Platinum nanoparticles were prepared by reducing H2PtCl6 dissolved in water with the help of hydrogen plasma generated right above the aqueous solution, thus the small surface area of the solution contacting the plasma becomes the active reaction zone. This simple method to fabricate the nanoparticles did not necessitate use of reducing agents and polymer protective materials. The average particle size was around 2 nm with the solution temperature set at 10 °C.
