Patent attributes
Provided is a method of making colloidal platinum nanoparticles. The method includes three consecutive steps: dissolving platinum powders by a halogen-containing oxidizing agent in HCl to obtain an inorganic platinum solution containing an inorganic platinum compound; adding a reducing agent into the same reaction vessel to form a mixture solution and heating the mixture solution to undergo a reduction reaction and produce a composition containing platinum nanoparticles, residues and a gas, and guiding the gas out of the reaction vessel, wherein the amount of the residues is less than 15% by volume of the mixture solution; and adding a medium into the same reaction vessel to disperse the platinum nanoparticles to obtain colloidal platinum nanoparticles. The method is simple, safe, time-effective, cost-effective, and has the advantage of high yield.