Laser ablative nanostmcturing of Au in liquid ambience in continuous wave illumination regime

摘要

We study surface modifications and fabrication of nanoparticles under ablation of water-immerged Au target by a moving beam of continuous wave Ytterbium fiber laser (532, 1064 nm). Our analysis of the target surface reveals the presence of solidified nanoscale Au nanoparticles distributed over the crater of the laser beam, which is consistent with the presence of metal melting and evaporation effects. Optical imaging of the hydrodynamic process shows the presence of convective flows leading to a strong mixing of the liquid medium during the laser ablation process. The laser ablation process results in the production of gold nanoparticle colloids with average particle sizes smaller than 10 nm under relatively narrow size dispersion. Au nanoparticles prepared by CW laser ablation of Au in deionized water are of importance for a variety of applications, including biomedical, catalysis and electrocatalysis, photovoltaics etc.