Synthesis, structure and magnetic properties of SiO2-coated fe nanocapsules

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 454-455; pp. 211 - 215
• Main Authors: ZHANG, X. F, DONG, X. L, HUANG, H, LV, B, ZHU, X. G, LEI, J. P, MA, S, LIU, W, ZHANG, Z. D
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 25.04.2007
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Magnetic properties and materials; Magnetic properties of nanostructures; Materials science; Nanoscale materials and structures: fabrication and characterization; Other topics in nanoscale materials and structures; Physics; Catalysts; Core shell structure; Nanocapsules; Ferromagnetic materials; VLS growth; Iron; Amorphous state; VLS mechanism; Thickness; Nanoparticles; Synthesis; Nanocomposites; BCC lattices; Silicon oxides; Transition elements; Physical vapor deposition; Coated particle; Microstructure; Electric arcs; Magnetic properties
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2006.11.010

SiO2-coated Fe nanocapsules were synthesized by arc-discharge method using micron-sized powders as the raw materials. It was shown that most of nanocapsules were spherical with a 'core/shell'type structure. The shell was an amorphous SiO2 with around 10-20 nm in thickness and the core was a ferromagnetic Fe. The unique morphologies of the nanocapsules implied that the growth was governed by an extended mechanism of the vapor-liquid-solid (VLS) with the existence of stoichiometric oxygen. The Fe core was in a BCC structure and may play as a catalyst. This kind of 'core/shell'type nano-composite can involve multi-loss mechanisms for electromagnetic wave absorption and open a way to synthesizing serials of new 'core/shell' (metallic/dielectric) type nano-composites.