Electronic Properties of Wires Fabricated via Dielectrophoresis of Colloidal Gold Nanoparticles

Abstract

Gold nanoparticles were fabricated via the precipitation of gold that follows the reduction of tetrachloroauric acid in the presence of a ligand such as citric acid. Synthesis and stabilization of gold nanoparticles has been achieved in a variety of solution environments whose character ranges from polar (water) to non-polar such as dodecane. The size of the nanoparticles was measured through Mie theory analysis of extinction of UV-visible spectra and transmission electron microscope (TEM) images of particles dried onto a TEM grid. Successful mechanical ‘break-junction’ experiments in air and in the colloidal solutions demonstrate that the lowdimensional transport character observed in such experiments is not significantly affected by the solution/environment. Evidence has been obtained that, at and near the time of formation, the dielectrophoretically-grown wires formed within these colloidal suspensions have similar electrical transport characteristics to those found in mechanical break junctions.