Preparation Of Nano Particles In Laser Ablation In Liquids

When the particle size narrowed down to nanometer scale, characteristics of nanoparticles appear distinct difference from other particles: the surface and interface effect,unique small size effect and quantum size effect. These effects of nanometer particles cancause better sensitivity performance than other conventional particles on the electrical,thermal, magnetic, optical field. Researching on nanoparticles can bring huge economicbenefits and social benefits to people, and nanoparticles have more broad market prospects.In the21th Century, nanoparticles have been widely used in many areas as physics,chemistry, biology, materials, medicine, environment, paper, plastic etc..Preparation technology of nanoparticles can be classified into two categories thechemical method and physical method, chemical method has many shortages such as moreimpurity defect products, quite complex preparation process. Compared with chemicalmethod, physical method is relatively simple. So the technology using laser ablation inliquid (LAL) aroused much concern. In this article, Zinc Oxide and titanium dioxidenanoparticles were prepared by LAL, we also studied the optical properties,structure, sizeand morphology of the nanoparticles, and the mechanism of this technology has beenreported.The main research contents list as followed:1.Characteristics,applications and preparations of nanoparticles are introduced.thesituation of laser ablation of nanoparticles also studied, then summarized the advantagesof laser ablation in liquids.2.Using laser ablation in liquids ZnO nanoparticles has been investigated.In theexperiment the pulsed laser was focused onto the Zn target in the water and the solvent ofPVP. The nanoparticles are prepared with different ablation power. The shape, structureand luminescence of ZnO nanoparticles are researched via PL, XRD and AFM. Therelationship of nanoparticles diameter and laser output energy are researched. By usingpicosecond laser and nanosecond laser in different liquid medium (water and PVP solution)Zinc Oxide nanoparticles were prepared with Zn target. We also study the optical properties and morphology of the prepared nanoparticles by LAL. In addition,pulseenergy seems a useful method for controlling nanoparticles size by laser ablation inliquids.We find that the diameter of nanoparticles decreases with the increase of pulseenergy.3.TiO2nanoparticles prepared by laser ablation in liquids both by picosecond andnanosecond laser were investigated.In the experiment the pulsed laser was focused onto theTi target in the water and the solvent of PVP. The nanoparticles are prepared with differentablation power. The shape, the structure of TiO2nanoparticles are researched via XRD andAFM. The relationship of nanoparticles diameter and laser output energy are researched.