Formation of Mg and MgO Nanocrystals by Laser Ablation in Liquid: Effects of Laser Sources

In this paper, two kinds of pulsed laser sources, an acousto-optically Q-Switched Nd:YAG laser, and a copper vapor laser (CVL) were used separately to vaporize the Mg metal target in isopropanol liquid medium. The compositions and structures of synthesized material were investigated by FTIR spectrum, X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM). Formation of Mg and MgO nanocrystals by both kinds of lasers was recognized by XRD analysis and the obtained results from different lasers were compared and discussed. Electron microscopy observations revealed that morphology of the synthesized nanocrystals are quite different. The structures obtained using CVL are cubic in shape with about 1 jam lengths. Ablation process using Nd:YAG laser leads to structures which comprised of spherical, and platelet-like crystals. Sizes of the formed nanostructures in this case are in the range of 80-120 nm. The different results were attributed to the intrinsic difference of operating parameters of two employed lasers.