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Thermosensitivity Through Exchange Coupling in Ferrimagnetic/Antiferromagnetic Nano-Objects for Magnetic Based Thermometry



Frank Abel, Eduardo De Lima Correa, Adam Biacchi, Thinh Bui, Solomon I. Woods, Angela R. Hight Walker, Cindi L. Dennis


Temperature is a fundamental physical quantity important to the physical and biological sciences. Measurement of temperature within an optically inaccessible three-dimensional (3D) volume at microscale resolution is currently limited. Thermal magnetic particle imaging (T-MPI), a temperature variant of magnetic particle imaging (MPI), hopes to solve this deficiency. For this thermometry technique, magnetic nano-objects (MNOs) with strong temperature-dependent magnetization (thermosensitivity) around the temperature of interest are required; here we focus between 200 K and 310 K. We demonstrate that thermosensitivity can be amplified in MNOs consisting of ferrimagnetic (FiM) iron oxide (ferrite) and antiferromagnetic (AFM) cobalt oxide (CoO) through interface effects. The FiM/AFM MNOs are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Raman spectroscopy. The thermosensitivity is evaluated and quantified by temperature-dependent magnetic measurements. The FiM/AFM exchange coupling is confirmed by field-cooled (FC) hysteresis loops measured at 100 K. Magnetic particle spectroscopy (MPS) measurements were performed at room temperature to evaluate the MNOs MPI response. This initial study shows that FiM/AFM interfacial magnetic coupling is a viable method to increase thermosensitivity in MNOs for T-MPI.
ACS Applied Materials and Interfaces


magnetic nano-objects, FiM/AFM exchange coupling, colloidal synthesis, thermal magnetic particle imaging, thermosensitivity


Abel, F. , De Lima Correa, E. , Biacchi, A. , Bui, T. , Woods, S. , Hight Walker, A. and Dennis, C. (2023), Thermosensitivity Through Exchange Coupling in Ferrimagnetic/Antiferromagnetic Nano-Objects for Magnetic Based Thermometry, ACS Applied Materials and Interfaces, [online],, (Accessed May 29, 2024)


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Created March 6, 2023, Updated May 9, 2023