Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8152738 | Journal of Magnetism and Magnetic Materials | 2018 | 23 Pages |
Abstract
This study reports on the synthesis and characterization of oleic acid (OA)-coated Fe3O4 nanoparticles (Fe3O4@OA) and AO plus essential oil (EO)-coated Fe3O4 nanoparticles (Fe3O4@OA/EO). The EO was extracted from Croton cajucara Benth (CCB) leaves; a plant from the Brazilian Amazon region. Structural and morphological characterizations were carried out using X-ray diffraction (XRD) and transmission electron microscopy (TEM) images, respectively. Additionally, thermogravimetric analysis and magnetization measurements (hysteresis cycle, zero field-cooled-ZFC, field-cooled-FC, and AC susceptibility) were used to assess thermal and magnetic properties of the as-fabricated samples. Rietveld refinement of XRD pattern confirmed the formation of magnetite phase with no extra phases, whereas TEM images revealed spherically-shaped nanoparticles in the Fe3O4@OA and (Fe3O4@OA/EO) samples with a mean physical size of 8.5â¯nm and 10.1â¯nm, respectively. ZFC and FC curves revealed the occurrence of blocked/frozen state below the maximum peak (Tmax) at â¼81â¯K and â¼40â¯K for the Fe3O4@OA and (Fe3O4@OA/EO) samples, respectively. Moreover, low-temperature AC susceptibility vs. T curves recorded in the range of 0.2-1000â¯Hz showed that the OA coating of the Fe3O4 nanoparticles leads to a spin-glass-like behavior credited to the strong particle-particle interactions; meanwhile, the double layer (AOâ¯+â¯EO) coating of the Fe3O4 nanoparticles remarkably quenches the particle-particle interaction leading to a superparamagnetic-like behavior.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
J.J.A. Medrano, F.F.H. Aragón, L. Leon-Felix, J.A.H. Coaquira, A.F.R. RodrÃguez, F.S.E.D.V. Faria, M.H. Sousa, J.C. Mantilla Ochoa, P.C. Morais,