Nanosized ceria-based ceramics: a comparative study

被引：29

作者：

Singh, K.

Acharya, S. A. ^{[1
]}

Bhoga, S. S.

机构：

[1] Jawaharlal Darda Inst Engn & Technol, Dept Phys, Yavatmal 445001, MS, India

[2] Amaravati Univ, Dept Phys, Amaravati, India

[3] Nagpur Univ, Dept Phys, Nagpur 440010, Maharashtra, India

来源：

IONICS | 2006年 / 12卷 / 4-5期

关键词：

ceria electrolytes; combustion synthesis; electrical conductivity; bond ionicity; configurational and thermal entropy;

D O I：

10.1007/s11581-006-0050-2

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Ce(1-x)Gd/SmxO2-delta (x=0.05-0.2, GDC/SDC) nanometric powder was prepared by glycine-nitrates combustion synthesis, by strictly following uniformity in the preparation route. The thermochemical properties of the obtained precursor were studied by TGA/DTA. Crystallization of the fluorite phase occurred on heating at 800 degrees C or higher temperature. The grain size of calcined powder was found to be about 15 nm. Densification was studied as a function of dopant content. SDC was found more sinterable than GDC. Crystal structure and microstructure were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Electrical characterization was carried out using the impedance spectroscopy method in the frequency range of 50 Hz-13 MHz. The bulk conductivity of SDC is higher than GDC pellet for all concentration ranges. The results were analyzed by using the concept of change of the chemical bond ionicity due to the replacement of the host by dopant. Guest/host ionic size, valence mismatch ratio and their consequences are counted semi-quantitatively into the configurational and thermal entropy.

引用

页码：295 / 301

页数：7

共 23 条

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ADHAM KE, 1983, SOLID STATE IONICS, V9, P905

[2]

Anderson R. G., 1981, SOLID STATE IONICS, V5, P547

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