激光蒸凝法工艺参数对Zn／ZnO纳米粒子性能的影响及临界粒子半径r＊的研究

Influence of Laser Heating Gas-evaporation Synthesis Parameters on the Properties of Zn/ZnO Nanoparticles and Study on the'r*

采用激光蒸凝法 ,以 1 50WCWCO2 激光器为光源 ,金属Zn为靶材 ,成功地制备出了Zn和ZnO纳米粒子。较详细地研究了实验参数对纳米粒子性能的影响 ,并应用经典成核理论对粒子的形成过程进行了研究。实验结果表明 ,制备工艺条件对形成的纳米粒子有一定的影响 ,反应压力和载气流量影响纳米粒子的形貌。不同的反应气氛制备的产物不同 ,在惰性气氛下产品纳米粒子是Zn和ZnO的混合物 ,在氧气气氛下 ,所得的纳米粒子是纯ZnO ;在氢气气氛中得到较纯的Zn纳米粒子。通过对临界粒子半径r 的回归分析 ,说明Zn纳米粒子的粒径主要由反应压力控制 。

Zn/ZnO nanoparticles were prepared by Laser heating gas-evaporation method in this paper, with a 150W CW CO 2 laser as light source and Zinc as a target. The effects of synthesis parameters on nanoparticles was studied in details, and the nanoparticle's formation process was also studied by using the classic nucleation theory. The experimental results show that the process parameters such as reaction pressure, the sort and rate of airflow affect the sizes and crystal system of nanoparticles. The products are varied with reaction atmospheres. It is also discovered that Zn/ZnO nanoparticles are found in inert gases. While pure acicular ZnO nanoparticles are acquired in the oxygen, and Zn nanoparticles are obtained in the hydrogen. Through the regression analysis of critical radius ,it is show that Zn nanoparticles' diameters are determined by reaction pressure and irrelated to the rate of airflow.