A Comparative Study Of Nd: YAG Laser Wavelength Effect On Gold Nanoparticles: Design, Synthesize And Optical Properties

The development of production techniques for nanomaterials has led to an urgent need to manage the composition and properties of these materials to fit a variety of applications and increase their effectiveness. In this study, the effects of three different laser wavelengths; 266, 532, and 1064 nm on the optical characteristics and the concentrations of gold nanoparticles (AuNPs) generated using the Nd: YAG laser ablation processes are investigated. UV-Visible spectroscopy and FESEM were used to investigate the NPs optical and structure characteristics. In UV-Visible measurements, the absorption peaks for 266, 532, and 1064 nm were 533, 497.6, and 229.7 nm, respectively. Indicating that higher wavelengths have an effect on the number and size of AuNPs. The corresponding direct energy gap (Eg_d) for AuNPs were 4.95, 2.46, and 1.99 eV at 266, 532, and 1064 nm, while the indirect energy gap (Eg_in) was 3.73, 1.48 and 1.54 eV, respectively. The Urbach energies of these samples are 0.599, 4.545, and 4.484 eV. Finally, the results of size, concentration and other statistical measurements were computed based on FSEM of these samples. Our findings were compared to prior studies that used different preparation methods. As a result, the wavelength is an important parameter for synthesis, studying, and controlling the behavior of AuNPs, facilitating their development in a variety of applications such as nano-medicine, sensors, and optical switching.