Article

ChemInform Abstract: Synthesis of Highly Crystalline and Monodisperse Maghemite Nanocrystallites Without a Size-Selection Process.

School of Chemical Engineering and Institute of Chemical Processes, Seoul National University, Seoul 151-744, Korea.
Journal of the American Chemical Society (Impact Factor: 12.11). 04/2010; 123(51):12798-801. DOI: 10.1002/chin.200217234
Source: PubMed

ABSTRACT

The synthesis of highly crystalline and monodisperse gamma-Fe(2)O(3) nanocrystallites is reported. High-temperature (300 degrees C) aging of iron-oleic acid metal complex, which was prepared by the thermal decomposition of iron pentacarbonyl in the presence of oleic acid at 100 degrees C, was found to generate monodisperse iron nanoparticles. The resulting iron nanoparticles were transformed to monodisperse gamma-Fe(2)O(3) nanocrystallites by controlled oxidation by using trimethylamine oxide as a mild oxidant. Particle size can be varied from 4 to 16 nm by controlling the experimental parameters. Transmission electron microscopic images of the particles showed 2-dimensional and 3-dimensional assembly of particles, demonstrating the uniformity of these nanoparticles. Electron diffraction, X-ray diffraction, and high-resolution transmission electron microscopic (TEM) images of the nanoparticles showed the highly crystalline nature of the gamma-Fe(2)O(3) structures. Monodisperse gamma-Fe(2)O(3) nanocrystallites with a particle size of 13 nm also can be generated from the direct oxidation of iron pentacarbonyl in the presence of oleic acid with trimethylamine oxide as an oxidant.

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Available from: Jongnam Park, Aug 24, 2015
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    • "Iron oxide nanoparticles including magnetite (Fe 3 O 4 ), hematite (í µí»¼-Fe 2 O 3 ), maghemite (í µí»¾-Fe 2 O 3 ), goethite (í µí»¼-FeOOH), and akaganeite (í µí»½-FeOOH) nanoparticles have attracted enormous attention due to their interesting properties678910. Many methods have been developed for the preparation of í µí»¾-Fe 2 O 3 magnetic nanoparticles, including coprecipitation[11], a gas-phase reaction technique[12], direct thermal decomposition[13], thermal decomposition-oxidation[14], sonochemical synthesis[15], a microemulsion technique[16], hydrothermal synthesis[17], a vaporization-condensation method[18], and a sol-gel approach[19]. Reactions for the synthesis of oxide nanoparticles using the coprecipitation method can be grouped into two categories . "
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    • "The decomposition of iron pentacarbonyl in the presence of oleic acid is a well known method for Fe-NP formation[23]. Ferrocene has also been shown to decompose and form a carbon shell around the iron nanoparticles and has shown to exhibit novel structures[41]. "
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