Magnetic nanoparticles for power absorption: Optimizing size, shape and magnetic properties

Journal Article · Thu Oct 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.07.047· OSTI ID:21372345

Gonzalez-Fernandez, M A ^[1]; Torres, T E ^[2]; Andres-Verges, M ^[3]; Costo, R ^[1]; Presa, P de la ^[4]; Serna, C J; Morales, M P ^[1]; Marquina, C ^[5]; Ibarra, M R ^[2]

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1. Instituto de Ciencia de Materiales de Madrid, CSIC, Madrid (Spain)
2. Instituto de Nanociencia de Aragon, Universidad de Zaragoza, Zaragoza (Spain)
3. Departamento de Quimica Organica e Inorganica, Universidad de Extremadura, Badajoz (Spain)
4. Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC, Las Rozas, Madrid (Spain)
5. Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza (Spain)

We present a study on the magnetic properties of naked and silica-coated Fe{sub 3}O{sub 4} nanoparticles with sizes between 5 and 110 nm. Their efficiency as heating agents was assessed through specific power absorption (SPA) measurements as a function of particle size and shape. The results show a strong dependence of the SPA with the particle size, with a maximum around 30 nm, as expected for a Neel relaxation mechanism in single-domain particles. The SiO{sub 2} shell thickness was found to play an important role in the SPA mechanism by hindering the heat outflow, thus decreasing the heating efficiency. It is concluded that a compromise between good heating efficiency and surface functionality for biomedical purposes can be attained by making the SiO{sub 2} functional coating as thin as possible. - Graphical Abstract: The magnetic properties of Fe{sub 3}O{sub 4} nanoparticles from 5 to 110 nm are presented, and their efficiency as heating agents discussed as a function of particle size, shape and surface functionalization.

• OSTI ID: 21372345
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 10; Other Information: DOI: 10.1016/j.jssc.2009.07.047; PII: S0022-4596(09)00359-4; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ABSORPTION
HEATING
IRON OXIDES
MAGNETIC PROPERTIES
NANOSTRUCTURES
PARTICLE SIZE
SILICA
SILICON OXIDES
CHALCOGENIDES
IRON COMPOUNDS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SILICON COMPOUNDS
SIZE
SORPTION
TRANSITION ELEMENT COMPOUNDS