Structural and magnetic properties of ZnO–CoFe2O4 nanocomposites

Autor: F. Nakagomi, Natalia da Silva Moura, T.J. Castro, Paulo C. Morais, S.W. da Silva, Adolfo Franco
Rok vydání: 2015
Předmět:
Zdroj: Journal of Magnetism and Magnetic Materials. 389:27-33
ISSN: 0304-8853
DOI: 10.1016/j.jmmm.2015.04.036
Popis: Nanocomposites with chemical composition (CoFe2O4)x+(ZnO)1–x were prepared by the combustion reaction method. X-ray diffraction data reveal the presence of only two crystalline nanosized phases with average diameters of ~55 nm (ZnO) and ~60 nm (CoFe2O4). The Rietveld method revealed that the molar ratio between the two phases shifted their nominal values from x=0.005, 0.050, 0.100, 0.200 and 0.400 up to x=0.030, 0.090, 0.170, 0.270 and 0.570, respectively. It was also found that the change of the lattice parameters of the wurtzite and spinel phases is related with the exchange of metallic ions between the two crystal structures. Our findings show that the ion exchange has direct influence on the vibrational and magnetic properties of the as-produced nanocomposites. Evidences supporting our findings are the appearance of vibrational modes induced by disorder and the decrease of the saturation magnetization.
Databáze: OpenAIRE