Magnetophoretic deposition of nanocomposites

This communication reports the novel idea of using a magnetic field gradien t to hold magnetic nanoparticles at desired densities in a fixed location ( e.g., on an electrode surface), while metal atoms are deposited electrochem ically in the interstices between them. Using it, nanocomposites consisting of gamma-Fe2O3 nanoparticles (with a mean size of about 40 nm) in a copper metal matrix were reproducibly fabricated, with particle volume fractions ranging from 0.2% to 50%. These nanocomposites, ceramic magnetic particles in a conductive metal matrix, are expected to have unusual or enhanced mech anical, electrical, and magnetic properties.