Synthesis and characterization of Fe3O4@Ag core-shell: structural, morphological, and magnetic properties

Document Type: Research Paper

Authors

Department of Basic Sciences, Tarbiat Modares University (TMU), P.O. Box 14115-175, Tehran, Iran

Abstract

This paper is a report on the synthesis of the Fe3O4@Ag core-shell with high saturation magnetization of magnetite nanoparticles as the core, by using polyol route and silver shell by chemical reduction. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy analyses confirmed that the particles so produced were monophase. The magnetic properties of the product were investigated by using a vibrating sample magnetometer. Magnetic saturation of magnetite was 91 emu/g that around about bulk magnetization. This high saturation magnetization can be attributed to the thin dead layer. By using polyethylene glycol as a surfactant to separate and restrict the growth of the particles, magnetostatic interactions are in good agreement with the remanence ratio analysis. Morphology and the average size of the particles were determined with field emission scanning electron microscope (FESEM). Spherical aggregates of Fe3O4 (size around 73 nm) are composed of a small primary particle size of about 16 nm. Silver deposition was done using butylamine as the reductant of AgNO3 in ethanol with different ratio. The silver layers were estimated using statistical histogram images of FESEM. Silver-coated iron oxide nanohybrids have been used in a broad range of applications, including chemical and biological sensing, due to the broad absorption in the optical region associated with localized surface plasmon resonance.

Keywords


[1].1. Mikhaylova, M., et al., Superparamagnetism of magnetite nanoparticles: dependence on surface modification. Langmuir, 2004. 20(6): p. 2472-2477.
[2].2. Suto, M., et al., Heat dissipation mechanism of magnetite nanoparticles in magnetic fluid hyperthermia. Journal of Magnetism and Magnetic Materials, 2009. 321(10): p. 1493-1496.
[3].3. Wan, J., et al., Monodisperse water-soluble magnetite nanoparticles prepared by polyol process for high-performance magnetic resonance imaging. Chemical Communications, 2007(47): p. 5004-5006.
[4].4. Jain, P.K., et al., Surface plasmon resonance enhanced magneto-optics (SuPREMO):
Faraday rotation enhancement in gold-coated iron oxide nanocrystals. Nano letters, 2009. 9(4): p. 1644-1650.
[5].5. Ji, X., et al., Bifunctional gold nanoshells with a superparamagnetic iron oxide-silica core suitable for both MR imaging and photothermal therapy. The Journal of Physical Chemistry C, 2007. 111(17): p. 6245-6251.
[6].6. Bohren, C.F. and D.R. Huffman, Absorption and scattering of light by small particles. 2008: Wiley-Vch.
[7].7. Saha, K., et al., Gold nanoparticles in chemical and biological sensing. Chemical reviews, 2012. 112(5): p. 2739-2779.
[8].8. Huang, X., et al., Plasmonic photothermal therapy (PPTT) using gold nanoparticles. Lasers in medical science, 2008. 23(3): p. 217-228.
[9].9. Valenzuela, R., et al., Influence of stirring velocity on the synthesis of magnetite nanoparticles (Fe3O4) by the co-precipitation method. Journal of Alloys and Compounds, 2009. 488(1): p. 227-231.
[10]. 10. Hee Kim, E., et al., Synthesis of ferrofluid with magnetic nanoparticles by sonochemical method for MRI contrast agent. Journal of Magnetism and Magnetic Materials, 2005. 289(0): p. 328-330.
[11]. 11. Cai, W. and J. Wan, Facile synthesis of superparamagnetic magnetite nanoparticles in liquid polyols. Journal of Colloid and Interface Science, 2007. 305(2): p. 366-370.
[12]. 12. Cao, S.-W., Y.-J. Zhu, and J. Chang, Fe3O4 polyhedral nanoparticles with a high magnetization synthesized in mixed solvent ethylene glycol–water system. New Journal of Chemistry, 2008. 32(9): p. 1526-1530.
[13]. 13. Drake, N.L. and T.B. Smith, THE DECOMPOSITION OF ETHYLENE GLYCOL IN THE PRESENCE OF CATALYSTS. I. VANADIUM PENTOXIDE AS CATALYST. Journal of the American Chemical Society, 1930. 52(11): p. 4558-4566.
[14]. 14. Ding, T., et al., Sonochemical synthesis and characterizations of monodispersed PbSe nanocrystals in polymer solvent. journal of crystal growth, 2002. 235(1): p. 517-522.
[15]. 15. Dobryszycki, J. and S. Biallozor, On some organic inhibitors of zinc corrosion in alkaline media. Corrosion science, 2001. 43(7): p. 1309-1319.

[16]. 16. Bognitzki, M., et al., Polymer, metal, and hybrid nano‐and mesotubes by coating degradable polymer template fibers (TUFT process). Advanced Materials, 2000. 12(9): p. 637-640.
[17]. 17. Deng, H., et al., Monodisperse Magnetic Single‐Crystal Ferrite Microspheres.
Angewandte Chemie, 2005. 117(18): p. 2842-2845.
[18]. 18. Kim, K., et al., Silanization of Ag-Deposited Magnetite Particles: An Efficient Route to Fabricate Magnetic Nanoparticle-Based Raman Barcode Materials. ACS Applied Materials & Interfaces, 2010. 2(7): p. 1872-1878.