Synthesis of ZnO_2 nanoparticles by laser ablation in liquid and their annealing transformation into ZnO nanoparticles

摘要

A pulsed laser emitting UV radiations generated by the third harmonic of Nd:YAG was applied for the synthesis of nano-structured ZnO_2 and ZnO. For the synthesis of nanoparticles of ZnO_2, a high-purity metallic plate of Zn target was fixed at the bottom of a glass cell, in the presence of deionized water mixed with oxidizing agent H_2O_2, under repeated laser irradiation. The optical properties, size and the morphology of the synthesized ZnO_2 and ZnO by laser ablation was influenced strongly by post-annealing conditions which is not previously reported. By annealing ZnO_2 at 200 ℃ for 8 h, the product (ZnO_2) synthesized primarily was converted completely to ZnO. By variation of the annealing temperatures from 200 to 600 ℃, the grain size of ZnO changes from 5 to 19 ran with a change in lattice parameters, the band gap and some other optical properties of nano-ZnO.