A Simple LargeScale Synthesis of Nearly Monodisperse Gold Nanoparticles with Surfactants.pdfVIP

VOLUME 16, NUMBER 13 JUNE 29, 2004 © Copyright 2004 by the American Chemical Society Communications A Simple Large-Scale Synthesis of Nearly be surface derivatizable with hydrophobic and hydro- Monodisperse Gold and Silver philic surfactants. In the past, such nanoparticles were Nanoparticles with Adjustable Sizes and synthesized by either one of two methods, the citrate with Exchangeable Surfactants method introduced in 1857 by Faraday,12 and later refined by Frens,13 and the two-phase method originally Hiroki Hiramatsu and Frank E. Osterloh* described by Wilcoxon et al.14 and later modified by Brust et al.15 The citrate method produces nearly Department of Chemistry, monodisperse gold nanoparticles in the size range from University of California at Davis, 2 to 100 nm.1 Problems of the citrate method are a low Davis, California 95616 gold nanoparticle content of the resulting solutions (0.01 M) and the restriction to water as a solvent. Received March 18, 2004 Because the charge-stabilized particles easily undergo Revised Manuscript Received April 26, 2004 irreversible aggregation upon addition of elect