View in EDS

Tailoring the structural and magnetic properties of Co-Zn nanosized ferrites for hyperthermia applications.

Saved in:
Bibliographic Details
Title: Tailoring the structural and magnetic properties of Co-Zn nanosized ferrites for hyperthermia applications.
Authors: Gómez-Polo, C.1 gpolo@unavarra.es, Recarte, V.1, Cervera, L.1, Beato-López, J.J.1, López-García, J.1, Rodríguez-Velamazán, J.A.1, Ugarte, M.D.1, Mendonça, E.C.1, Duque, J.G.S.1
Source: Journal of Magnetism & Magnetic Materials. Nov2018, Vol. 465, p211-219. 9p.
Subjects: Magnetic properties of metals, Zinc, Ferrites, Magnetic nanoparticle hyperthermia, Magnetic anisotropy, Coprecipitation (Chemistry)
Abstract: Highlights • Structural, magnetic and hyperthermia studies of Co x Zn 1− x Fe 2 O 4 nanoparticles. • Maximum magnetization values for x = 0.5 associated to cation distribution. • Decrease in Curie point and magnetocrystalline anisotropy with Zn content. • Occurrence of canted spin arrangement (Y-K angle). • Optimum self-controlled temperature hyperthermia agents. Abstract A comparative study of the magnetic properties (magnetic moment, magnetocrystalline anisotropy) and hyperthermia response in Co-Zn spinel nanoparticles is presented. The Co x Zn 1− x Fe 2 O 4 nanoparticles (x = 1, 0.5, 0.4, 0.3, 0.2 and 0.1) were synthesized by co-precipitated method and the morphology and mean crystallite size (around 10 nm) of the nanoparticles were analysed by TEM Microscopy. Regarding the magnetic characterization (SQUID magnetometry), Co-Zn nanoparticles display at room temperature anhysteretic magnetization curves, characteristic of the superparamagnetic behavior. A decrease in the blocking temperature, T B , with Zn content is experimentally detected that can be ascribed to the reduction in the mean nanoparticle size as x decreases. Furthermore, the reduction in the magnetocrystalline anisotropy with Zn inclusion is confirmed through the analysis of T B versus the mean volume of the nanoparticles and the law of approach to saturation. Maximum magnetization is achieved for x = 0.5 as a result of the cation distribution between octahedral and tetrahedral spinel sites, analysed by neutron diffraction studies. The occurrence of a canted spin arrangement (Yafet-Kittel angle) is introduced to properly fit the magnetic spinel structures. Finally, the heating capacity of these spinel ferrites is analyzed under ac magnetic field (magnetic hyperthermia). Maximum SAR (Specific Absorption Rate) values are achieved for x = 0.5 that should be correlated to the maximum magnetic moment of this composition. [ABSTRACT FROM AUTHOR]
Copyright of Journal of Magnetism & Magnetic Materials is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:Highlights • Structural, magnetic and hyperthermia studies of Co x Zn 1− x Fe 2 O 4 nanoparticles. • Maximum magnetization values for x = 0.5 associated to cation distribution. • Decrease in Curie point and magnetocrystalline anisotropy with Zn content. • Occurrence of canted spin arrangement (Y-K angle). • Optimum self-controlled temperature hyperthermia agents. Abstract A comparative study of the magnetic properties (magnetic moment, magnetocrystalline anisotropy) and hyperthermia response in Co-Zn spinel nanoparticles is presented. The Co x Zn 1− x Fe 2 O 4 nanoparticles (x = 1, 0.5, 0.4, 0.3, 0.2 and 0.1) were synthesized by co-precipitated method and the morphology and mean crystallite size (around 10 nm) of the nanoparticles were analysed by TEM Microscopy. Regarding the magnetic characterization (SQUID magnetometry), Co-Zn nanoparticles display at room temperature anhysteretic magnetization curves, characteristic of the superparamagnetic behavior. A decrease in the blocking temperature, T B , with Zn content is experimentally detected that can be ascribed to the reduction in the mean nanoparticle size as x decreases. Furthermore, the reduction in the magnetocrystalline anisotropy with Zn inclusion is confirmed through the analysis of T B versus the mean volume of the nanoparticles and the law of approach to saturation. Maximum magnetization is achieved for x = 0.5 as a result of the cation distribution between octahedral and tetrahedral spinel sites, analysed by neutron diffraction studies. The occurrence of a canted spin arrangement (Yafet-Kittel angle) is introduced to properly fit the magnetic spinel structures. Finally, the heating capacity of these spinel ferrites is analyzed under ac magnetic field (magnetic hyperthermia). Maximum SAR (Specific Absorption Rate) values are achieved for x = 0.5 that should be correlated to the maximum magnetic moment of this composition. [ABSTRACT FROM AUTHOR]
ISSN:03048853
DOI:10.1016/j.jmmm.2018.05.051