SUBSTITUTED IRON OXIDES FOR THE GRANT ENTITLED LASER PROCESSING OF ADVANCED MAGNETIC MATERIALS

Technical Report · Mon Mar 01 04:00:00 EST 2004

DOI:https://doi.org/10.2172/822034· OSTI ID:822034

Sorescu, Monica

Structural and morphological characteristics of (1-x){alpha}-Fe{sub 2}O{sub 3}-xSnO{sub 2} (x = 0.0-1.0) nanoparticles obtained under hydrothermal conditions have been investigated by X-ray diffraction (XRD), transmission Moessbauer spectroscopy, scanning (SEM) and transmission electron microscopy (TEM) as well as energy dispersive X-ray analysis (EDX). On the basis of the Rietveld structure refinements of the XRD spectra at low tin concentrations, it was found that Sn{sup 4+} ions partially substitute for Fe{sup 3+} at the octahedral sites and also occupy the interstitial octahedral sites which are vacant in {alpha}-Fe{sub 2}O{sub 3} corundum structure. A phase separation of {alpha}-Fe{sub 2}O{sub 3} and SnO{sub 2} was observed for x {ge} 0.4: the {alpha}-Fe{sub 2}O{sub 3} structure containing tin decreases simultaneously with the increase of the SnO{sub 2} phase containing substitutional iron ions. The mean particle dimension decreases from 70 nm to 6 nm, as the molar fraction x increases up to x = 1.0. The estimated solubility limits in the nanoparticle system (1-x){alpha}-Fe{sub 2}O{sub 3}-xSnO{sub 2} synthesized under hydrothermal conditions are: x {le} 0.2 for Sn{sup 4+} in {alpha}-Fe{sub 2}O{sub 3} and x {ge} 0.7 for Fe{sup 3+} in SnO{sub 2}. These findings are in press in the Journal of Physics and Chemistry of Solids.

• Research Organization: Duquesne University (US)
• Sponsoring Organization: (US)
• DOE Contract Number: FG26-02NT41595
• OSTI ID: 822034
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
CHEMISTRY
CORUNDUM
DIMENSIONS
INTERSTITIALS
IRON IONS
IRON OXIDES
LASERS
MAGNETIC MATERIALS
MOESSBAUER EFFECT
PHYSICS
PROCESSING
SOLUBILITY
SPECTRA
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION