Phase transformations in the high-temperature form of pure and TiO2-stabilized Ta2O5

被引:21
作者
Brennecka, Geoff L.
Payne, David A.
Sarin, Pankaj
Zuo, J.-M.
Kriven, Waltraud M.
Hellwig, Holger
机构
[1] Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA
[2] Univ Illinois, Dept Geol, Urbana, IL 61801 USA
关键词
D O I
10.1111/j.1551-2916.2007.01790.x
中图分类号
TQ174 [陶瓷工业]; TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
The high-temperature forms of undoped tantalum pentoxide (H-100Ta(2)O(5)) and TiO2-modified Ta2O5 (H-92Ta(2)O(5)-8TiO(2)) were investigated by in situ synchrotron X-ray diffraction and Raman scattering measurements. Two unquenchable and reversible phase transformations were observed in pure H-Ta2O5, while only one was detected for TiO2-stabilized H-Ta2O5. Diffraction studies were consistent with displasive transformations, but hot-stage Raman spectroscopy indicated the existence of transient intermediate forms during the transformations. Use of complementary techniques enabled the reinterpretation of phase transformations in light of a newly proposed crystal structure model for H-Ta2O5, and emphasized the structural contributions of the oxygen sublattice.
引用
收藏
页码:2947 / 2953
页数:7
相关论文
共 30 条
[1]   Preparation of dense Ta2O5-based ceramics by a coated powder method for enhanced dielectric properties [J].
Brennecka, Geoff L. ;
Payne, David A. .
JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 2006, 89 (07) :2089-2095
[2]   ENHANCEMENT OF THE DIELECTRIC-CONSTANT OF TA2O5 THROUGH SUBSTITUTION WITH TIO2 [J].
CAVA, RF ;
PECK, WF ;
KRAJEWSKI, JJ .
NATURE, 1995, 377 (6546) :215-217
[3]   Supported tantalum oxide catalysts: Synthesis, physical characterization, and methanol oxidation chemical probe reaction [J].
Chen, YS ;
Fierro, JLG ;
Tanaka, T ;
Wachs, IE .
JOURNAL OF PHYSICAL CHEMISTRY B, 2003, 107 (22) :5243-5250
[4]   NONSTOICHIOMETRY AND MIXED CONDUCTION IN ALPHA-TA2O5 [J].
CHOI, GM ;
TULLER, HL .
JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 1990, 73 (06) :1700-1704
[5]   ALPHA-TA2O5 - AN INTRINSIC FAST OXYGEN ION CONDUCTOR [J].
CHOI, GM ;
TULLER, HL ;
HAGGERTY, JS .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1989, 136 (03) :835-838
[6]   Structural transformation in (Ta2O5)1-x(TiO2)x ceramics [J].
Dobal, PS ;
Katiyar, RS ;
Jiang, Y ;
Guo, R ;
Bhalla, AS .
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, 2000, 61 (11) :1805-1808
[7]   Micro-Raman scattering and x-ray diffraction studies of (Ta2O5)1-x(TiO2)x ceramics [J].
Dobal, PS ;
Katiyar, RS ;
Jiang, Y ;
Guo, R ;
Bhalla, AS .
JOURNAL OF APPLIED PHYSICS, 2000, 87 (12) :8688-8694
[8]   Processing and annealing conditions on the dielectric properties of (Ta2O5)0.92(TiO2)0.08 ceramics [J].
Guo, RY ;
Jiang, YJ ;
Bhalla, AS .
MATERIALS LETTERS, 2002, 57 (02) :270-274
[9]   ELECTRICAL-CONDUCTIVITY OF STABILIZED LOW AND HIGH-TEMPERATURE MODIFICATIONS OF TANTALUM PENTOXIDE (L-TA2O5 AND H-TA2O5) .2. ELECTRICAL-CONDUCTIVITY OF H-TA2O5 WITH ADDITIONS OF TIO2, HFO2 AND CR2O3 [J].
JOHANNESEN, O ;
KOFSTAD, P .
JOURNAL OF THE LESS-COMMON METALS, 1984, 99 (02) :187-204
[10]  
LAVES F, 1964, HELV PHYS ACTA, V37, P617