Controlled formation of reactive Fe particles dispersed in a carbon matrix active for the oxidation of aqueous contaminants with H2O2

• Autor(a) principal: Tristão, Juliana Cristina
• Data de Publicação: 2014
• Outros Autores: Mendonça, Fernanda Gomes de, Lago, Rochel Montero, Ardisson, José Domingos
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://link.springer.com/article/10.1007%2Fs11356-014-2554-z; http://www.locus.ufv.br/handle/123456789/19161
• topic: Magnetic nanoparticles; Iron oxides; Iron nanoparticles; Carbon matrix; Sucrose; Heterogeneous; Fenton

In this work, reactive iron nanoparticles dispersed in a carbon matrix were produced by the controlled thermal decomposition of Fe3+ ions in sucrose. During the sucrose decomposition, the Fe3+ ions are reduced to form iron nanometric cores dispersed in a porous carbonaceous matrix. The materials were prepared with iron contents of 1, 4, and 8 wt.% and heated at 400, 600, and 800 °C. Analyses by X-ray diffraction, Mössbauer spectroscopy, magnetization measurements, Raman spectroscopy, termogravimetric analyses, BET surface area, scanning, and transmission electron microscopy showed that at 400 °C, the materials are composed essentially of Fe3O4 particles, while treatments at higher temperatures, i.e., 600 and 800 °C, produced phases such as Fe0 and Fe3C. The composites were tested for the oxidation of methylene blue with H2O2 by a Fenton-type reaction and also H2O2 decomposition, showing better performance for the material containing 8 % of iron heated at 400 and 600 °C. These results are discussed in terms of Fe2+ surface species in the Fe3O4 nanoparticles active for the Fenton reaction.