Seebeck Coefficient of Ca1-x Pr x MnO3-δ Paramagnetic Manganites

被引：11

作者：

Leonidov, I. A. ^{[1
]}

Konstantinova, E. I. ^{[1
]}

Patrakeev, M. V. ^{[1
]}

Markov, A. A. ^{[1
]}

Kozhevnikov, V. L. ^{[1
]}

机构：

[1] Russian Acad Sci, Ural Branch, Inst Solid State Chem, Pervomaiskaya Ul 91, Ekaterinburg 620990, Russia

来源：

INORGANIC MATERIALS | 2017年 / 53卷 / 06期

基金：

俄罗斯科学基金会;

关键词：

perovskite-like oxides; CaMnO3 calcium manganite; small polarons; Seebeck coefficient; thermoelectricity; MAGNETIC PHASE-DIAGRAMS; TRANSPORT; NONSTOICHIOMETRY; THERMOPOWER;

D O I：

10.1134/S0020168517060097

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The Seebeck coefficient (S) of Ca-1 xPrxMnO3 (delta) (x = 0, 0.05, 0.10, 0.15) manganites with a perovskite-like structure has been measured in air at temperatures (T) from 300 to 1200 K. The negative sign of their S indicates that all of the samples have n-type conductivity. The observed increase in the magnitude of the Seebeck coefficient with increasing T is interpreted in terms of small-polaron transport with allowance for the decrease in Mn3+ concentration as a result of the disproportionation reaction 2Mn(3+) = Mn2+ + Mn4+. Based on a theoretical analysis of experimental S(T) data, we calculated equilibrium constants for the disproportionation reaction, carrier concentration, and the concentration of sites available for carrier migration as functions of temperature. It has been shown that, for an adequate analysis of electron hopping and calculation of the Seebeck coefficient of the electron-doped manganites, the spin state of the Mn4+ ions should be taken into account.

引用

页码：583 / 588

页数：6

共 18 条

[1] SMALL-POLARON VERSUS BAND CONDUCTION IN SOME TRANSITION-METAL OXIDES [J].