Mechanosynthesis and magnetic properties of nanocrystalline LaFeO{sub 3} using different iron oxides

Journal Article · Wed May 06 00:00:00 EDT 2009 · Materials Research Bulletin

DOI:https://doi.org/10.1016/j.materresbull.2008.11.015· OSTI ID:21199760

Botta, P M ^[1]; Bercoff, P G ^[2]; Porto Lopez, J M ^[1]

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1. Instituto de Investigaciones en Ciencia y Tecnologia de Materiales, INTEMA (CONICET-UNMdP), J.B. Justo Avenue 4302, (B7608FDQ) Mar del Plata, Buenos Aires (Argentina)
2. Facultad de Matematica, Astronomia y Fisica, FaMAF (UNC), CONICET, Ciudad Universitaria, (5000) Cordoba (Argentina)

The synthesis of the orthoferrite LaFeO{sub 3} using high-energy ball-milling of La{sub 2}O{sub 3} and Fe{sub 3}O{sub 4} or {alpha}-Fe{sub 2}O{sub 3} oxides and subsequent thermal treatments of resulting powders was studied. The phase evolution during the mechanical treatment was analyzed by X-ray diffraction (XRD), differential thermal analysis (DTA) and scanning electron microscopy (SEM). Also, magnetic properties of the obtained materials were measured at room temperature by vibrating sample magnetometry (VSM). From 30 min of mechanochemical activation the gradual disappearance of reactants and the formation of LaFeO{sub 3} were observed. For both reactive mixtures the reaction was completed after 3 h of milling. Magnetic hysteresis loops of these mechanoactivated samples showed a significant ferromagnetic component in LaFeO{sub 3}. This behavior was interpreted on the basis of a spin-canting effect induced by the mechanochemical treatment. Thermal treatments allowed the relaxation of the distorted structure, resulting in the formation of the conventional antiferromagnetic LaFeO{sub 3} phase.

• OSTI ID: 21199760
• Journal Information: Materials Research Bulletin, Vol. 44, Issue 5; Other Information: DOI: 10.1016/j.materresbull.2008.11.015; PII: S0025-5408(08)00382-6; Copyright (c) 2008 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANTIFERROMAGNETISM
COMMINUTION
CRYSTALS
DIFFERENTIAL THERMAL ANALYSIS
HEAT TREATMENTS
HYSTERESIS
IRON OXIDES
LANTHANUM OXIDES
MAGNETIC PROPERTIES
NANOSTRUCTURES
SCANNING ELECTRON MICROSCOPY
SYNTHESIS
TEMPERATURE RANGE 0273-0400 K
VIBRATING SAMPLE MAGNETOMETERS
X-RAY DIFFRACTION