The effects of different parameters and interaction angles of a 532 nm pulsed Nd: YAG laser on the properties of laser-ablated silver nanoparticles

Laser ablation in liquids (LAL) is being used to create contaminant-free colloidal nanoparticles with unique properties. The absorbance of a substance to incident laser light, which results in the formation of a nanoparticle, as well as the control of size and shape, are all affected by many factors. Among these are laser energy, laser wavelength, ablation time, laser polarization, angle of incidence, and material properties. In this paper, we present the results of producing silver nanoparticles' colloids in distilled water by laser ablation from a bulk silver metal using the 2nd harmonic of Nd: YAG laser. The effects on the nanoparticles due to different ablation times, energies, and laser incidence angles have been studied. The particle size, morphology, and absorption spectrum of the nanoparticles colloids are derived from the transmission electron microscopy (TEM) and ultraviolet-visible (UV-Vis) spectrophotometer. The silver nanoparticles TEM image shows a spherical-like shape at different ablation time, different energies, while showing different nano shapes at ablation laser pulse energy >= 100 mJ, and when the angle between the laser beam and the silver bulk was changed from 90 degrees to 60 degrees. The size distribution of the nanoparticles was found to be shifted to the quantum size range (<10 nm) with increase of the laser ablation time and reach an average size of 7.5 nm at 30 min ablation time with laser pulse energy at 100 mJ. Also, in the case of 30 min ablation time and laser pulse energy of 100 mJ, the obtained nanoparticles have a size distribution falling into two ranges of 1-10 nm (55%) and 10-20 nm (45%).