PREPARATION OF NANOPARTICLES BY LASER ABLATION AT DIFFERENT WAVELENGTHS

Abstract

Through laser ablation in liquid, with a Q-switch Nd:YAG laser operating at different laser energy and wavelengths, a TiO2 NPs suspension in deionized distilled water was produced. Characterization of the materials was done using transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-visible absorption spectra obtained with a UV-visible spectrophotometer. The UV-Vis spectra, on the other hand, revealed the distinctive absorbance peak of TiO2 NPs across bands. TiO2NPs' estimated optical band gaps were 3.26 eV, 3.3 eV, and 3.09 eV at (250 mJ, 300 mJ) at wavelengths of 1064 nm and 532 nm, respectively. TEM pictures displayed a spherical-like form of titanium NPs with varying size distributions vary based on the different wavelengths utilized. The TiO2 NP size distribution and laser wavelength were also shown to be related, with a smaller size distribution being associated with a lower wavelength. An X-ray diffraction examination revealed that the TiO2 NP's structure is polycrystalline and has several peaks.