Preparation and fluorite-pyrochlore phase transformation in Gd2Zr2O7

被引：83

作者：

Lee, Y. H. ^{[1
]}

Sheu, H. S. ^{[2
]}

Deng, J. P. ^{[1
]}

Kao, H. -C. I. ^{[1
]}

机构：

[1] Tamkang Univ, Dept Chem, Tamsui 25137, Taiwan

[2] Natl Synchrotron Radiat Res Ctr, Hsinchu 30076, Taiwan

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2009年 / 487卷 / 1-2期

关键词：

Oxide materials; Chemical synthesis; Crystal structure; Phase transitions; TEM; FUEL-CELL MATERIALS; DISORDER; CONDUCTIVITY; TEMPERATURE; DIFFUSION; OXIDES;

D O I：

10.1016/j.jallcom.2009.08.021

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：

Gd2Zr2O7 prepared by a polymeric citrate precursor method has a defect fluorite phase if it is calcined in static air between 700 and 1200 degrees C; it has a disordered pyrochlore phase, if the sample is heat treated at 1300 or 1400 degrees C. Phase transformation is accelerated by increasing the preparation temperature and heat treatment period. Sample prepared at 1400 degrees C is more ordered than the one calcined at 1300 degrees C. Unit cell a-axis dimension of the pyrochlore phase is slightly longer than the 2a of the fluorite phase. Expansion of the unit cell is probably due to the different distribution of the oxygen atoms in these two phases and the quenched process. Particle size analysis on the maximum intense XRD peak by the Scherrer formula is in the range of 6-68 nm, grain grows with increasing the preparation temperature and prolonged heat treatment time. (C) 2009 Elsevier B.V. All rights reserved.

引用

页码：595 / 598

页数：4

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