The effect of element substitution on high-temperature thermoelectric properties of Ca3CO2O6 compounds
The effect of element substitution on high-temperature thermoelectric properties of Ca3CO2O6 compounds
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DOI：
10.1016/j.jssc.2005.03.004
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发表时间：
2005-05-01
影响因子：
3.3
通讯作者：
Funahashi, R
中科院分区：
文献类型：
--
作者：
Mikami, M;Funahashi, R
采用固相反应合成了多晶Ca3CO1.8M0.2O6（M=Mn、Fe、Co、Ni、Cu）和Ca2.7Na0.3Co2O6，以评价取代对Ca3CO2O6热电性能的影响。考虑到电阻率 (rho) 和塞贝克系数 (S) 同时降低，Mn、Cu 和 Na 的取代似乎增加了载流子密度。相反，Fe 取代似乎会降低载流子密度，导致 S 和 rho 同时增加。由于晶粒尺寸和晶界连通性的增强，Cu 和 Na 的替代导致 rho 显着降低，这可能对 rho 产生强烈影响。不仅电子态的固有取代效应，而且微观结构的这种改变在热电功率因数的提高中发挥着重要作用，特别是在钠取代样品的情况下。 (c) 2005 Elsevier Inc. 保留所有权利。
Polycrystalline Ca3CO1.8M0.2O6 (M= Mn, Fe, Co, Ni, Cu) and Ca2.7Na0.3Co2O6 were synthesized by solid-state reaction to evaluate the effect of substitution on the thermoelectric properties of Ca3CO2O6. Substitution by Mn, Cu and Na appears to increase carrier density, given that electrical resistivity (rho) and the Seebeck coefficient (S) were simultaneously reduced. Conversely, Fe substitution seems to reduce carrier density, resulting in a simultaneous increase in S and rho. Cu and Na substitution resulted in a significant decrease in rho due to enhancement of grain size and grain boundary connectivity, which could have a strong impact on rho. Not only the intrinsic substitution effect on the electronic state but also this modification of the microstructure plays an important role in improvement of the thermoelectric power factor, particularly in the case of the Na-substituted sample. (c) 2005 Elsevier Inc. All rights reserved.