Anisotropic Thermal and Chemical Expansion in Sr-Substituted LaMnO3+δ: Implications for Chemical Strain Relaxation

被引:73
作者
Grande, Tor [1 ]
Tolchard, Julian R. [1 ]
Selbach, Sverre M. [1 ]
机构
[1] Norwegian Univ Sci & Technol, Dept Mat Sci & Engn, NO-7491 Trondheim, Norway
关键词
perovskite; point defects; thermal expansion; chemical expansion; chemical strain relaxation; YTTRIA-STABILIZED ZIRCONIA; LANTHANUM MANGANITE; DEFECT CHEMISTRY; MECHANICAL-PROPERTIES; OXYGEN-STOICHIOMETRY; ELECTRONIC-STRUCTURE; CRYSTAL-STRUCTURE; PHASE-DIAGRAM; PEROVSKITE; DIFFUSION;
D O I
10.1021/cm2030608
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
The anisotropic thermal and chemical expansion of rhombohedral (R (3) over barc) La1-xSrxMnO3+delta (x = 0.2, 0.3) was investigated by in situ high temperature X-ray diffraction of submicrometer size powders in pure oxygen and nitrogen (inert) atmospheres. The thermal expansion of the long axis c was found to be close to twice as high as the thermal expansion of the short axis a. The large thermal expansion of the c-axis is caused by rectification of the antiferrodistortive tilting and decompression of the MnO6/2 octahedra. The unit cell parameters were shown to be strongly dependent on the partial pressure of oxygen, which was attributed to chemical expansion/contraction due to reduction/oxidation of Mn. Anisotropic chemical expansion/contraction was more pronounced for the unit cell parameter a than for c, and the chemical expansion/contraction was inferred to reflect the size of the MnO6/2 octahedra. The onset of chemical expansion in nitrogen and contraction in oxygen atmosphere during heating was discussed in terms of a gradual transformation from a nonequilibrium to an equilibrium point defect population in La1-xSrxMnO3+delta. Possible implications of slow relaxation of chemically induced stresses at the nanoscale and in epitaxial thin films are addressed. Finally, a second order phase transition from the ferroelastic (R (3) over barc) to paraelastic state (Pm (3) over barm) is reported for La0.7Sr0.3MnO3+delta at 850 +/- 25 degrees C. The temperature of the phase transition decreases with increasing Sr content in La1-xSrxMnO3+delta.
引用
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页码:338 / 345
页数:8
相关论文
共 71 条
[1]  
Adler SB, 2001, J AM CERAM SOC, V84, P2117, DOI 10.1111/j.1151-2916.2001.tb00968.x
[2]   A manometric method for the determination of chemical diffusion in perovskite-type cathode materials of the solid oxide fuel cell [J].
Badwal, SPS ;
Jiang, SP ;
Love, J ;
Nowotny, J ;
Rekas, M ;
Vance, ER .
CERAMICS INTERNATIONAL, 2001, 27 (04) :431-441
[3]   Chemical diffusion in perovskite cathodes of solid oxide fuel cells:: the Sr doped LaMn1-xMxO3 (M=Co, Fe) systems [J].
Badwal, SPS ;
Jiang, SP ;
Love, J ;
Nowotny, J ;
Rekas, M ;
Vance, ER .
CERAMICS INTERNATIONAL, 2001, 27 (04) :419-429
[4]   Oxygen tracer diffusion in undoped lanthanum manganites [J].
Berenov, AV ;
MacManus-Driscoll, JL ;
Kilner, JA .
SOLID STATE IONICS, 1999, 122 (1-4) :41-49
[5]   Thermal and chemical expansion of Sr-doped lanthanum cobalt oxide (La1-xSrxCoO3-δ) [J].
Chen, XY ;
Yu, JS ;
Adler, SB .
CHEMISTRY OF MATERIALS, 2005, 17 (17) :4537-4546
[6]   Structural and magnetic phase diagrams of La1-xSrxMnO3 and Pr1-ySryMnO3 -: art. no. 094431 [J].
Chmaissem, O ;
Dabrowski, B ;
Kolesnik, S ;
Mais, J ;
Jorgensen, JD ;
Short, S .
PHYSICAL REVIEW B, 2003, 67 (09)
[7]  
Coelho A.A., 2004, TOPAS ACAD GEN PROFI
[8]   Structure-properties phase diagram for La1-xSrxMnO3 (0.1≤x≤0.2) [J].
Dabrowski, B ;
Xiong, X ;
Bukowski, Z ;
Dybzinski, R ;
Klamut, PW ;
Siewenie, JE ;
Chmaissem, O ;
Shaffer, J ;
Kimball, CW ;
Jorgensen, JD ;
Short, S .
PHYSICAL REVIEW B, 1999, 60 (10) :7006-7017
[9]   Oxygen transport in La1-xSrxMn1-yCoyO3±δ perovskites -: Part I.: Oxygen tracer diffusion [J].
De Souza, RA ;
Kilner, JA .
SOLID STATE IONICS, 1998, 106 (3-4) :175-187
[10]   Epitaxial Strain-Induced Chemical Ordering in La0.5Sr0.5CoO3-δ Films on SrTiO3 [J].
Donner, Wolfgang ;
Chen, Chonglin ;
Liu, Ming ;
Jacobson, Allan J. ;
Lee, Yueh-Lin ;
Gadre, Milind ;
Morgan, Dane .
CHEMISTRY OF MATERIALS, 2011, 23 (04) :984-988