Simultaneous optimization of the overall thermoelectric properties of Cu3SbSe4 by band engineering and phonon blocking
Simultaneous optimization of the overall thermoelectric properties of Cu3SbSe4 by band engineering and phonon blocking
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通过能带工程和声子阻挡同时优化 Cu3SbSe4 的整体热电性能
DOI：
10.1016/j.jallcom.2017.06.347
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发表时间：
2017-11-15
影响因子：
6.2
通讯作者：
Hou, Jingdi
中科院分区：
文献类型：
--
作者：
Zhang, Dan;Yang, Junyou;Hou, Jingdi
同时优化热电材料的电学和热学耦合输运特性是一个挑战。在这里，通过Te替代证明了Cu3SbSe_4的整体热电性能的提高。结果表明，Te掺杂实现了Seebeck系数、电导率和热导率的同时优化，与未掺杂的Cu3SbSe4相比，在整个温度范围内ZT值都有较大的提高。在Te掺杂的Cu3SbSe4体系中，由于禁带宽度变窄，导致了电阻率的降低；Seebeck系数的增大是由于费米能级附近态密度的增加；而热导率的降低则与点缺陷散射或化学键相互作用软化引入的声子阻塞有关。这项工作也为其他热电材料等价掺入重元素来提高整体热电性能提供了参考途径。(C)2017爱思唯尔B.V.保留所有权利。
It is a challenge to optimize the coupled electrical and thermal transport properties of a thermoelectric material simultaneously. Here, the enhancement of overall thermoelectric properties in Cu3SbSe4 has been demonstrated through Te substitution. The results display that the simultaneous optimization of the Seebeck coefficient, electrical conductivity and thermal conductivity is realized after Te-doping and thus yielding considerable enhancements in ZT values in the whole temperature range as comparison to that of pristine Cu3SbSe4. In Te-doped Cu3SbSe4 system, the reduction of electrical resistivity is due to the narrowed bandgap; the enhanced Seebeck coefficient stems from the increased density of states near the Fermi level; and the suppressed thermal conductivity is related to the introduced phonon blocking from point defect scattering or softening of chemical bond interaction. This work can also offer a referential route to boost the overall thermoelectric properties by isovalent doping with heavy element for other thermoelectric materials. (C) 2017 Elsevier B.V. All rights reserved.