Optical properties of synthesis nano silver using laser ablation in liquid

In this research, silver nano particles were prepared using pulsed laser ablation method in liquid, using silver metal. One of the first signs of the production of nano particles is the change in the color of the solution, which is an initial indicator of the generation of these particles. 5 ml of de ionized distilled water was used to prepare samples with different pulse numbers (300, 600, 900). It was observed that the color of the distilled water gradually changed to a dark color with increasing the number of pulses, confirming the production of silver nano particles. The spectral absorption of the prepared solutions was measured using a UV-Vis device, where the results showed that the absorption peaks were located at a wavelength of 400 nm, which is additional evidence of the formation of silver nano particles. The energy gap was also calculated, which had values of (3.15, 3.08, 3.04) eV, respectively. XRD analyses showed the formation of the cubic crystal structure of AgO/Ag particles. Spherical and sub-spherical crystals were detected by scanning electron microscopy (FESEM) images, and atomic scanning electron microscopy (AFM) showed the surface topography, where it was observed that the grain diameter increased with increasing number of pulses and was in the range of (24.23, 64.55, 37.92) nm.