Since nano science and technology has been developed at the end of the 20st century, the key technical issues is how to get a large number of high purity nano materials which were precisely controlled on the morphology, size and structure, and improve the dispersion and stability of nano materials. Among the numerous methods, laser as an advanced technology has got more and more attention. And the introduction of liquid medium makes the laser ablation process become more complex. This work presents the characteristics of nano-sized magnetic material. Focus on the application and preparation of NiO nanoparticles. By using liquid phase pulsed laser ablation method, NiO nanoparticles have been made in different liquid media. The comparison of the effect of different liquid medium on composition, size and shape, and process mechanism of the preparation by this method were discussed. In addition, because of the magnetic properties of the NiO nanoparticles obtained, it can be better applied in many fields. This unique method of liquid phase pulsed laser ablation, is expected to obtain new nano structure and material, show better physical and chemical properties of material.

Keywords: Nio, Nano particles, Laser ablation.