Synthesis of platinum nanoparticles by aerosol assisted deposition method

Abstract

An atmospheric pressure aerosol assisted deposition method has been developed to grow highly oriented nanoparticles and thin continuous films of platinum on a variety of substrates for applications such as catalysts including their use in proton exchange membrane fuel cells. Pt nanoparticles with sizes ranging from 4 nm to 78 nm were synthesized on Si, silicon dioxide coated Si substrates and carbon nanotubes. The size and density of the nanoparticles was found to depend strongly on the precursor carrier gas flow rate and deposition time. The particles showed preferential orientation of (111) that was independent of substrate used. The resulting nanoparticles were characterized by Scanning Electron Microscopy, X-ray Diffraction Spectroscopy and X-ray Photoelectron Spectroscopy in order to obtain information about their morphology, crystallinity and composition. The method developed can deposit uniform coatings of highly oriented, pure Pt nanoparticles without the need of any substrate pretreatment such as surface functionalization, deposition of seed layer for electrodeposition on insulating or semiconducting substrates, and without the use of expensive vacuum equipment.