Hydrothermal synthesis of platinum group metal nanoparticles

Abstract

A novel route for the synthesis of platinum group metal nanoparticles has been reported. The synthesis is based on the addition of tetramethylammonium hydroxide (TMAH) to the aqueous PtCl 4, IrCl 3 or Rh(NO 3) 3 solution followed by the hydrothermal treatment of these precipitation systems at 160 °C. The mean size of nanoparticles was 9.2 nm for platinum, 21 nm for iridium, and 28 nm for rhodium. The average crystallite size was estimated at 7.4 nm for platinum, 3.1 nm for iridium and 3.5 nm for rhodium. The possible mechanism of platinum group metal nanoparticles formation is briefly discussed.