Title:
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Arc-discharge synthesis of iron encapsulated in carbon nanoparticles for biomedical applications
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Author:
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Chaitoglou, Stefanos; Sanaee, Mohammad Reza; Aguiló Aguayo, Noemí; Bertrán Serra, Enric
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Abstract:
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The objective of the present work is to improve the protection against the oxidation that usually appears in core@shell nanoparticles. Spherical iron nanoparticles coated with a carbon shell were obtained by a modified arc-discharge reactor, which permits controlling the diameter of the iron core and the carbon shell of the particles. Oxidized iron nanoparticles involve a loss of the magnetic characteristics and also changes in the chemical properties. Our nanoparticles show superparamagnetic behavior and high magnetic saturation owing to the high purity α-Fe of core and to the high core sealing, provided by the carbon shell. A liquid iron precursor was injected in the plasma spot dragged by an inert gas flow. A fixed arc-discharge current of 40 A was used to secure a stable discharge, and several samples were produced at different conditions. Transmission electron microscopy indicated an iron core diameter between 5 and 9 nm. Selected area electron diffraction provided evidences of a highly crystalline and dense iron core. The magnetic properties were studied up to 5 K temperature using a superconducting quantum interference device. The results reveal a superparamagnetic behaviour, a narrow size distribution (), and an average diameter of 6 nm for nanoparticles having a blocking temperature near 40 K. |
Subject(s):
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-Nanopartícules -Òxid de ferro -Propietats magnètiques -Nanoparticles -Ferric oxide -Magnetic properties |
Rights:
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cc-by (c) Chaitoglou, S. et al., 2014
http://creativecommons.org/licenses/by/3.0/es |
Document type:
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Article Article - Published version |
Published by:
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Hindawi Publishing Corporation
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