Fullerene modification of gold electrodes and gold nanoparticles based on application of aromatic thioacetate-functionalized C60

Abstract

A new procedure for the synthesis of S-acetyl-derivatized fullerene is described. The deprotected aromatic S-acetyl-derivatized fullerene was employed for efficient modification of a gold electrode and gold nanoparticles. The proposed deposition procedure of fullerene derivative on Au surfaces allows the control of the thickness of the self-assembled fullerene layer. The modified surfaces were characterized by electrochemical methods and X-ray photoelectron spectroscopy (XPS). Functionalized fullerenes largely retain favorable redox electronic properties, behaving as an electron sink and revealing 4 reversible sequential 1e electrode processes at slightly more negative potentials than those observed for unsubstituted C₆₀. For the first time, fullerene-capped gold nanoparticles were obtained by a two-step ligand exchange procedure involving substitution of alkanethiol with thiolated fullerene derivative following the synthesis of alkanethiol capped nanoparticles. The ligand exchange procedure was very efficient – the number of fullerene moieties per single gold nanoparticle was found to be as high as 30.