Cation distribution in the Bi{sub 4-x}RE{sub x}Ti{sub 3}O{sub 12} (RE = La, Nd) solid solution and Curie temperature dependence

Journal Article · Sun Mar 15 00:00:00 EDT 2009 · Materials Characterization

DOI:https://doi.org/10.1016/j.matchar.2008.09.003· OSTI ID:21192606

Villafuerte-Castrejon, M E; Gonzalez, F ^[1]; Bucio, L ^[2]; Novelo-Peralta, O ^[1]; Sato-Berru, R Y; Ocotlan-Flores, J ^[3]

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1. Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, A.P. 70-360, 04510 Mexico D. F. (Mexico)
2. Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, A.P. 20-364, 01000 Mexico D. F. (Mexico)
3. Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, AP 70-186, Mexico D. F (Mexico)

Bi{sub 4-x}RE{sub x}Ti{sub 3}O{sub 12} (RE = La, Nd) ferroelectric powders were prepared by a co-precipitation route. Raman spectroscopy and X-ray diffraction were employed to determine the crystal site of La{sup 3+} and Nd{sup 3+} as well as the effect of their addition on the crystal structure. It was found that La atoms were not only placed preferentially in pseudo-perovskite A sites for concentrations x {<=} 1.2 but also substituted for Bi{sup 3+} in (Bi{sub 2}O{sub 2}){sup 2+} layers for greater concentrations. A similar behavior was observed with the limit value x = 0.8 in case of Nd{sup 3+}. In solid solution La or Nd{sup 3+} ions diminish the distortions in the octahedron formed by oxygen atoms, so there is a tendency to undergo a transition in crystal symmetry from orthorhombic to tetragonal. Finally differential scanning calorimetry (DSC) shows a linear dependence of the Curie temperature (T{sub c}) when the amount of La{sup 3+} or Nd{sup 3+} was increased.

• OSTI ID: 21192606
• Journal Information: Materials Characterization, Vol. 60, Issue 3; Other Information: DOI: 10.1016/j.matchar.2008.09.003; PII: S1044-5803(08)00247-7; Copyright (c) 2008 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BISMUTH COMPOUNDS
BISMUTH IONS
CALORIMETRY
CATIONS
COPRECIPITATION
CRYSTALS
CURIE POINT
FERROELECTRIC MATERIALS
LANTHANUM COMPOUNDS
LANTHANUM IONS
LAYERS
NEODYMIUM COMPOUNDS
NEODYMIUM IONS
ORTHORHOMBIC LATTICES
OXIDES
PEROVSKITE
RAMAN SPECTROSCOPY
SOLID SOLUTIONS
TETRAGONAL LATTICES
TITANIUM COMPOUNDS
X-RAY DIFFRACTION