Mossbauer spectroscopy study of iron oxide nanoparticles obtained by spray pyrolysis

• Autor(a) principal: Marques, R. F. C. [UNESP]
• Data de Publicação: 2009
• Outros Autores: Rodriguez, A. F. R., Coaquira, J. A. H., Santos, J. G., Garg, V. K., Jafelicci, M. [UNESP], Ribeiro, S. J. L. [UNESP], Verelst, M., Dexpert-Ghys, J., Morais, P. C., Kuzmann, E., Lazar, K.
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1007/978-3-642-01369-0_20; http://hdl.handle.net/11449/197392
• topic: Magnetite; Hematite; Spray pyrolysis; Mossbauer spectroscopy

Mossbauer spectroscopy was used in this study to investigate magnetite nanoparticles, obtained by spray pyrolysis and thermal treatment under H-2 reduction atmosphere. Room temperature XRD data indicate the formation of magnetite phase and a second phase (metallic iron) which amount increases as the time of reduction under H-2 is increased. While room temperature Mossbauer data confirm the formation of the cubic phase of magnetite and the occurrence of metallic iron phase, the more complex features of 77 K-Mossbauer spectra suggest the occurrence of electronic localization favored by the different crystalline phase of magnetite at low temperatures which transition to the lower symmetry structure should occur at T similar to 120 K (Verwey transition).