Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell Nanoparticles
Understanding saturation magnetization and its behavior with particle size and temperature are essential for medical applications such magnetic hyperthermia. We report the effect of shell thickness and field cooling on the saturation magnetization and its behavior with temperature in Fe3O4/γ-Fe2O3 c...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2017-12-01
|
| Series: | Applied Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2076-3417/7/12/1269 |
| _version_ | 1819158209635549184 |
|---|---|
| author | Ihab M. Obaidat Chiranjib Nayek Kaustuv Manna |
| author_facet | Ihab M. Obaidat Chiranjib Nayek Kaustuv Manna |
| author_sort | Ihab M. Obaidat |
| collection | DOAJ |
| description | Understanding saturation magnetization and its behavior with particle size and temperature are essential for medical applications such magnetic hyperthermia. We report the effect of shell thickness and field cooling on the saturation magnetization and its behavior with temperature in Fe3O4/γ-Fe2O3 core/shell nanoparticles of fixed core diameter (8 nm) and several shell thicknesses. X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM, high-resolution transmission electron microscopy (HRTEM)) were used to investigate the phase and the morphology of the samples. Selected area electron diffraction (SAED) confirmed the core/shell structure and phases. Using a SQUID (San Diego, CA, USA), magnetic measurements were conducted in the temperature range of 2 to 300 K both under zero field-cooling (ZFC) and field-cooling (FC) protocols at several field-cooling values. In the ZFC state, considerable enhancement of saturation magnetization was obtained with the increase of shell thickness. After field cooling, we observed a drastic enhancement of the saturation magnetization in one sample up to 120 emu/g (50% larger than the bulk value). In both the FC and ZFC states, considerable deviations from the original Bloch’s law were observed. These results are discussed and attributed to the existence of interface spin-glass clusters which are modified by the changes in the shell thickness and the field-cooling. |
| first_indexed | 2024-12-22T16:21:01Z |
| format | Article |
| id | doaj.art-c2ce3b963eae4101b02897b7059652a4 |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-12-22T16:21:01Z |
| publishDate | 2017-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-c2ce3b963eae4101b02897b7059652a42022-12-21T18:20:15ZengMDPI AGApplied Sciences2076-34172017-12-01712126910.3390/app7121269app7121269Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell NanoparticlesIhab M. Obaidat0Chiranjib Nayek1Kaustuv Manna2Department of Physics, United Arab Emirates University, Al-Ain 15551, UAEDepartment of Physics, United Arab Emirates University, Al-Ain 15551, UAEMax-Planck-Institute for Chemical Physics of Solids, Nöthnitzer Straße-40, 01187 Dresden, GermanyUnderstanding saturation magnetization and its behavior with particle size and temperature are essential for medical applications such magnetic hyperthermia. We report the effect of shell thickness and field cooling on the saturation magnetization and its behavior with temperature in Fe3O4/γ-Fe2O3 core/shell nanoparticles of fixed core diameter (8 nm) and several shell thicknesses. X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM, high-resolution transmission electron microscopy (HRTEM)) were used to investigate the phase and the morphology of the samples. Selected area electron diffraction (SAED) confirmed the core/shell structure and phases. Using a SQUID (San Diego, CA, USA), magnetic measurements were conducted in the temperature range of 2 to 300 K both under zero field-cooling (ZFC) and field-cooling (FC) protocols at several field-cooling values. In the ZFC state, considerable enhancement of saturation magnetization was obtained with the increase of shell thickness. After field cooling, we observed a drastic enhancement of the saturation magnetization in one sample up to 120 emu/g (50% larger than the bulk value). In both the FC and ZFC states, considerable deviations from the original Bloch’s law were observed. These results are discussed and attributed to the existence of interface spin-glass clusters which are modified by the changes in the shell thickness and the field-cooling.https://www.mdpi.com/2076-3417/7/12/1269nanoparticlesmagnetizationshell thicknessBloch’s law |
| spellingShingle | Ihab M. Obaidat Chiranjib Nayek Kaustuv Manna Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell Nanoparticles Applied Sciences nanoparticles magnetization shell thickness Bloch’s law |
| title | Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell Nanoparticles |
| title_full | Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell Nanoparticles |
| title_fullStr | Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell Nanoparticles |
| title_full_unstemmed | Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell Nanoparticles |
| title_short | Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe3O4/γ-Fe2O3 Core/Shell Nanoparticles |
| title_sort | investigating the role of shell thickness and field cooling on saturation magnetization and its temperature dependence in fe3o4 γ fe2o3 core shell nanoparticles |
| topic | nanoparticles magnetization shell thickness Bloch’s law |
| url | https://www.mdpi.com/2076-3417/7/12/1269 |
| work_keys_str_mv | AT ihabmobaidat investigatingtheroleofshellthicknessandfieldcoolingonsaturationmagnetizationanditstemperaturedependenceinfe3o4gfe2o3coreshellnanoparticles AT chiranjibnayek investigatingtheroleofshellthicknessandfieldcoolingonsaturationmagnetizationanditstemperaturedependenceinfe3o4gfe2o3coreshellnanoparticles AT kaustuvmanna investigatingtheroleofshellthicknessandfieldcoolingonsaturationmagnetizationanditstemperaturedependenceinfe3o4gfe2o3coreshellnanoparticles |