Investigation of the Molecular Surface Coating on the Stability of Insulating Magnetic Oils
| Autor: | Maria A. G. Soler, Bartlomiej Andrzejewski, Gustavo B. Alcantara, Paulo C. Morais, Ewa Mosiniewicz-Szablewska, P.P.C. Sartoratto, Wesley Renato Viali |
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| Rok vydání: | 2009 |
| Předmět: |
Materials science
Iron oxide Mineralogy Maghemite engineering.material Surfaces Coatings and Films Electronic Optical and Magnetic Materials Colloid Surface coating chemistry.chemical_compound General Energy chemistry Chemical engineering engineering Surface modification Particle size Physical and Theoretical Chemistry Stoichiometry Magnetite |
| Zdroj: | The Journal of Physical Chemistry C. 114:179-188 |
| ISSN: | 1932-7455 1932-7447 |
| Popis: | Surface functionalization of a series of nanosized iron oxide particles (average diameter around 6 nm) with oleic acid was realized in this study. The aim is to suspend the surface-functionalized nanoparticulated materials in insulating mineral oil and evaluate their colloidal stability as a function of time. Nanoparticulated samples presenting stoichiometry close to maghemite were obtained by oxidation of a freshly precipitated magnetite sample. Systematic variations observed in the Fe3+/Fe2+ ratio, average particle size, and lattice constant were attributed to differences in oxidation route and oxidation condition employed. Morphological, compositional, thermal, optical and magnetic characterization techniques were used in the investigation of native (P, PN1, PN2, POX1, POX3, and POX7) and surface-functionalized (POA, PN1OA, PN2OA, POX1OA, POX3OA, and POX7OA) samples. While suspending the oleic-acid-coated nanosized iron oxide particles in insulating mineral oil, the best colloidal stability was achieve... |
| Databáze: | OpenAIRE |
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