Fabrication of metal nanoparticles and nanorods/nanowires by a photochemical reaction

A simple approach to the synthesis of Ag, Au, and Pt nanoparticles by a photochemical reaction at room temperature was demonstrated. Metal precursors, sodium citrate as a capping agent, and water were used for the synthesis of metal nanoparticles. By controlling of UV exposure time, the particle size distribution of metal colloidal solution can be possibly tuned. For the growth of Ag nanostructure such as Ag nanorods / nanowires, citrate-capped Pt nanoparticle seeds played a crucial role as a catalyst. Sodium citrate plays a key role for a photochemical reaction to synthesize metal nanoparticles. From the results of UV-vis. spectra, photographs, and particles size distribution of the metal colloidal solutions, we can deduce the size control of metal nanoparticles by controlling of UV exposure time.