Thermoelectric properties of transition-metal oxide NaCo2O4 system

被引：86

作者：

Yakabe, H ^{[1
]}

Kikuchi, K ^{[1
]}

Terasaki, I ^{[1
]}

Sasago, Y ^{[1
]}

Uchinokura, K ^{[1
]}

机构：

[1] Tokyo Gas Co Ltd, Frontier Technol Res Inst, Yokohama, Kanagawa 230, Japan

来源：

PROCEEDINGS ICT'97 - XVI INTERNATIONAL CONFERENCE ON THERMOELECTRICS | 1997年

关键词：

D O I：

10.1109/ICT.1997.667584

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

A transition-metal oxide NaCo2O4 system has been synthesized by a standard solid-state reaction method, and the thermoelectric properties have been measured. The resistivity rho and the thermoelectric power alpha of the as-sintered NaCo2O4 is 2 m Omega cm and 100 mu V/K at room temperature, respectively. By hot-pressing, the electrical resistivity is reduced to about 60%, and by Ba- or Bi-substitution for Na, Cu- or Bi-substitution for Co, the thermoelectric power is enhanced up to 1.4 times. For all the samples, the figure-of-merit shows a flat temperature dependence over a wide range from 100 to 400 degrees C, and in the hot-pressed Na(Co0.95Cu0.05)(2)O-4, the maximum value of 0.88 x 10(-3) K-1 is achieved around 300 degrees C, with rho=2 m Omega cm, alpha=147 mu V/K, and the thermal conductivity kappa=1.3 W/mK. In spite of a low carrier mobility material, NaCo2O4 system shows good thermoelectric performance. This indicates a possibility of applying low-mobility materials to thermoelectric devices, and thus NaCo2O4 system will be a prospective candidate for thermoelectric materials.

引用

页码：523 / 527

页数：5