Enhanced thermoelectric performance of Zn‐doped oxyselenides: BiCu1−xZnxSeO
Enhanced thermoelectric performance of Zn‐doped oxyselenides: BiCu1−xZnxSeO
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DOI：
10.1002/pssa.201431347
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发表时间：
2014-11
期刊：
影响因子：
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通讯作者：
G. Ren;S. Butt;Yaochun Liu;J. Lan;Yuanhua Lin;C. Nan;F. Fu;X.F. Tang
中科院分区：
文献类型：
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作者：
G. Ren;S. Butt;Yaochun Liu;J. Lan;Yuanhua Lin;C. Nan;F. Fu;X.F. Tang
采用固相反应结合等离子体活化烧结（PAS）的方法制备了高性能BiCuSeO热电陶瓷。相组成和微观结构研究表明，复合材料具有细化的晶粒尺寸（600-700纳米）与纳米结构的ZnSe第二相。我们的研究结果表明，Zn掺杂可以导致载流子浓度发生很大变化（从0.036 × 1020 cm−3到1.50 × 1020 cm−3），从而导致室温下电导率增加三个数量级。在873 K时，10%的Zn掺杂实现了4.21 µWcm− 1 K −2的最高功率因数。另一方面，由于细化的晶粒、点缺陷和ZnSe相的纳米夹杂物，晶格热导率已被显著抑制。通过10%的Zn掺杂，BiCuSeO氧硒化物在873 K下的无量纲优值（ZT）可以达到0.90，这使得Zn掺杂的BiCuSeO成为热电应用的有希望的候选者。
High‐performance thermoelectric BiCuSeO ceramics have been prepared by solid state reaction combined with plasma activated sintering (PAS). Phase compositional and microstructural studies indicate composites having refined grain sizes (600–700 nm) with nanostructured ZnSe secondary phase. Our results reveal that Zn doping can lead to a large change in the carrier concentration (from 0.036 × 1020 cm−3 to 1.50 × 1020 cm−3), thus resulting in an increased electrical conductivity of three orders of magnitude at room temperature. The highest power factor of 4.21 µWcm−1K−2 at 873 K has been achieved by 10% Zn doping. On the other hand, the lattice thermal conductivity has been suppressed significantly due to refined grains, point defects and the nano‐inclusions of ZnSe phase. The dimensionless figure of merit (ZT) could reach up to 0.90 at 873 K in the BiCuSeO oxyselenides by the 10% Zn doping, which makes Zn‐doped BiCuSeO to be a promising candidate for thermoelectric applications.