Characterization of Ferromagnetic Bimetallic Nanomaterials Using Electron Microscopy

  • Nabraj BhattaraiEmail author


Bimetallic ferromagnetic nanoparticles can be characterized using various techniques such as neutron scattering, magnetometry, electron microscopy, etc. The results from most of those techniques are from the average sample, not from individual nanoparticle. The property of nanoparticle is affected by its shape, size, chemical order, and composition. The atomic level characterization of each nanoparticle is essential and can be done by employing scanning/transmission electron microscopy (S/TEM). The use of Z-contrast imaging in STEM analysis of material permits distinguishing the atomic columns of the constituents, and the spectroscopic techniques (electron energy loss and energy-dispersive X-ray spectroscopy) allow mapping the positions of different metals and the chemical order can be seen. In addition, the magnetic property can be investigated using electron holography and Lorentz microscopy, where the change in phase information is recorded, which is directly related with the local variation in magnetic induction and the electrostatic potential.


Scanning Transmission Electron Microscopy Electron Energy Loss Spectroscopy Scanning Transmission Electron Microscopy Image Atomic Column Electron Energy Loss Spectroscopy Spectrum 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The author would like to acknowledge Dr. Tanya Prozorov for her support, reading the manuscript, and valuable discussion in preparing this manuscript. This work was supported by the US Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering. The research was performed at the Ames Laboratory, which is operated for the US Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358.


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Authors and Affiliations

  1. 1.Emergent Atomic and Magnetic Structures, Division of Materials Sciences and EngineeringAmes LaboratoryAmesUSA

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