Influence of the Mg-content on the cation distribution in cubic MgxFe3−xO4 nanoparticles

✍ Scribed by F. Nakagomi; S.W. da Silva; V.K. Garg; A.C. Oliveira; P.C. Morais; A. Franco Jr.

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 740 KB
• Volume: 182
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2009.06.036

✦ Synopsis

The influence of the Mg-content on the structural and magnetic properties of cubic Mg x Fe 3Àx O 4 nanoparticles prepared by combustion reaction was investigated using X-ray diffraction, transmission electron microscopy (TEM), M össbauer spectroscopy, and Raman spectroscopy. Lattice parameter, nanoparticle size, and cation (Mg 2+ , Fe 3+ ) distribution were quantified as a function of the Mg-content in the range 0.5rxr1.5. We found a mixed-like spinel structure at the smaller x-value end whereas the inverse-like spinel structure dominates samples with larger x-values. Moreover, in the x-value range investigated (0.5rxr1.5) we found no change in the quadrupole splitting and isomer shift values, though the hyperfine field decreases as the x-value increases. The splitting of the A 1g Raman mode was used to both quantify the Mg 2+ /Fe 3+ contents in the tetrahedral site and obtain the cation distribution in the Mg x Fe 3Àx O 4 structure. The cation distribution obtained from the Raman data is in very good agreement with the cation distribution obtained from the M össbauer data.