Uniform hollow magnetite spheres: Facile synthesis, growth mechanism, and their magnetic properties

Journal Article · Sat Nov 15 00:00:00 EST 2014 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2014.07.025· OSTI ID:22420635

Zhou, Xing ^[1]; Zhao, Guizhe ^[2]; Liu, Yaqing ^[2]

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1. School of Chemistry, Biology and Material Engineering, Suzhou University of Science and Technology, Suzhou 215009 (China)
2. Research Center for Engineering Technology of Polymeric Composites of Shanxi Province, North University of China, Taiyuan 030051 (China)

Highlights: • Uniform Fe{sub 3}O{sub 4} hollow spheres with high saturation magnetization were synthesized through a simple solvothermal process. • Without using any hard templates or external magnetic field. • The as-prepared magnetite hollow spheres exhibit a ferromagnetic behavior with high Ms of ca. 85.9 emu/g at room temperature. • The morphology of Fe{sub 3}O{sub 4} with nanoparticles, hollow, and irregular structures could be adjusted by changing the reactive conditions. - Abstract: Hierarchical porous Fe{sub 3}O{sub 4} hollow spheres with high saturation magnetization were synthesized through a simple solvothermal process in ethylene glycol (EG) in the presence of Tetrabutylammonium chloride (TBAC) and urea. By investigating the effect of reaction temperature, time, the amount of urea, and concentration of iron ion on the formation of hollow spheres, it was proposed that the main formation mechanism of hollow spheres is Ostwald ripening process combined with assembly-then-inside-out evacuation process. Additionally, it is found that the morphology of Fe{sub 3}O{sub 4} with nanoparticles, hollow, and irregular structures could be adjusted by changing the above factors. The resulting products were characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), high resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometer (VSM). The hierarchical porous Fe{sub 3}O{sub 4} hollow spheres exhibited enhanced saturation magnetization as compared with Fe{sub 3}O{sub 4} nanoparticles.

• OSTI ID: 22420635
• Journal Information: Materials Research Bulletin, Vol. 59; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CONCENTRATION RATIO
FERRITES
GLYCOLS
IRON IONS
IRON OXIDES
MAGNETIC FIELDS
MAGNETIC PROPERTIES
MAGNETITE
MAGNETIZATION
MICROSTRUCTURE
NANOPARTICLES
POROUS MATERIALS
SCANNING ELECTRON MICROSCOPY
TEMPERATURE RANGE 0273-0400 K
TRANSMISSION ELECTRON MICROSCOPY
VIBRATING SAMPLE MAGNETOMETERS
X-RAY DIFFRACTION
X-RAY SPECTROSCOPY