Resumo de eventos cient??ficos
Annealing effect on the structural and local magnetic properties of nickel ferrite nanoparticles studied by hyperfine interaction measurements
Registro en:
0000-0002-4499-5949
0000-0003-3023-1718
Autor
RODRIGUES, PRISCILA S.
MATOS, IZABELA T.
SALES, TATIANE S.
BURIMOVA, ANASTASIA
CABRERA-PASCA, GABRIEL
PEREIRA, LUCIANO F.
SAXENA, RAJENDRA N.
OTUBO, LARISSA
CARBONARI, ARTUR W.
ANNUAL CONFERENCE ON MAGNETISM AND MAGNETIC MATERIALS, 65th
Resumen
Nickel ferrite in the form of nanoparticles is a technologically important material that can be
applied for the production of biosensors, catalysts, drug delivery, and magnetic resonance contrast agents. In
this work NiFe O samples comprising spherical nanoparticles of ~6 nm in diameter have been synthesized via
a thermal decomposition route. The quality control of the samples was carried out with conventional
techniques including X-ray diffraction and transmission electron microscopy. Post-synthesis XRD pattern
revealed textured spinel NiFe O . Local magnetic properties were examined with Time Differential Perturbed
Angular Correlation (TDPAC) spectroscopy within the 12 - 773K temperature range with In( Cd) probe
introduced into the samples at synthesis. Quasi-static magnetic properties were observed (including above
room temperature), as expected due to the small time window of TDPAC. The TDPAC results shown in Fig. 1
were analyzed using a model with combined electric quadrupole and magnetic dipole interactions. An
expressive dynamic interaction was observed upon heating after synthesis. A theoretical model based on the
Brillouin function for different ionic moments was applied to study the evolution of the hyperfine magnetic field
with temperature (see Fig. 1-2) and allowed to attribute the magnetic interaction to the probe location at Fe3+ site. Site occupancy and the interplay between magnetic and structural properties are discussed with respect
to application perspectives.