TITLE:
Synthesis and Characterization of Superparamagnetic Fe3O4@SiO2 Core-Shell Composite Nanoparticles
AUTHORS:
Meizhen Gao, Wen Li, Jingwei Dong, Zhirong Zhang, Bingjun Yang
KEYWORDS:
Magnetite Nanoparticles, Fe3O4@SiO2 Composite Nanoparticles, Dispersion, Thermal Stability, Particle Size, Magnetic Property
JOURNAL NAME:
World Journal of Condensed Matter Physics,
Vol.1 No.2,
May
6,
2011
ABSTRACT: The Fe3O4@SiO2 composite nanoparticles were obtained from as-synthesized magnetite (Fe3O4) nanoparticles through the modified Stöber method. Then, the Fe3O4 nanoparticles and Fe3O4@SiO2 composite nanoparticles were characterized by means of X-ray diffraction (XRD), Raman spectra, scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). Recently, the studies focus on how to improve the dispersion of composite particle and achieve good magnetic performance. Hence effects of the volume ratio of tetraethyl orthosilicate (TEOS) and magnetite colloid on the structural, morphological and magnetic properties of the composite nanoparticles were systematically investi-gated. The results revealed that the Fe3O4@SiO2 had better thermal stability and dispersion than the magnetite nanoparticles. Furthermore, the particle size and magnetic property of the Fe3O4@SiO2 composite nanoparticles can be adjusted by changing the volume ratio of TEOS and magnetite colloid.