Fabrication and electronic properties of gold nanoparticle superlattices

Well-defined planar 1D chains and 2D superlattices of gold (Au) nanoparticles in the 1.5similar to9.7 nm range were successfully fabricated by a self-assembly technique. When the nanoscale ridge-and-valley structured carbon substrates were dipped in toluene solution of 3.4-nm Au nanoparticles followed by a natural dry, a planar array of 1D chains of Au nanoparticles were formed at the valleys of carbon substrates. On the other hand, the 1.5similar to9.7-nm Au nanoparticles protected by alkanethiols or 2,6-bis(1'-n-thioalkyl)benzimidazol-2-yl)pyridine easily formed hexagonal 2D superlattices on the flat carbon substrates, the inter-particle spacing being tuned by the ligand length and so on. It was found that for 2D superlattices consisting of large particles of similar to5 nm the electron behavior was dominated by the Coulomb blockade effect at low temperature while the I-V response was ohmic at room temperature. (C) 2003 Published by Editions scientitiques et medicales Elsevier SAS on behalf of Academie des sciences.