高等学校化学学报 ›› 2000, Vol. 21 ›› Issue (S1): 233.

• Chemistry in Materials Sciences • 上一篇    下一篇

Synthesis, Characterization and Self-assembly of Gold-coated Iron Nanoparticles

LIN Jun1, ZHOU Wei-Lie2, CARPENTER E.-E.2, O'CONNOR Charles-J.2   

  1. 1. Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 159 Renmin Street, Changchun 130022;
    2. Advanced Materials Reseach Institute, College of Science, University of New Orleans, New Orleans, LA 70148, USA
  • 出版日期:2000-12-31 发布日期:2000-12-31

Synthesis, Characterization and Self-assembly of Gold-coated Iron Nanoparticles

LIN Jun1, ZHOU Wei-Lie2, CARPENTER E.-E.2, O'CONNOR Charles-J.2   

  1. 1. Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 159 Renmin Street, Changchun 130022;
    2. Advanced Materials Reseach Institute, College of Science, University of New Orleans, New Orleans, LA 70148, USA
  • Online:2000-12-31 Published:2000-12-31

摘要:

Due to their small size (1-100 nm), nanoparticles exhibit novel materials properties that differ considerably from those of the bulk solid state. Especially in recent years, the interests in nanometer-scale magnetic particles are growing based on their potential application as high density magnetic storage media. A unique reverse micelle method has been developed to prepare gold-coated iron nanoparticles. XRD, UV/vis, TEM and magnetic measurements are used to characterize the nanocomposites. XRD only gives FCC paterns of gold for the obtained nanoparticles. There is a red shift and broadening of Au@Fe colloid relative to pure gold colloid in the absorption spectra. TEM results show that the average size of Au@Fe nanoparticle is about 10 nm. These nanoparticles self-assembled into wires in micron level under a 0.5 T magnetic field. Magnetic measurements show that the particles are superparamagnetic with a blocking temperature of 42 K. Coercivity of the obtained nanoparticles decreases with the measuring temperature, which are 730 Oe,320 Oe and 0 at 2 K, 10 K and 300 K, respectively.

Abstract:

Due to their small size (1-100 nm), nanoparticles exhibit novel materials properties that differ considerably from those of the bulk solid state. Especially in recent years, the interests in nanometer-scale magnetic particles are growing based on their potential application as high density magnetic storage media. A unique reverse micelle method has been developed to prepare gold-coated iron nanoparticles. XRD, UV/vis, TEM and magnetic measurements are used to characterize the nanocomposites. XRD only gives FCC paterns of gold for the obtained nanoparticles. There is a red shift and broadening of Au@Fe colloid relative to pure gold colloid in the absorption spectra. TEM results show that the average size of Au@Fe nanoparticle is about 10 nm. These nanoparticles self-assembled into wires in micron level under a 0.5 T magnetic field. Magnetic measurements show that the particles are superparamagnetic with a blocking temperature of 42 K. Coercivity of the obtained nanoparticles decreases with the measuring temperature, which are 730 Oe,320 Oe and 0 at 2 K, 10 K and 300 K, respectively.

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