INTECIN   20395
INSTITUTO DE TECNOLOGIAS Y CIENCIAS DE LA INGENIERIA "HILARIO FERNANDEZ LONG"
Unidad Ejecutora - UE
artículos
Título:
Structural and Magnetic Properties of Zn Doped Magnetite Nanoparticles Obtained by Wet Chemical Method
Autor/es:
SERGIO FERRARI; F. D. SACCONE; J.C. APHESTEGUY
Revista:
IEEE TRANSACTIONS ON MAGNETICS
Editorial:
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Referencias:
Lugar: New York; Año: 2015 vol. 51 p. 1 - 6
ISSN:
0018-9464
Resumen:
The structural and magnetic properties of Fe_(3-x)Zn_xO_4 (x : 0, 0.1, 0.2, 0.5, 1) nanoparticles, prepared by wet chemical method, have been studied by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Mössbauer spectroscopy and magnetization measurements. The nanoparticles are polyhedrical -shaped with a narrow distribution in size as it was verified by SEM. By Rietveld analysis of X-ray diffraction patterns, it was determined that the cristallytes sizes of Fe_(3-x)Zn_xO_4 in spinel structure is in the range of 30 to 50 nm. Hysteresis cycles, measured at different temperatures (300, 200, 100, 50 and 7 K), showed an increase in saturation while temperature is diminished, as it is expected. All samples, exhibited a high blocking temperature of about 350 K, as it was determined by ZFC-FC measurements. This fact, reveals their strongly interacting superparamagnetic nature. Real AC susceptibility increases with temperature while the imaginary part have a maximum which depends on frequency, and it is related to a critical temperature which depends on composition. A Neel-Arrhenius dependence of frequency on the critical temperature was found for all the samples. We determined a minimum of the effective anisotropy for x=0.2.