TY - JOUR
T1 - Growth mechanisms and oxidation resistance of gold-coated iron nanoparticles
AU - Cho, Sung Jin
AU - Idrobo, Juan Carlos
AU - Olamit, Justin
AU - Liu, Kai
AU - Browning, Nigel D.
AU - Kauzlarich, Susan M.
PY - 2005/6/14
Y1 - 2005/6/14
N2 - We report the chemical synthesis of Fe-core/Au-shell nanoparticles by a reverse micelle method and the investigation of their growth mechanisms and oxidation-resistant characteristics. The core-shell structure and the presence of the Fe and Au phases have been confirmed by transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Mössbauer spectroscopy, and inductively coupled plasma techniques. Additionally, atomic-resolution Z-contrast imaging and electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM) have been used to study details of the growth processes. The Au shell grows by nucleating on the Fe-core surface before coalescing. The magnetic moments of such nanoparticles, in the loose powder form, decrease over time due to oxidation. The less than ideal oxidation resistance of the Au shell may have been caused by the rough Au surfaces. However, in pressed pellet form, electrical transport measurements show that the particles are fairly stable, as the resistance of the pellet does not change appreciably over time.
AB - We report the chemical synthesis of Fe-core/Au-shell nanoparticles by a reverse micelle method and the investigation of their growth mechanisms and oxidation-resistant characteristics. The core-shell structure and the presence of the Fe and Au phases have been confirmed by transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Mössbauer spectroscopy, and inductively coupled plasma techniques. Additionally, atomic-resolution Z-contrast imaging and electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM) have been used to study details of the growth processes. The Au shell grows by nucleating on the Fe-core surface before coalescing. The magnetic moments of such nanoparticles, in the loose powder form, decrease over time due to oxidation. The less than ideal oxidation resistance of the Au shell may have been caused by the rough Au surfaces. However, in pressed pellet form, electrical transport measurements show that the particles are fairly stable, as the resistance of the pellet does not change appreciably over time.
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U2 - 10.1021/cm0500713
DO - 10.1021/cm0500713
M3 - Article
AN - SCOPUS:20744447350
VL - 17
SP - 3181
EP - 3186
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 12
ER -