Oxygen ion conductivity of hexagonal La2W1.25O6.75

被引：23

作者：

Kovalevsky, AV ^{[1
]}

Kharton, VV ^{[1
]}

Naumovich, EN ^{[1
]}

机构：

[1] Belarusian State Univ, Inst Physicochem Problems, Minsk 220080, BELARUS

来源：

MATERIALS LETTERS | 1999年 / 38卷 / 04期

关键词：

lanthanum-tungsten oxide; oxygen ionic conductivity; transference numbers; thermal expansion;

D O I：

10.1016/S0167-577X(98)00178-5

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Mixed oxygen ionic and electronic conduction was found for hexagonal lanthanum-tungsten oxide, La2W1.25O6.75, at temperatures of 900-1450 K. In atmospheric air, the partial ionic conductivity was established to prevail electronic conductivity and to be 1.3 x 10(-4) S/cm at 1170 K. Ion transference numbers were determined by Faradaic efficiency measurements to be 0.92 +/- 0.01 in air at 1170 - 1300 K. Decreasing oxygen partial pressure leads to increasing electronic conductivity due to leaving oxygen from the crystal lattice of La2W1.25O6.75. The activation energy for total electrical conductivity of the lanthanum-tungsten oxide in air is 113 +/- 2 kJ/mol. Mean thermal expansion coefficient of the La2W1.25O6.75 ceramics in the temperature range of 300 to 1100 K was calculated from the results of dilatometric studies to be (10.9 +/- 0.3) x 10(-6) K-1. (C) 1999 Elsevier Science B.V. All rights reserved.

引用

页码：300 / 304

页数：5

共 17 条

[1] Oxide ion conductivity in Bi(2)W(1-x)ME(x)O(6-x/2) (ME=Nb,Ta) [J].

Baux, N ;

Vannier, RN ;

Mairesse, G ;

Nowogrocki, G .

SOLID STATE IONICS, 1996, 91 (3-4) :243-248

[2]

Bouwmeester H., 1996, FUNDAMENTALS INORGAN

[3] CRYSTAL-CHEMISTRY, MODULATED STRUCTURE, AND ELECTRICAL-CONDUCTIVITY IN THE OXYGEN EXCESS SCHEELITE-BASED COMPOUNDS LA1-XTHXNBO4+X/2 AND LANB1-XWXO4+X/2 [J].

CAVA, RJ ;

ROTH, RS ;

NEGAS, T ;

PARKER, HS ;

MINOR, DB .

JOURNAL OF SOLID STATE CHEMISTRY, 1981, 40 (03) :318-329

[4] ANALYSIS OF DIELECTRIC PARAMETERS AND ION HOPPING RATES IN THE BETA-LNNB3O9 PHASES (LN = LA, CE, PR AND ND) [J].

HUANOSTA, A ;

ORGAZ, E .

SOLID STATE IONICS, 1993, 62 (1-2) :69-77

[5] OXIDE-ION CONDUCTION IN SOLID-SOLUTIONS LN(1-X)SR(X)COO(3-DELTA)(LN=LA,PR,ND) [J].

KHARTON, VV ;

NAUMOVICH, EN ;

VECHER, AA ;

NIKOLAEV, AV .

JOURNAL OF SOLID STATE CHEMISTRY, 1995, 120 (01) :128-136

[6] Mixed electronic and ionic conductivity of LaCo(M)O3 (M = Ga, Cr, Fe or Ni) I.: Oxygen transport in perovskites LaCoO3-LaGaO3 [J].

Kharton, VV ;

Viskup, AP ;

Naumovich, EN ;

Lapchuk, NM .

SOLID STATE IONICS, 1997, 104 (1-2) :67-78

[7] Formation and properties of reaction layers of cobaltite electrodes on bismuth oxide electrolytes [J].

Kharton, VV ;

Naumovich, EN ;

Samokhval, VV .

SOLID STATE IONICS, 1997, 99 (3-4) :269-280

[8]

Kinoshita K., 1992, Electrochemical Oxygen Technology

[9]

KONISHEVA EY, 1997, 1997 JOINT INT M EL, P2544

[10]

Kovalevskii AV, 1996, INORG MATER+, V32, P1230

← 1 2 →