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Thermosensitivity through Exchange Coupling in Ferrimagnetic/Antiferromagnetic Nano-Objects for Magnetic-Based
Frank M Abel1, Eduardo L Correa1, Adam J Biacchi1
1National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States.
ACS Applied Materials & Interfaces
|March 6, 2023
Summary
New magnetic nano-objects enhance temperature measurement in optically inaccessible 3D volumes. This breakthrough in thermal magnetic particle imaging (T-MPI) uses ferrimagnetic/antiferromagnetic interfaces to boost thermosensitivity.
Area of Science:
- Materials Science
- Nanotechnology
- Biophysics
Background:
- Accurate temperature measurement at the microscale in 3D volumes is crucial for physical and biological sciences but remains challenging.
- Existing thermometry methods struggle with optically inaccessible environments and microscale resolution.
- Thermal magnetic particle imaging (T-MPI) offers a potential solution, but requires highly thermosensitive magnetic nano-objects (MNOs).
Purpose of the Study:
- To develop novel MNOs with enhanced temperature-dependent magnetization (thermosensitivity) for T-MPI applications.
- To investigate the role of interfacial effects in ferrimagnetic/antiferromagnetic (FiM/AFM) MNOs for amplified thermosensitivity.
- To evaluate MNOs for T-MPI in the temperature range of 200 K to 310 K.
Main Methods:
- Fabrication of MNOs combining ferrimagnetic (iron oxide) and antiferromagnetic (cobalt oxide) materials.
- Characterization using X-ray diffraction (XRD), (scanning) transmission electron microscopy (STEM/TEM), dynamic light scattering (DLS), and Raman spectroscopy.
- Evaluation of thermosensitivity via temperature-dependent magnetic measurements, field-cooled hysteresis loops, and magnetic particle spectroscopy (MPS).
Main Results:
- Demonstrated amplified thermosensitivity in FiM/AFM MNOs due to interface effects.
- Confirmed FiM/AFM exchange coupling through magnetic measurements.
- Verified the MNOs' response for T-MPI applications.
Conclusions:
- Interfacial magnetic coupling in FiM/AFM MNOs is a promising strategy to significantly increase thermosensitivity.
- These enhanced MNOs are viable for advancing T-MPI technology for microscale thermometry in challenging environments.
- The study provides a foundation for designing next-generation thermosensitive nanomaterials for advanced imaging techniques.
Keywords:
FiM/AFM exchange couplingcolloidal synthesismagnetic nano-objectsthermal magnetic particle imagingthermosensitivityMore Related Videos
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