Effect of 20% Cr-doping on structural and electrical properties of La0.67Ca0.33MnO3 perovskite

被引：6

作者：

Dhahri, Abdessalem ^{[1
,2
]}

Hcini, Sobhi ^{[3
,4
]}

Omri, Aref ^{[3
]}

Bouazizi, Lamjed ^{[5
]}

机构：

[1] Univ Monastir, Fac Sci Monastir, Dept Phys, Lab Phys Chem Mat, Monastir 5019, Tunisia

[2] Umm Al Qura Univ, Al Qunfudah Univ Coll, Mecca, Saudi Arabia

[3] Univ Kairouan, Res Unit Valorizat & Optimizat Exploitat Resource, Fac Sci & Technol Sidi Bouzid, Univ Campus Agr City, Sidi Bouzid 9100, Tunisia

[4] Univ Gafsa, Fac Sci Gafsa, Dept Phys, Univ Campus Sidi Ahmed Zarroug, Gafsa 2112, Tunisia

[5] Prince Sattam Bin Abdulaziz Univ, Coll Engn, Al Kharj 11942, Saudi Arabia

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2016年 / 687卷

关键词：

Perovskites; Rietveld analysis; Complex impedance spectroscopy; Relaxation time; Electrical equivalent circuit; Conductance; TRANSPORT-PROPERTIES; IMPEDANCE SPECTROSCOPY; CRITICAL-BEHAVIOR; MN; MAGNETORESISTANCE; TEMPERATURE; RESISTIVITY; RELAXATION;

D O I：

10.1016/j.jallcom.2016.06.140

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：

Structural and electrical properties of La0.67Ca0.33Mn1-xCrxO3 (x = 0 and 0.2) manganites are studied in this work. The samples were prepared using Pechini sol-gel method at 1173 K. Rietveld analysis of X-ray diffraction (XRD) patterns shows the formation of pure crystalline phase with orthorhombic Pnma structure with a decrease of the unit cell volume and crystalline domain size when increasing Cr-content. Electrical properties of the samples have been investigated using complex impedance analysis in 180 320 K temperature range with varying frequency between 40 and 10(6) Hz. For both samples, frequency dependence of imaginary part of impedance (Z '') shows the existence of relaxation phenomenon. The impedance study using Nyquist representation revealed the appearance of semicircle arcs and an equivalent circuit of the type of R-1 + (R-2//Z(CPE)) has been proposed to explain the impedance results. The conductance curves were analyzed by Jonscher power law and the deduced activation energy values are close to those calculated from relaxation time indicating that relaxation process and conductivity have the same origin. (C) 2016 Elsevier B.V. All rights reserved.

引用

页码：521 / 528

页数：8

共 44 条

[1] Development of new materials for spintronics [J].