Generation of metal nanoparticles by laser ablation

Abstract

The process of nanoparticle generation during nanosecond and picosecond laser ablation of various metals (Ni, Al, W, and stainless steel) in ambient air and argon gas was investigated. The number concentration of nanoparticles generated by laser ablation in argon gas was up to 100 times higher compared to that in ambient air. Three stable separate size peaks of nucleation, Aitken, and accumulation modes of nanoparticles were observed in case of argon gas, while in ambient air particles of a wide size spectrum (8-200 nm) were generated. The natural precursors in ambient air can have an effect on the size spectrum of particles composed of various chemical compounds with target material during the ablation process. The influence of laser process parameters and properties of investigated metals on the number concentration and size distribution of nanoparticles generated during ns- and ps-laser ablation was observed. © Lithuanian Academy of Sciences, 2011.