity and Seebeck Coefficient in the RE2SbO2 Compounds through Local Structural Perturbations

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• 作者：Peng L. Wang ; Taras Kolodiazhnyi ; Jinlei Yao ; Yurij Mozharivskyj
• 刊名：The Journal of the American Chemical Society
• 出版年：2012
• 出版时间：January 25, 2012
• 年：2012
• 卷：134
• 期：3
• 页码：1426-1429
• 全文大小：243K
• 年卷期：v.134,no.3(January 25, 2012)
• ISSN：1520-5126

文摘

Compromise between the electrical conductivity and Seebeck coefficient limits the efficiency of chemical doping in the thermoelectric research. An alternative strategy, involving the control of a local crystal structure, is demonstrated to improve the thermoelectric performance in the RE₂SbO₂ system. The RE₂SbO₂ phases, adopting a disordered anti-ThCr₂Si₂-type structure (I4/mmm), were prepared for RE = La, Nd, Sm, Gd, Ho, and Er. By traversing the rare earth series, the lattice parameters of the RE₂SbO₂ phases are gradually reduced, thus increasing chemical pressure on the Sb environment. As the Sb displacements are perturbed, different charge carrier activation mechanisms dominate the transport properties of these compounds. As a result, the electrical conductivity and Seebeck coefficient are improved simultaneously, while the number of charge carriers in the series remains constant.