AVS 53rd International Symposium
    Nanometer-scale Science and Technology Monday Sessions
       Session NS-MoA

Paper NS-MoA4
Morphology Control of Ferromagnetic Core-Shell Nanoparticles Electrodeposited on H-terminated Si(100)

Monday, November 13, 2006, 3:00 pm, Room 2016

Session: Nanoscale Structures and Characterization I
Presenter: K.T. Leung, University of Waterloo, Canada
Authors: L.Y. Zhao, University of Waterloo, Canada
N. Panjwani, University of Waterloo, Canada
T. Chan, University of Waterloo, Canada
N. Heinig, University of Waterloo, Canada
K.T. Leung, University of Waterloo, Canada
Correspondent: Click to Email
Our recent work on metal nanoparticles (Cu, Ni, Co) electrochemically deposited on an ultrathin polypyrrole film grown on a gold-coated silicon electrode shows that the morphology (size, shape, density and distribution) of these nanostructured materials can be easily controlled by varying the wet deposition conditions (pH, electrolyte concentration, deposition potential, charge, and current density), and the thickness and morphology of the polypyrrole film. Using similar electrochemical techniques and by manipulating the solution chemistry, we have recently obtained on a H-terminated Si(100) surface mono-sized, uniformly distributed Fe core-shell nanoparticles with several different morphologies: quantum dots of 4-10 nm in diameter, 30x120 nm "nano-rice", and 40-60 nm nanocubes. These nanoparticles are found to consist primarily of a polycrystalline Fe metallic core and a mixed Fe oxides shell (of several nm thick) and all exhibit interesting magnetic properties. In the present work, we illustrate that morphological changes can be induced by controlling the substrate conditions, solution parameters and an external magnetic field.