An improved Brust's procedure for preparing alkylamine stabilized Pt, Ru nanoparticles

Abstract

An improved method to prepare alkylamine-stabilized Pt and Ru nanoparticles based on the original Brust's procedure [J. Chem. Soc., Chem. Commun. (1994) 801] has been developed. The new method involves, firstly, mixing an aqueous solution of metal salts such as PtCl6 2-, PtCl 4 2- or Ru3+ with an ethanol solution of dodecylamine; extracting the metal ions into a toluene layer; and finally reducing the metal ions to their zero valent states using NaBH4. Alkylamine-stabilized Pt nanoparticles prepared this way had a polyhedral or wormlike appearance, depending closely on the chemical nature of the metal precursor salts being used. On the contrary, dodecylamine-stabilized ruthenium nanoparticles were predominantly spherical. The particle formation and growth processes in the hydrocarbon layer could be influenced by the different ways dodecylamine was bound to H2PtCl6, K2PtCl 4 or RuCl3 at the precursor stage. © 2004 Elsevier B.V. All rights reserved.