Eur. Phys. J. D 24, 257-260 (2003)
https://doi.org/10.1140/epjd/e2003-00101-2

Core size effects on electrodeposition of gold nanoparticles attached with biferrocene derivatives

Department of Chemistry, School of Science, The University of Tokyo, Tokyo 113-0033, Japan

Corresponding author: ^a nisihara@chem.s.u-tokyo.ac.jp

Received: 10 September 2002
Published online: 3 July 2003

Abstract

Biferrocene-modified gold nanoparticles (Au_n-BFc) comprising 1.7, 2.2 and 2.9 nm in average core diameter, d, were synthesized by a substitution reaction of octyl thiolate-covered nanoparticles with biferrocene-terminated alkanethiol, 1-(9-thiononyl-1-one)-1',1''-biferrocene (BFcS). All sizes of Au_n-BFc undergo two-step oxidation reactions in 0.1 mol dm^-3 Bu₄NClO₄-CH₂Cl₂ and consecutive potential scans including the second oxidation process lead to the formation of an adhesive redox-active gold nanoparticle film on an electrode. The thickness of the Au_n-BFc film is controllable by the number of potential scans. The scanning tunneling microscope images reveal that the Au_n-BFc (d = 2.9 nm) film forms many domains of the assembled Au_n-BFcs, especially the particles are isotropically assembled in line.