Original scientific paper

Formation and Characterization of NiFe₂O₄

Svetozar Musić ; Ruder Bošković Institute, P. O. Box 1016, 10001 Zagreb, Croatia
Davor Balzar ; Ruder Bošković Institute, P. O. Box 1016, 10001 Zagreb, Croatia
Stanko Popović ; Ruder Bošković Institute, P. O. Box 1016, 10001 Zagreb, Croatia
Marijan Gotić ; Ruder Bošković Institute, P. O. Box 1016, 10001 Zagreb, Croatia
Ilona Czako-Nagy ; "Department of Nuclear Chemistry, Eotoos Lorand University, p. O. Box 32, 1518 Budapest, Hungary
Samet Dalipi ; Ruder Bošković Institute, P. O. Box 1016, 10001 Zagreb, Croatia

Abstract

Synthesis of nickel ferrite, NiFe204, was performed applying the
thermal treatment of the corresponding mixed metal hydroxides or
the solid state reaction between NiO and a-Fe203. The samples
were studied by X-ray diffraction, Fourier transform IR spectroscopy
and 57Fe Mčssbauer spectroscopy. Ball-milling of NiFe204
caused a decrease of hyperfine magnetic fields corresponding to
Fe3+ ions in tetrahedral and octahedral sites, an increase of the
Mossbauer spectral line widths, as well as a slight increase of isomer
shifts. It was supposed that the ball-milling of NiFe204 had
more influence on the degree of inversion than on other structural
properties of the spinel. It was found that the heating temperature,
and not the heating time, had the ultimate effect on NiFe204 microstructure. Samples heated up to 500 °C showed a pronounced
size-correlated diffraction line broadening, corresponding to the coherent domain size of about 13 nm, and rather small crystalline
disorder. Samples heated at temperature s above "" 1000 °C had
much larger crystallites, exhibiting very small disorder.

Keywords

Hrčak ID:

176969

URI

https://hrcak.srce.hr/176969

Publication date:

1.5.1997.

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