Synthesis of Pt Nanoparticles in Oil-in-Water Microemulsions: Phase Behavior and Effect of Formulation Parameters on Nanoparticle Characteristics

Abstract

Pt nanoparticles were synthesized in oil-in-water (o/w) microemulsions, in contrast to the typically used water-in-oil microemulsion method. The new strategy implies the use of a Pt organometallic precursor (1,5-cyclooctadiene dimethyl platinum (II)), dissolved in nanometre-scale oil droplets, stabilized by surfactant, and dispersed in a continuous aqueous phase. Three different nonionic microemulsion systems were used. Characterization studies demonstrate that small, nanocrystalline Pt nanoparticles were obtained. The particle size and agglomeration was dependant on the microemulsion system used and its composition. The obtained results demonstrate the feasibility of this approach for the controlled synthesis of Pt nanoparticles with potential for catalytic purposes.