Pyrochlore type semiconducting ceramic oxides in Ca-Ce-Ti-M-O system (M = Nb or Ta)-Structure, microstructure and electrical properties

被引：38

作者：

Deepa, M. ^{[1
]}

Rao, P. Prabhakar ^{[1
]}

Radhakrishnan, A. N. ^{[1
]}

Sibi, K. S. ^{[1
]}

Koshy, Peter ^{[1
]}

机构：

[1] NIIST, Mat & Minerals Div, Trivandrum 695019, Kerala, India

来源：

MATERIALS RESEARCH BULLETIN | 2009年 / 44卷 / 07期

关键词：

Oxides; Semiconductors; X-ray diffraction; Raman spectroscopy; Electron microscopy; Electrical properties; FT-IR SPECTRA; SM; GD; SPECTROSCOPY; CONDUCTORS; RAMAN;

D O I：

10.1016/j.materresbull.2009.02.014

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

A new series of pyrochlore type ceramic semiconducting oxides in Ca-Ce-Ti-M-O (M = Nb or Ta) system has been synthesized by the conventional ceramic route. The electrical conductivity measurements show that these oxides exhibit semiconducting behavior and the conductivity increases with the Ce content in the compound. Activation energy of the current carriers is in the range of 0.5-1.6 eV. The electrical conductivity in these oxides is due to the presence of Ce3+, which remains in the reduced state without being oxidized to Ce4+ by structural stabilization. The photoluminescence and X-ray photoelectron spectroscopy analysis corroborate the presence of Ce in the 3+ state. Impedance spectral analysis is carried out to evaluate the transport properties and indicates that the conduction in these compounds is mainly due to electronic contribution. The X-ray powder diffraction and Raman spectroscopy analysis establishes that these oxides belong to a cubic pyrochlore type Structure. (c) 2009 Elsevier Ltd. All rights reserved.

引用

页码：1481 / 1488

页数：8

共 33 条

[1] NTC characteristics of bismuth based ceramic at high temperature [J].

Basu, A ;

Brinkman, AW ;

Hashemi, T .

INTERNATIONAL JOURNAL OF INORGANIC MATERIALS, 2001, 3 (08) :1219-1221

[2] Microstructure and electrical properties of Ni-Zn manganite ceramics [J].

Chanel, C ;

Guillemet-Fritsch, S ;

Sarrias, J ;

Rousset, A .

INTERNATIONAL JOURNAL OF INORGANIC MATERIALS, 2000, 2 (2-3) :241-247

[3] Solid state ceramic gas sensors based on interfacing ionic conductors with semiconducting oxides [J].

Di Bartolomeo, E ;

Traversa, E ;

Baroncini, M ;

Kotzeva, V ;

Kumar, RV .

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, 2000, 20 (16) :2691-2699

[4]

Du HL, 2004, J MATER SCI-MATER EL, V15, P613

[5] Preparation, electronic structure, and photoluminescence properties of Eu2+ and Ce3+/Li+-activated alkaline earth silicon nitride MSiN2 (M = Sr, Ba) [J].

Duan, C. J. ;

Wang, X. J. ;

Otten, W. M. ;

Delsing, A. C. A. ;

Zhao, J. T. ;

Hintzen, H. T. .

CHEMISTRY OF MATERIALS, 2008, 20 (04) :1597-1605

[6]

Glerup M, 2001, J SOLID STATE CHEM, V160, P25, DOI 10.1006/jssc.2001.9142

[7] Spectroscopic investigations of the structural phase transition in Gd2(Ti1-yZry)2O7 pyrochlores [J].

Hess, NJ ;

Begg, BD ;

Conradson, SD ;

McCready, DE ;

Gassman, PL ;

Weber, WJ .

JOURNAL OF PHYSICAL CHEMISTRY B, 2002, 106 (18) :4663-4677

[8] High temperature NTC ceramic resistors (ambient-1000°C) [J].

Houivet, D ;

Bernard, J ;

Haussonne, JM .

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, 2004, 24 (06) :1237-1241

[9] Synthesis and characterization of reduced niobates CaLnNb(2)O(7), Ln=Y, Nd with a pyrochlore structure [J].

Istomin, SY ;

Dyachenko, OG ;

Antipov, EV ;

Svensson, G .

MATERIALS RESEARCH BULLETIN, 1997, 32 (04) :421-430

[10] UNIVERSAL DIELECTRIC RESPONSE [J].

JONSCHER, AK .

NATURE, 1977, 267 (5613) :673-679

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