Síntese, caracterização e estudo das propriedades magnéticas do Zn1-xFexO (0,00 ≤ x ≤ 0,09) produzido por reação de combustão
Carregando...
Data
2010-11-25
Autores
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal de Goiás
Resumo
In this work compounds Zn1-xFexO, with 0.00 ≤ x ≤ 0.09, were synthesized by combustion reaction method with two different heating processes, in a thermal blanket and muffle furnace. Chemical analysis of compounds was performed by
atomic absorption spectroscopy (AAS) and Fourier transform infrared (FTIR). Structural analysis of the crystalline phase, the diameter of the crystallites and the lattice parameters were checked by X-ray diffraction (XRD, powder method)
and refinement software (Unitt and powder X cell). The analysis of surfaces and morphologies were determined by adsorption and desorption of N2 (ASAP, BET model) and transmission electron microscopy (TEM). Finally, Magnetic
measurements were performed by vibrating sample magnetometer (VSM). The stoichiometric determined by atomic absorption is in good agreement with the calculated value for all samples. The samples were synthesized in a thermal blanket which corresponds to the wurtzite crystal structure with no secondary phases. The samples synthesized in furnace had wurtzite crystal structure, however, showed a small sample to phase segregation above 5%. The second
phases are found with spinel phase indicate that the formation of zinc ferrite. The data of thermal analysis, infrared and X-ray diffraction, we show that the synthesis product in blanket form moving slowly in several stages, while that in
the synthesis furnace gets the product directly. We noted the tendency of the formation of smaller particles for the samples from the thermal blanket, as well as high surface areas for these samples, those prepared in a muffle grating.
Images by transmission electron microscopy confirm the observations made by x-ray diffraction measurements of surface areas by BET model. The magnetic measurements show ferromagnetic phenomenon only for the sample produced
in a muffle. The saturation magnetization was calculated by extrapolation, and their values are promising when compared with the literature. The Curie temperatures were estimated for some samples and all values were well above room temperature.
Descrição
Palavras-chave
Citação
ALVES, Thiago Eduardo Pereira. Synthesis, Characterization and Study of Magnetic Properties of Zn1-xFexO (0.00 ≤ x ≤ 0.09) produced by combustion reaction. 2010. 98 f. Dissertação (Mestrado em Educação em Química) - Universidade Federal de Goiás, Goiânia, 2010.