title: Controlled formation of reactive Fe particles dispersed in a carbon matrix active for the oxidation of aqueous contaminants with H₂O₂.
abstract: In this work, reactive iron nanoparticles dispersed in a carbon matrix were produced by the controlled thermal decomposition of Fe(3+) ions in sucrose. During the sucrose decomposition, the Fe(3+) 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 Fe(0) 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 Fe(2+) surface species in the Fe3O4 nanoparticles active for the Fenton reaction.
authors: Universidade Federal de Viçosa, Campus de Florestal, Rodovia LMG 818, Km 6, Florestal, Minas Gerais, 35690-000, Brazil, juliana@ufv.br.
authors: Juliana Cristina
authors: JC
authors: Tristão
authors: Fernanda Gomes
authors: FG
authors: de Mendonça
authors: Rochel Montero
authors: RM
authors: Lago
authors: José Domingos
authors: JD
authors: Ardisson
mesh_terms: D002244:Carbon / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry* / Q000378:metabolism; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D013395:Sucrose; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000378:metabolism; D018508:Water Purification / Q000379:methods
chemical_list: D058185:Magnetite Nanoparticles; D014874:Water Pollutants, Chemical; D013395:Sucrose; D002244:Carbon; D006861:Hydrogen Peroxide