Preparation of Silver Nanoparticles By Nd:YAG Pulsed Laser and Study Their Optical and Structural Properties

In this study, colloidal silver nanoparticles were prepared using the pulsed laser ablation in liquid (PLAL) technique. The research focused on clarifying the effect of the number of laser pulses on the optical properties of nanoparticles derived from high-purity silver targets immersed in 5 ml of distilled deionized water. A Q-switched Nd:YAG laser was employed, with fixed parameters: energy at 260 mJ, wavelength at 532 nm, pulse duration of 10 ns, and frequency of 1 Hz. The number of pulses used for nanoparticle preparation was 100, 200, and 300. The behavior of the visible and ultraviolet absorption spectra of the silver nanoparticles was studied as a function of wavelength and the number of pulses. The results indicated that the absorption intensity increases with the number of pulses, suggesting an increase in the concentration of nanoparticles. Additionally, the conductivity, dielectric constant, and exertion coefficient also increased with the number of pulses. Through the absorption spectrum the optical energy gap was also calculated for AgNPs, It was shown to increase from 2.251eV to 2.549 eV with the number of laser pulses increasing from 100 to 300 pulses. The average diameters of the particles were calculated by SEM examination and were equal to 20.984nm, as well as found through the TEM examination and were equal to 28.1877nm, and these tests showed that the prepared nanoparticles have a spherical shape. Through the results of XRD, the average crystallite size of the same particles was found to be 14.7nm.