Synthesis, Self-Assembly, and Transformations of Metal and Magnetic Nanoparticles
Joseph B. Tracy, Ph.D.
Department of Materials Science and Engineering, North Carolina State University
Abstract: Ligand-stabilized nanoparticles have size- and shape-tunable physical properties, and the ligand monolayers facilitate self-assembly. New approaches for synthesizing, assembling, and transforming nanoparticles are needed to obtain nanomaterials with novel properties: (1) New methods have been developed for the large-scale synthesis of Au nanorods and for synthesizing AuAg and CoNi nanoparticles. (2) Magnetic field-directed self-assembly of magnetic nanoparticles enables the synthesis of polymer composites containing embedded nanoparticle chains. (3) Electrospinning of aligned polymer nano/microfibers from a Au nanorod/polymer solution yields macroscale alignment of the nanorods, thereby enabling studies of their anisotropic optical properties. (4) Nanostructural transformations accompanying the conversion of Ni nanoparticles into NiO and NixPy are of interest for fabricating heterostructured nanomaterials. (5) Deposition of thin Al2O3 layers onto monolayers of FePt nanoparticles enables their sinter-free conversion from an alloy phase into intermetallics for magnetic recording and catalysis.
Biography: Joe Tracy is an Assistant Professor in the Department of Materials Science and Engineering at North Carolina State University. He completed his undergraduate studies in Chemistry at the University of California, Santa Barbara, in 2000. He received his Ph.D. in Physical Chemistry from MIT in 2005 and conducted postdoctoral research at the University of North Carolina, Chapel Hill. He joined NC State in 2007, where his primary interests include the synthesis, self-assembly, and transformations of metal and magnetic nanoparticles. In 2011, he received an NSF CAREER award.