X-ray diffraction and transmission electron microscopy measurements of cobalt nanospheres, disks and rods
EMSL Project ID
2513
Abstract
I am a graduate student at the University of Washington Materials Science and Engineering department. I am working in with the Integrated Nanostructures Group. Kannan M. Krishnan is the principal investigator. My research group is involved in the synthesis of cobalt nanoparticles. We can produce spheres with diameters in the range of about 3 nm to tens of nanometers, as well as rods and disks with similar dimensions. The particles are coated in a organic surfactant that is required for stabilization during synthesis. Nanoparticles of pure cobalt can take one of three crystallographic structures, face-centered cubic, hexagonal close-packed or an unstable phase called epsilon. The particles are synthesized in solution, then precipitated to form a powder. We wish to use x-ray diffraction, theta - two theta scans, to determine which of the three phases is present, as well as the relative concentration of each phase. The XRD system available in the materials science department cannot produce an intense enough x-ray source for our purposes. Additionally, we would like to utilize the JEOL 2010 TEM for high resolution imaging. With the proper orientation, disks and rods have the same cross-section, making them difficult to distinguish. The JEOL should provide sufficient resolution to conclusively characterize the shape of the particles. More importantly, once we have determined the shape of the nanocrystals, we can then determine which crystallographic plane is normal to the growth axis. Lastly, I would like to use nanobeam diffraction to obtain the crystal structure of individual particles. I can then compare the electron diffraction data to the x-ray diffraction data. Thank you for considering this. P.S. I will select the independent option below, however if there is anyone who is interested in collaborating on this project at EMSL then please let me know.
Project Details
Project type
Exploratory Research
Start Date
2002-05-14
End Date
2004-05-21
Status
Closed
Released Data Link
Team
Principal Investigator