Analysis of the magnetic properties of core-shell iron oxide nanoparticles



Título del documento: Analysis of the magnetic properties of core-shell iron oxide nanoparticles
Revista: Revista mexicana de física
Base de datos: PERIÓDICA
Número de sistema: 000460661
ISSN: 0035-001X
Autores: 1
1
3
1
2
1
Instituciones: 1Universidad de Guadalajara, Centro Universitario de la Ciénega, Ocotlán, Jalisco. México
2Universidad de Guadalajara, Centro Universitario de Ciencias Económico Administrativas, Zapopan, Jalisco. México
3Universidad de Guanajuato, División de Ciencias e Ingenierías, León, Guanajuato. México
Año:
Periodo: Jul-Ago
Volumen: 68
Número: 4
País: México
Idioma: Inglés
Tipo de documento: Artículo
Enfoque: Analítico, teórico
Resumen en inglés We report on the magnetization of core-shells nanoparticles. Magnetic nanoparticles (MNPs) with a core of magnetite of 13 nm diameter covered with a shell of dopamine (1.1 nm thickness) are studied through vibrating sample magnetometer (VSM), Monte Carlo (MC) computer simulations, and using an analytical model. All parameters involved in the theoretical analysis are experimentally determined, namely, the magnetic moment, temperature, magnetic field, core diameter, shell thickness, magnetic anisotropy, and particle concentration. The dependence of the magnetization with the magnetic field obtained through VSM and MC shows a 1% discrepancy in the magnetic saturation and up to 40% in the initial magnetic susceptibility. However, the dependence of the magnetization with the temperature obtained by MC indicates that the MNPs obey the Curie law above a critical temperature of 100 K. Furthermore, our findings indicate that the dipolar interactions play an important role on the magnetization in the interval 20 < T < 100 K. That critical temperature domain is very close to the blocking temperature measured following the zero-field-cooled and zero-cooled protocols, where the dipolar interactions between MNPs become significant. Further analysis shows a Langevin-like behavior for both experimental and theoretical magnetizations
Disciplinas: Física y astronomía,
Física
Palabras clave: Dopamina,
Nanopartículas,
Magnetización,
Núcleo
Keyword: Physics,
Dopamine,
Nanoparticles,
Magnetization,
Core-shell
Texto completo: Texto completo (Ver HTML) Texto completo (Ver PDF)